# Cooper F-Gauge Locomotive Build



## Grimm (Oct 5, 2009)

I thought that It would be better to start a new thread instead of using the old one. That way it separates the research from the locomotive build. This will be my first foray into live steam building and I'm very excited about it. I bought Peter Jones' book "Building Small Steam Locomotives" to help me along. If I start doing something stupid, please let me know and I will try to let you know what I'm about to do before I attempt it. Thanks everyone for all the help so far, I'm really looking forward to this.









To start with I need some wheels with spokes, at least that appears to be what they preferred to use in 1830. I wasn't able to find much of anything here in the US. So I looked to our friends across the pond to see what they have. Spoked wheels were used much later then in the US and the English railroads didn't change their wheels as much. I was able to find an almost perfect match from the Walsall Model Industries company. Their G1833 cast iron wheel were just the right size, although maybe a little small, and had the right number of spokes. Here is a picture of the cast iron wheels Lez Allen sent me (shipping was FAST, only 7 days to get all the way here to Alaska!!):











If my math is correct the wheels, which are 30" in diameter prototypically, would be about 37.5mm in diameter. The wheels I purchased from Walsall are about 38.2mm in diameter, so not much fudge room. I hope that they are not too small. The only other thing that might be a problem is that the area between the spokes was not cast very deep, I would have to remove a lot of material from the back of the wheels to expose the spokes. I'm thinking that I might just drill a hole between each spoke and then file the rest of the web out. It might work out actually for the best because on these early wheels the hub would stick out from the back of the wheel, instead of the front. There is a lot of extra metal on the back to accomplish this. Does this sound like a good plan? Thanks,


Jason


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## abby (Jan 9, 2008)

Hi Grimm , sand cast wheels of small size are more successfully moulded by having a "button" on the back , otherwise the spokes are often faulty , the idea is that the back of the wheel is machined away until the correct spoke depth is achieved. 
By doing this there is no need to drill or file away the button as it is surplus and removed in the machining, you may find a few tips on building your first live steam loco on the forum at www.unionsteam.co.uk.


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## Grimm (Oct 5, 2009)

Thanks Abby, that make a lot of sense. The button probably helps to strengthen the spokes so they don't break when you are machining the wheel as well.


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## JPCaputo (Jul 26, 2009)

The "button" is part of a trick used in casting. It may either be a sprue as a multi-part pour. Or it is for expansion contraction of the metal so that as the part cools down and shrinks there is metal available to pull from. Without this feature, provided by the sprue or for the extra metal in the pour, there can be air-bubbles that accumulate on the top surface.


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## xo18thfa (Jan 2, 2008)

Jason: Get in touch with Howard Maculsay, his handle is "maculsay" here on MLS. He used cast iron pilot wheels like these on his Model "T" rail bus and they turned out great.


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## Kovacjr (Jan 2, 2008)

I think the issue you have with the Spoke depth is that thgese wheels are porobally 1/32 as most of the casters Ive come across only have standard gauge wheels. Not an Issue just the width of the wheel should be machined to 1/32 measurements if needed to reveal the spokes.


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## Grimm (Oct 5, 2009)

Thanks JP 

Thanks Bob, I will do that. I did try to start to machine the wheels, but the only tool bits I have are made from HSS. Soooo, you can guess that I didn't get very far. I'm lucky in that I work in the same building where the university's machine shop is. I talked to them about it and I have now ordered some carbide tipped tool bits. I'm waiting for them to arrive and then I can start on finishing the wheels.  

Jason - Thanks, that makes a lot of sense. Although I will be machining them to F-scale standards (1/20.32) so it looks like I will be drilling holes and filing the spokes out. It's not a problem, just a bit more work. I guess having the button is a good thing after all, given that I will most likely need the extra metal. 

Jason


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## Steve Shyvers (Jan 2, 2008)

Jason,

A while back I turned a couple of Walsall castings on my little Taig lathe using an HSS cutting tool. I didn't know any better, and at the time carbide bits seemed too exotic to be obtainable by a miserable livesteam apprentice like me. Cutting through the "skin" on the casting caused the Taig to complain a bit, but after that the cast iron cut like butter. (Harry Wade once used that expression to describe working with cast iron, unless it's got hard spots in it.) Cast iron can be such a joy to work on a lathe that the danger is cutting off too much!

The Walsall castings were for 10-spoke 1.48" diameter pilot wheels (Walsall # W26, I believe), and I wanted to use them on a 1:20 chain-driven loco. I knew nothing about wheel standards so measured several commercially available wheels to come up with what I thought was a reasonable wheel profile. When I got through the rim OD came out to be 36mm, and its width from face to back of flange was about 6.5mm. The flange width was 1.5mm, which made the tread width 4mm.

Like you, I thought that I'd have to live with the "button" blanking off the areas between the spokes, but was advised that standard practice was to turn off the metal on the back of the wheel to expose the spokes. I did as told, but instead of turning off the whole diameter I turned off only the portion that blanked off the spokes, which allowed the wheel to retain a nice thick rim and a small boss on the back of the hub.

I did not keep notes on the turning process, but I seem to recall that I probably did about ten times as many lathe operations per wheel than an experienced builder would do. I was just happy that the two wheels came out to be the same diameter and profile. I did make a mandrel that mounted in the 4-jaw, however, to hold the wheels while turning so they didn't have to be chucked and centered each time. If you'd like I could try to dig out the mandrel and shoot a photo of it.

If I remember halfway correctly, the sequence of operations probably went like this:

1. Chuck and roughly center each wheel in the 4-jaw with the jaws gripping the OD of the tread. 

2. Face off the back of the wheel to provide a smooth reference surface. The part of the button that covers the spokes could be removed at this time. I think that's what I did, because the mandrel I made had a small post that fit between the wheel spokes to act as a lathe dog and keep the wheel from turning on the mandrel.

3. Turn the OD of the button to round to provide a reference that's concentric with the wheel rim.

4. Flip the wheel around in the 4-jaw, grip it by the OD of the button, and center it carefully.

5. Face off the rim.

6. Face off the hub.

7. Center drill and bore the hub for the axle.

Hopefully at this point the wheel has front and back parallel, and the rim, hub, and axle bore are all concentric. The remaining operations are best done with the wheel on the mandrel, so you can take the wheel on and off to look at it, measure it, head scratch, etc.

Steve


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 17 Dec 2009 07:21 PM 
Thanks JP 

Thanks Bob, I will do that. I did try to start to machine the wheels, but the only tool bits I have are made from HSS. Soooo, you can guess that I didn't get very far. I'm lucky in that I work in the same building where the university's machine shop is. I talked to them about it and I have now ordered some carbide tipped tool bits. I'm waiting for them to arrive and then I can start on finishing the wheels.  

Jason - Thanks, that makes a lot of sense. Although I will be machining them to F-scale standards (1/20.32) so it looks like I will be drilling holes and filing the spokes out. It's not a problem, just a bit more work. I guess having the button is a good thing after all, given that I will most likely need the extra metal. 

Jason 



Jason: HSS tools work on cast iron. Run the lathe as slow as possible and feed the cut slowly too. Use a rather pointed cutter. The trick is getting under the skin of the casting into the base metal. Steve laid out the process, now just run the lathe slow. In the photo there appears to be a sprue bump where they cut off the casting. Grind that sprue off with a bench grinder first. 

The carbide tool will help get under the skin, but run it slow too. It is the skin that is hard on HSS. Once you get into the base metal, it will cut like butter.


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## Grimm (Oct 5, 2009)

Thanks guys, I have five of them now faced off, front and back. Although the sixth one is giving me more problems. I did have to re-sharpen my tool bit after every wheel, so it's probably something I'm doing wrong. Some times, like you said, it would cut like butter. But then the next wheel would just eat the tool bit no matter how slow I would run it. I even ground the outside edge of the button and rim to try and remove some of the hard skin, but it doesn't always work. I will keep trying and if worst comes to worst, the carbide bits should be here next week.  

Jason


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 18 Dec 2009 07:24 PM 
Thanks guys, I have five of them now faced off, front and back. Although the sixth one is giving me more problems. I did have to re-sharpen my tool bit after every wheel, so it's probably something I'm doing wrong. Some times, like you said, it would cut like butter. But then the next wheel would just eat the tool bit no matter how slow I would run it. I even ground the outside edge of the button and rim to try and remove some of the hard skin, but it doesn't always work. I will keep trying and if worst comes to worst, the carbide bits should be here next week.  

Jason 



Is it a hard spot on the casting? A particular place that is difficult to cut? Sometimes iron castings get what they call "chill spots" It's when the casting cools too fast and leaves a very hard spot. If you can't work thru it, you may have to contact the vendor and ask for a replacement. Hopefully you can thru it or the carbides will get it.


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## Steve Shyvers (Jan 2, 2008)

Jason, 

You've probably figured this out by now, but the first cut has to be deep to get under the casting's skin. Otherwise the tool bit just scrapes along the surface. Is this what's happening? If it just scrapes along the surface the tool bit will be ground dull without cutting anything. Also make sure that the tool bit is at the correct height relative to the wheel casting. Too high or too low and the tool bit suffers and won't cut very well at all. You might be dulling the bit and then it's trying to grind through the casting's skin instead of cutting through it. 

When you get the carbide tool bits check with the university machine shop for advice on cutting speed. I've read that carbide tool bits work better at higher turning speeds than would be used for HSS bits. I read that it has to do with carbide edges not being as fine as good HSS edges are, and the carbide needs the brute force of a higher cutting speed to do its job, which is to remove a lot of material quickly, which it can handle. 

All that said, my Taig's slowest speed is 575 rpm. I said before that the Taig complained when I made those first cuts into the wheel castings. Don't recall sharpening the HSS tool bit afterward, but undoubtedly I did. 

Steve


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## Grimm (Oct 5, 2009)

I have 6 of them machined down to almost the correct width now.  The last two are the problem children. I was able to plunge cut towards the center and then cut out to the edge of the button. On these the cast iron must be chilled on the edge of the button, which makes sense. The hard area is about 1/8 inch wide on one and about 1/16th inch on the other. I'm just going to try and plunge cut on the inside of the hard area until I cut it off of the wheels, if that sounds like a good idea? 

Here they are so far:


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## Steve Shyvers (Jan 2, 2008)

Jason. 

Those wheels look nice! If you do a plunge cut inside the hard area will you possibly take off too much material and make the diameter too small? (Especially on the one with the 1/8" wide hard area.) Judging from the other wheels it will probably be okay. On the final wheel you won't want the flange more than 1.5 to 2 mm deep. Alternatively you could wait for the carbide tool bits and see how they handle the hard area. 

Steve


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## Grimm (Oct 5, 2009)

Thanks Steve, I think I will wait for the carbide bits because I just want to see if they can cut this stuff. According to USPS they are in Anchorage, so I should get them Monday. If worst comes to worst, I can always throw the wheel into my wood stove and let it sit over night to anneal. 

Jason


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## Grimm (Oct 5, 2009)

I did have another question, what would be a good way to chuck the wheel up to drill the center hole? I don't have a 4-jaw chuck, just a 3-jaw one. Do you just trust the casting to be good enough and chuck the wheel up? To experiment I chucked on of the wheels up in and ran the dead center into the wheel to see how centered it was. It was pretty close, and I guess it doesn't much matter because you finish the tire on the mandrel. Peter Jones didn't go into much detail in his book on this point, so I'm assuming it's no big deal. It would be nice to get some confirmation though.









Jason


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## Steve Shyvers (Jan 2, 2008)

Jason,

Good question. I hope Bob chimes in too and gives his opinion. Have you measured the total indicated runout (TIR) on your 3-jaw? A typical imported chuck will be .003" or less. There could be variablity depending on chuck source, age, and usage. At 0.003" TIR the chuck is holding the work off center by half that amount, or 0.0015". That's probably acceptable for drilling the axle holes on wheels that will get final turned on a mandrel. The OD of the hubs and the ID of the rims might show a little eccentricity, but probably not overly noticeable on small wheels tucked underneath a small loco. If you wanted to you could always touch up the outer part of the hub OD and rim ID while the wheel is on the mandrel.

Steve


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## Grimm (Oct 5, 2009)

Thanks Steve,

I checked my chuck, at least I think I did. I set up my gauge so that it touched the chuck in the space between the adjustment lug and the jaws. I turned the chuck and it barely moved the needle ( < .001 inches ). It's a new lathe, just bought it in October so it should be fairly straight I hope. Or should I have measured the jaws instead? I did chuck up one of the wheels and turned the lathe on and watched the wheel to see if I could see any eccentricity. Interestingly the OD of the rim and the hub looked pretty stable. The ID of the rim on the other hand did move a lot, which I guess is OK right? 


Jason


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## xo18thfa (Jan 2, 2008)

You can chuck it up in a three jaw and center it by adding shims under one or two of the jaws. It is a very slow, trial and error process, but it works. Use some thin brass strip if you have to bridge a lot, or folded up masking tape works fine for little gaps. Center the wheel on the inside of the rim, not the hub. The inside of the rim is much more visible as it turns, than the hub. Be sure the back of the rim if flat to the chuck.


Steve mentioned total run out. That's how far out the 3 jaw is from perfect centering. You will eventually have to determine that for your chuck if you ever want to center round or hex bar in it. You will need to know how much shim you need and under which jaw. Do you have a dial indicator?? If not, you should get one. And a 4 jaw chuck. You actually need the 4 jaw more than the 3.

Bob


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## xo18thfa (Jan 2, 2008)

BTW, looks like a very nice start on the wheels.


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## Grimm (Oct 5, 2009)

Thanks Bob, 

I see now, I needed to put a bar in the chuck and test it from that, right? I do have a dial indicator that is what I used to test the chuck in my previous message. I hadn't thought about shimming the wheel in the chuck, that makes a lot of sense. 

Jason


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## Grimm (Oct 5, 2009)

I went ahead and cut off a 3.5 inch section of a 3/8" tool steel ground rod to test the lathe chuck runout. When I tested it with my dial indicator it was pretty much the same as before, the needle wiggled about .0005 inches. Is that good? 

Jason


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 21 Dec 2009 02:56 AM 
I went ahead and cut off a 3.5 inch section of a 3/8" tool steel ground rod to test the lathe chuck runout. When I tested it with my dial indicator it was pretty much the same as before, the needle wiggled about .0005 inches. Is that good? 

Jason 
That is excellent. They don't get better than that.


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## xo18thfa (Jan 2, 2008)

What kind of lathe do you have? Check out Little Machine Shop, they have a lot of stuff for hobby sized lathes. They most like would have a 4 jaw that would fit yours.

http://www.littlemachineshop.com/default.php


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## Grimm (Oct 5, 2009)

Thanks Bob,

I have a Grizzly 7X12 mini lathe. I received the carbide bits today and tried them out on the wheel. It worked, the lathe complained all the way but I was able to remove the outer edge of the button.







I also chipped the carbide bit in the process. Then I discovered that the tire rim was also chilled.







I'm just going to anneal the wheel and save myself a lot of grief. I will never be able to profile the tire and the flange with them being so hard. 


Jason


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 21 Dec 2009 03:08 PM 
Thanks Bob,

I have a Grizzly 7X12 mini lathe. I received the carbide bits today and tried them out on the wheel. It worked, the lathe complained all the way but I was able to remove the outer edge of the button.







I also chipped the carbide bit in the process. Then I discovered that the tire rim was also chilled.







I'm just going to anneal the wheel and save myself a lot of grief. I will never be able to profile the tire and the flange with them being so hard. 


Jason 


That's a drag about about the chill spot. Call the vendor and see if you can a replacement casting.

Little Machine Shop has lots of stuff for 7 x 12


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## Grimm (Oct 5, 2009)

It's no problem now, I threw the wheel in my wood stove and let it sit until the fire died and retrieved it in the morning. The wheel still has some small chill spots but nothing I can't work with. I have finished one, that is ONE wheel so far.




























I definitely have a much better appreciation of the work that goes into these little engines. I'm not discouraged though, I still glad I went this route because I will be able to build what I want, and not have to depend on what is popular or available.







Now that I have done one, the rest are in the pipeline to be finished. I did have to file out the webs between the spokes. It's a bit of a pain, but I think it's worth it. I would have had to remove about 2 mm of metal from the back of each wheel. I felt that would be too much, but I did remove about .75 mm to help in the removal of the webs as you can see in the second picture. Jason K. had the right of it when he said that these are probably designed for 1:32 scale and I'm following the 1:20.32 standards so the wheels are thicker then they would be normally. After the wheels it's on to the axles.









Jason


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## abby (Jan 9, 2008)

Jason, nice photographs , I notice two thin lines across the rim of the finished wheel , are these cracks ?


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## Grimm (Oct 5, 2009)

Thanks Abby, 

No, not cracks, scratches from the file. I tried to be careful, but it's inevitable I think.  

Jason


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## xo18thfa (Jan 2, 2008)

Good news Jason. Putting them in the fire is an innovative idea. In annealing like that it is the slow cool down that does the trick. Now that you cracked the code n the wheels, the rest of the engine can proceed. There should be no other cast iron to deal with. Guess you need some scary moments like this from time to time.


Bob


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## Grimm (Oct 5, 2009)

Hi Bob, thanks. That is the truth isn't it.







I have finished all of the wheels. Whew! I think I may have made the flanges short, hopefully not too short.







I also cast up the journal boxes that are based off of the early version of Winan's friction wheel and Mr. Latrobe's sketches. I have finished two of them and placed them on two of the wheels with a piece of lumber so you can see how it will end up looking (kind of). I'm going to order some more rod for the axles, the rod I have is 3/8 inch stuff and I really only need 1/4 inch. I may still make the axle for the drivers out of the 3/8 " so I can build in a stop for the gear, but I don't know if that will make much of a difference. 











Thanks,

Jason


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## Grimm (Oct 5, 2009)

I was just starting the axle when I realized that I'm not sure just how to attach the wheels to the axles. I know that most people press-fit the wheels on, but I don't think that my skill is anywhere near that level yet. I don't have an arbor press either, and I'm not sure my regular vices would work well with the outside journals. Peter Jones in his book talks about gluing the wheels on with epoxy and I liked how redbeard fixed his wheel by drilling a hole in the axle and wheel and then inserting a pin. Any recommendations? Thanks,

Jason


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## xo18thfa (Jan 2, 2008)

In Gauge 1 sizes, Loctite #680 works fine to stick wheels to axles. Pressing fine iron castings is not a good idea. They could easily crack. The press tolerances are tough to meet.


How are doing the axles? One way I've done it is to turn a 40mm length of 1/4" rod. 40mm is the back to back on the wheels in Gauge 1. Then drill/ream a 3/16" hole on each end and loctite in a length of polished stainless rod. Loctite the wheels on the stainless rod, up tight against the inner axle.


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 29 Dec 2009 01:41 AM 
Hi Bob, thanks. That is the truth isn't it.







I have finished all of the wheels. Whew! I think I may have made the flanges short, hopefully not too short.







I also cast up the journal boxes that are based off of the early version of Winan's friction wheel and Mr. Latrobe's sketches. I have finished two of them and placed them on two of the wheels with a piece of lumber so you can see how it will end up looking (kind of). I'm going to order some more rod for the axles, the rod I have is 3/8 inch stuff and I really only need 1/4 inch. I may still make the axle for the drivers out of the 3/8 " so I can build in a stop for the gear, but I don't know if that will make much of a difference. 

>>> photo left out


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## Steve Shyvers (Jan 2, 2008)

Jason, 

I haven't attached wheels to axles with Loctite - yet - but one bit of advice I read was to cut a small groove around the axle where the wheel will be such that when the wheel is in its correct position it covers the groove. The groove will hold additional Loctite to add strength to the bond. Apparently with Loctite you need a gap between the bonded surfaces for the Loctitie to go into. With a wheel on an axle you want the fit to be as close as possible so they stay concentric, but without a groove there isn't enough gap for the Loctite to go into so the bond isn't strong. 

A comment on the 40mm back-to-back dimension: that's as measured between the backs of the wheel rims and assumes a flange profile close to the G1MRA standard. If the backs of the wheel's hubs are not coplanar with the backs of the rims then you'll need a different length axle if you follow Bob's axle method. 

I did successfully press fit my cast iron wheels onto a mild steel axle, but then I was dealing with only two wheels and one axle. Also I probably spent 3 hours turning the axle so I could sneak up on the correct diameter to make a press fit. 

Steve


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## xo18thfa (Jan 2, 2008)

There is an art to using loctite. Steve is right about the tolerances. If the wheel fit is too close you will just wipe off the loctite and the joint will be dry. It will fall apart right away. Too loose and the wheel may end up out of concentric. Some brands of loctite do not do well with big gaps. #680 is pretty forgiving. The axles should be .002 or .003 smaller than the inside of the wheel hole. The reason I mentioned a built up axle is because a drilled hole almost always gives the right loctite clearance with the shaft material. Put the shaft material in the lathe and rub it down with 600 grit paper and oil is all the polish it needs.

You can turn axles from solid too. It helps to use "free machining" steel. Alloy 12L14 steel or 303 stainless. Whatever material you use, take plenty of time, super light cuts on the last several passes and use oil.


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## Grimm (Oct 5, 2009)

Thanks guys,

I will look and see if my local industrial supply shop has loctite #680. 


I have been following the NMRA SA3 and SA4 standards for F-scale (1:20.32), which I think is a little bit larger then Gauge3. Would that make any difference in the use of the loctite? The journals are .177" (4.5mm) in diameter, the wheel hub landing (?) is .25" in diameter and the main axle shaft will be a bit larger (although I haven't machined it yet) as I was thinking that having a landing would help keep the wheels concentric. The rod I'm using is, according to the label, tool steel but I don't know the exact alloy. Currently the hub landing is .002 inches larger then the drilled hole in the wheels. My drill bit was .26 in diameter instead of .25 ?!? I will machine them down to .258 and go from there.

Thanks for the flange information that is very similar to the NMRA standards. I measured mine and they are about .051" (~1.3mm) so right at the minimum for NMRA SA4, my problem was that I forgot that you need to take the difference between the rim and the flange and divide it by 2 to get the correct flange height. Lucky for me I thought to myself that they were starting to look pretty small and stopped when I did.









Steve - So would the best place to put the groove would be right at the half-way point of the hub ?


Jason


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## xo18thfa (Jan 2, 2008)

Jason: A local machine shop or big auto parts store may have #680. Check out McMaster Carr. They have all the odds and ends stuff. They have a chart of loctite products and a different type may have the same results as #680. Go to the store with options. I got #680 as a shot in the dark and it works fine. A one ounce bottle of loctite will last years. Some loctite brands can be dis-assembled with heat. I don't think #680 can. If you run into trouble with too shallow flanges, re-turn the treads on the wheels. But from what you are saying, it sounds like you have a handle on it. Most tools steels turn fine. I have discovered that our smaller lathes cut better at slower speeds and with oil. Regular 30 wt oil works fine, again one quart lasts a life time.


http://www.mcmaster.com/#


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## Grimm (Oct 5, 2009)

Well I wasn't able to find loctite #680, but I did find some loctite #330. It is in two parts, an accelerator that you spray on one side and a resin that you apply to the other. The resin is very thick and sticky. It handle hardens in about 1 min and is fully cured in 4 to 24 hours. It applied fairly easily and is still holding the wheels on to the axle. It is supposed to be as strong as steel once it is hardened. I guess I will see how it holds up, eh?







Here are a couple of pictures of the wheel set, my very first one too.



























Jason


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## xo18thfa (Jan 2, 2008)

Dude, what's wrong with those?? They look perfect. Looks like they ended up square to the axle shoulder. How do they look on a test roll?

Hard part is over. 

(What about sprockets?)


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## Steve Shyvers (Jan 2, 2008)

Jason, 

Apologize for getting back to you so late, but it sure looks like you knew what to do all along. That wheelset looks great! Did you cut a groove for the loctite? The location isn't critical, which you've already figured out. 

Steve


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## Grimm (Oct 5, 2009)

Thanks Bob,

I forgot to add that I did trim down the tire to get better flange height, they are about .062 inches now and the rims are still close to 30 inches prototypically (29.5"). On the test roll do you look for wobbling, etc? I did roll it across the floor and did not see any misalignment, it looked very straight. I don't have a long enough track made yet to do a proper roll on track. I tried to take the wheels off of the axle this morning and was not able to, so far so good.







Sprockets?!? I'm thinking The Jetsons, are you thinking of the journal bushings?







I was thinking of not having bushings for the journal boxes because they are made of white metal. Is that not a good idea? The snow plow has journal boxes made from the same stuff and it rolls very smoothly. 


Steve - No I thought I would try it with out the groove just to see how this loctite 330 worked without one. I left the hub landings on the axle rough from the lathe and didn't file or sand them in the hope of giving the loctite more grip. It appears to have worked pretty good, either that or I just got lucky.







I still don't feel like I know what to do, so any advice is very much appreciated. Thanks,


Jason


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 31 Dec 2009 06:35 PM 
Thanks Bob,

I forgot to add that I did trim down the tire to get better flange height, they are about .062 inches now and the rims are still close to 30 inches prototypically (29.5"). On the test roll do you look for wobbling, etc? I did roll it across the floor and did not see any misalignment, it looked very straight. I don't have a long enough track made yet to do a proper roll on track. I tried to take the wheels off of the axle this morning and was not able to, so far so good.







Sprockets?!? I'm thinking The Jetsons, are you thinking of the journal bushings?







I was thinking of not having bushings for the journal boxes because they are made of white metal. Is that not a good idea? The snow plow has journal boxes made from the same stuff and it rolls very smoothly. 


Steve - No I thought I would try it with out the groove just to see how this loctite 330 worked without one. I left the hub landings on the axle rough from the lathe and didn't file or sand them in the hope of giving the loctite more grip. It appears to have worked pretty good, either that or I just got lucky.







I still don't feel like I know what to do, so any advice is very much appreciated. Thanks,


Jason 


0.062" flange will be fine. The G1MRA "Fine Scale" standard is 0.060". No, test roll on that track is just to hear the wonderful sounds they make. I don't remember if this engine is a chain drive. If so, the chain sprokets go on the axles before the wheels get glued on. Journal bearings are not a bad idea. Loctite or epoxy some short lengths of brass tube. Alignment is important. Since it appears your journals are blind, build up a little jig to hold a journal in place plus an alignment rod. Slip a bearing over the rod and a "TT" of loctite on the bearing. Slide the bearing into the journal and leave it sit until dry. The alignment rod will keep the bearing straight.


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## HMeinhold (Jan 2, 2008)

Jason, 
I second Bob's suggestion to use brass bearings. The white metal will wear out too fast if the axles are not highly polished. Good luck and keep having fun with your project. 
Regards


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## Grimm (Oct 5, 2009)

Thanks again guys,

I will put some bearings in the journal boxes, would copper work as well as brass? I have some copper on had but no brass in the right size. I finished the axle for the drivers, this is the second one I made. The first one was not concentric, I think I made it in the wrong order and it became out-of-wak. 




















I haven't glued the gear in yet so that I have some wiggle room when I connect up the engine. 

Jason


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## Pete Thornton (Jan 2, 2008)

jason - great looking track!


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## Grimm (Oct 5, 2009)

Thanks Pete,

Well the vacation is over, so work on the engine has slowed considerably.







All of the wheels and axles are done, bearings have been put in the journal boxes, and I have started on the frames.










The passenger car frame is farther along then the loco's. It's around 9.25 inches long, prototypically it was supposed to be 15 feet long and was able to sit 15 people although on the first run of the locomotive in August 28, 1830 is was said to have carried around 20 people (24 minus the engine attendants). I have tried to follow with the Latrobe sketches but still have the basic outline of Mr. Imlay's later designs. 











And a close-up of the journal boxes that are also a combination of Mr. Latrobe's sketches and the earlier versions of Winan's friction wheels that are illustrated in his patent from 1828.










Jason


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 01 Jan 2010 09:50 PM 
Thanks again guys,

I will put some bearings in the journal boxes, would copper work as well as brass? I have some copper on had but no brass in the right size. I finished the axle for the drivers, this is the second one I made. The first one was not concentric, I think I made it in the wrong order and it became out-of-wak. 








I haven't glued the gear in yet so that I have some wiggle room when I connect up the engine. 

Jason


Use brass, or bronze is even better. Copper is too sticky. When it comes to materials, the first engine project is the most costly. The next one you won't need to get as much, if any.

The wheels look perfect. If they wobble a "TT" don't worry about it. Only you will notice.


Did you cut the webs in the gear? Looks nice.


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## Jerry Barnes (Jan 2, 2008)

Looking good. What wheel turning technique did you use? I plan to turn some next week. Finally warming up some here in Neb!


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## Grimm (Oct 5, 2009)

Bob - Thanks for the nice comment on the wheels, you know how it goes, I already can see better ways of doing things.







I will get some bronze for the bearings and leave the copper in for the mean time. I think they should come out fairly easily. Yes I did cut the webbing on the gear, I wanted it to look more like the larger originals, thanks.

Jerry - Thanks, I followed the method described by Peter Jones in his book "Building small steam locomotives". It's pretty straight forward, I just faced off the back of the wheels, then the front. I then centered the wheels as best I could and drilled the axle holes. I then made a mandrel, the end I threaded so I could bolt the wheels on to it with some brass nuts and cut the rim and flange. The last thing I did was to cut out the back to help expose the spokes. Hope this helps, I so new to all of this I don't want to miss-lead you and take you in a not-good direction.







I wish it was warming up here in Fairbanks, It's been warmer then usual, but still down around -12F. It's usually down around -40F this time of year (or colder







).

Jason


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## Grimm (Oct 5, 2009)

More progress on the frames, both are finished and the car frame is painted. I have painted the wheelsets as well. 



















Here is a close up of the coupler (pin devise?), I based it off of the ones on the flour cars and the Ohio/Pioneer passenger cars. 










I made the floor removable so I could maintain the wheels, etc. The floor is attached with two #1 lag bolts and washers. 











I need to order some more parts for the locomotive and a new gear then I can continue on it. In the mean time I'm going to finish the passenger car. Would the ball bearings that Charles bought up in his thread work for these journals? I'm thinking of getting some, I think all I would have to do is drill out the journal holes some to get them to fit. 


Jason


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## xo18thfa (Jan 2, 2008)

Looking real good Jason. Painting as you go is a good idea.

Give the ball bearings a try. Anything that reduces friction is a good thing. Somebody has to try something new first.


I don't remember, but what is the plan for the power unit? Now that the chassis is pretty much rolling, that's coming up soon

Bob


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## Grimm (Oct 5, 2009)

Thanks Bob,

I will order some of the ball bearings then, a package of 10 was only $20 and that will cover all I need with 2 left over.







The power unit is going to be (or I'm going to try to do) a vertical boiler and cylinder. The cylinder will have a long "D" valve and an overhead crosshead which was normal for the 1820's and matches Mr. Latrobe's sketches. I'm thinking of controlling the valve motion with an eccentric, to give me some experience making them. The boiler will be very small, even at F-scale, so I don't know if it will even be able to produce the steam necessary to move the loco. At the very least it might look good and it will again give me more experience constructing boilers. The drive shaft of the engine will have a spur gear that will connect to the spur gear on the wheelset. Here is a rough sketch I doodled of the engine's cylinder and valve.











Jason


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## xo18thfa (Jan 2, 2008)

Jason: That is a nice looking engine design. I am guessing the exhaust on the upper side vents thru the hole in the valve spindle. That should work just fine and give it a cleaner look. I think the cylinder would be a straight turning job so you have the flanges for the top and bottom cover. The valve body, stem in, exhaust out and passage tubes can be cut from solid. Turn as much as you can on the lathe, then finish up with hand files. That will be a long tough job, but patience and art of using hand files is a skill well worth developing. Silver solder the two parts together. 

When you say small boiler, how small? What's the plan? In most cases a little deviation from prototype is OK.


Bob


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## Grimm (Oct 5, 2009)

Thanks Bob, you make it sound so easy.







Here is a rough sketch of the boiler I was thinking of building. The original was supposed to have been about 20" in diameter and around 5 to 6 feet tall. I went with the taller height so that I had more room for the steam, and I will mount the boiler about .5" bellow the floor of the loco so that it will look shorter then it is. The only type L pipe I could find that matched the scale diameter of the boiler was some 1.125" copper pipe. It's a smidgen bigger then the prototype, but again it gives me a bit more room. I have some 3/8" pipe for the flue and some 16 gauge copper wire for the quills, which hopefully will help with the steam production. Please let me know if you have any better ideas to improve it.











I made some more progress on the passenger car's sides:



















Thanks,

Jason


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## xo18thfa (Jan 2, 2008)

It's hard to tell if the boiler is too small or not. Depends on the bore/stroke of the motor. The good thing about the design is that it modular. You can do the motor and boiler separately and then bench test them. If the combo works, you are good to go. There are successful steamers in HO and even N gauge. 

Boiler should have the maximum heating surface possible. Wetside fireboxes are usually better than dryside. An idea may be to use a "reducing T" plumbing fitting for a firebox and door. Something like this:










The cross piece is a tube with water circulating thru. 

Do a paper/cardboard mock up of the boiler. If a large boiler looks good a larger size would never hurt.



Bob


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## Grimm (Oct 5, 2009)

You do make a good point with the HO and N gauge live steam engines, they use electrical heaters don't they? I was thinking of using the Esbit solid fuel tablets to heat the boiler and have a working blower to increase the heat, good or bad idea? Or would it be better to just do butane? I'm thinking alcohol would be out because of all the wood. I like your idea of using a wetside firebox, although I'm a little concerned that it will shrink the combustion area a lot and be more difficult to build. I'm going to make a trip to the hardware store and see what I can find in the pipe fittings and see if there is something that will work. Heating the water with electricity would be ideal, because then I could emmerse the heating elements in the water and use all of the remaining space for water and steaming room. I don't know how much power that would take though, and I have no plans of putting track power on my layout so it would have to be powered by batteries. Thanks again for all of your help in this as I'm clueless and I know I'm going to have to make a desision soon before I can start constructing the boiler. 

Jason


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## Pete Thornton (Jan 2, 2008)

I was thinking of using the Esbit solid fuel tablets 
One word - don't, for all kinds of practical reasons: changing the tablet when it is done and the boiler is hot, supply reliability, etc. The old Mamod tablets used to absorb water, if my memory is correct, which made shelf life a bit of a problem. 

Brittany's photo set from Cabin Fever has this pic of an HO Mallard, which has a small boiler in the tender heated by track power. So It can be done, though the batteries would have to be large. 

*[url]http://gold.mylargescale.com/peteth...80-800.jpg*[/url] 

Take a look at an Accucraft Ruby, which is a very small loco and has a small square butane tank in the cab. David Wegmuller used it with a circular burner - see his page of info: *[url]http://wegmuller.org/trains...l*[/url]

You could disguise it as wood storage or put it in the water barrel? A small circular burner and a flue, like Bob's drawing, should work. The BAGRS loco *[url]http://www.panyo.com/mso/BPE.htm*[/url] 

and the Midwest Steam boiler may give you ideas. *[url]http://www3.towerhobbies.co...8*[/url] 
And finally (isn't Google wonderful) there's Kevin O'Connor's radiant burner for a vertical boiler: *[url]http://www.southernsteamtrains.com/notes/radiantpokerburners.htm*[/url]


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## xo18thfa (Jan 2, 2008)

I just remembered a small vertical boiler engine that is very popular with the 16mm and 7/8 crowd. Check out Dave Watkin's "Idris"

http://www.davewatkins.pwp.blueyonder.co.uk/steam.htm

Gas burners can get small too. I saw a little ceramic burner a guy made for a vertical boiler that was only .5" dia. It may be possible to cannibalize a Harbor Freight pencil torch for parts. A custom made butane tank should not be any harder to make than a boiler.


http://www.harborfreight.com/cpi/ct...mber=94185 
I did not know about track powered electric heated boilers. Learn something everyday. I suppose it's a nichrome wire element.


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## rwjenkins (Jan 2, 2008)

Another problem with Esbit, in my experience anyway, is that it doesn't burn very cleanly. I have a tiny model steamboat with a 1" diameter by 2" long horizontal pot boiler that I used to fire on Esbit. The bottom of the boiler would get a thick build-up of caked-on soot from the esbit, and every half-dozen runs or so, I had to remove the boiler for cleaning because the soot build-up wasn't letting enough heat through. I now have it set up to run on Sterno, which doesn't burn as hot but at least it burns much cleaner.


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## Grimm (Oct 5, 2009)

Thanks everyone, ok, no Esbit tablets then.







I like the idea of going with a ceramic burner as I was thinking of using them in larger engines I might make one day. Bob, the pencil torch looks like a great idea, and at that price I might as well get several and see how they work. The butane tanks on them just might be small enough to tuck in the frames and under the floor of the loco. Pete - according to one of the Latrobe sketches there was a coal bin at the rear of the engine that might be a good place to hide the butane tank as well. I found a piece of pipe that will work well for the firebox and I have ordered some hard silver solder. The only things I'm missing are the boiler fittings that I will need. Does anyone know of a good place to purchase a safety valve (40 PSI)? It needs to be very small, no more then 1/4" wide at it's largest diameter. Does such a thing exist? 

Also I'm still a lot confused at to how the bushings work. I was thinking of just soldering the steam pipe to the boiler, but I also would like it to be easier to fix and maintain the boiler too. What are the standard sizes and what is the best way to make the connections from the pipe to the bushing? Thanks again, now I'm getting more comfortable with the boiler plan.









Jason


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## xo18thfa (Jan 2, 2008)

Bushings serve as a means to screws fittings onto the boiler weldment. They are made of bronze and bronze only. At a bare minimum you would need 2 bushings. One for the safety valve and the other for an angle or globe valve to serve as the throttle. You can remove the safety to fill the boiler.

Finding that small of a safety valve commercially may not be possible. The smallest I've seen are 1/4" threads and 3/8" or 7/16" hex body. I remember in a very old Popular Mechanics where a guy built a small steam power plant and used a cork for a safety valve.


Check out P.M. Research. They have a wide variety of fittings, pretty much everything commercially available. They have some very nice scale pipe fittings that may look good on you engine.

http://www.pmresearchinc.com/store/home.php


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## HMeinhold (Jan 2, 2008)

Jason, 
I can second again Bob's suggestion to copy "Idris" features. I built the boiler for my A-Climax using Dave Watkin's ideas. See: 

http://wegmuller.org/trains/friends/index.html 

The loco with this boiler climbs 10% grades with 2 pairs of disconnects. So your original boiler design should work, however I would increase the flue diameter to 1/2". I also don't like to use the fairly thick-walled copper fittings. I feel, thinner tubes steam more freely. Bob, what is your experience with thick walled copper? Ceramic burners are the way to go. My Climax is equipped with such a burner. You can find a drawing of our donkey burners on David's WEB site, see: 

http://wegmuller.org/logging/index.html 

Regards


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## Grimm (Oct 5, 2009)

Thanks Bob, I guess I understand about the bushings themselves and I see that PM Research has some for sale, I'm assuming that I would need the 1/4" ones. Thanks for the information about the globe valve for the throttle, that was another questions I had.







The questions I do have is what size of tubing for the steam lines, 1/8"? And how do they connect up to the bushings? Do you flare the ends of the tube or is a nipple soldered on to the end? I don't see these things for sale anywhere and where do you get the packing nuts if they are needed? The 3/8" safety valve just might fit, or I guess I could put the valve on a stem to give it more room? It looks like PM Research only has a 60PSI one that is too large. Sorry for all of the questions, I just want to do this as right as I can.









Here is a quick cad drawing of the boiler, I incorporated your ideas on this Bob. The angle brackets are positioned on the floor. The measurements are in inches.











Thanks Henner, 

I have looked at your sites before and I really like your donkey engines and the climax. Do you really think I need to make the flue 1/2" in diameter? I only ask because the smaller flue I have already takes up a lot of room in side the boiler. I don't know if there would be enough room for any water and steam with a 1/2" flue. Are you thinking that there will not be enough draft for the burner? I only went with the type L pipe because everything I read said that you needed that type for safety. Although I have seen the internal flues done with 20 gauge walled pipe which is pretty thin, much thinner then the type L stuff. It gets very confusing, too many options.









I thought I would add that the dimensions for the cylinder that I was thinking of using are 3/16" in diameter and a .7" stroke. This matches the original fairly closely in proportion although the diameter is a little larger.

Jason


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## Pete Thornton (Jan 2, 2008)

Does anyone know of a good place to purchase a safety valve (40 PSI) Roundhouse sells parts - not quite 1/4": "SV - Safety valve threaded 5/16" x 32 40 psi blow off" *http://www.roundhouse-eng.com/* 

Ralph Reppingen makes boilers and fittings in Germany - we've had fun ordering his check valves. If you can handle german (Babelfish is quite useful,) he can possible help.
*http://www.reppingen.de/lieferprogr...index.html*


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## Pete Thornton (Jan 2, 2008)

Jason, 

Our little engines use the same techniques as big boilers. Check out the plumbing standards and techniques, and you'll find out about "Pipe Nuts and Ferrules", "Unions", "Nipples", etc., etc. 

The other place to learn is to take an Accucraft loco apart - or search MLS for articles and threads about the Accucraft Ruby and Shay. 

Basically, you need to silver-solder a threaded bush in a hole drilled in the boiler. [Disclaimer: I've never built a boiler. Email Justin with questions - he has. Username "slippedeccentric".] The threads can be inside or outside, depending on what you plan to screw onto/into it. Many locos have only one bush (besides the safety valve, of course,) with a hollow 'manifold' made of brass screwed into it. (A fiber washer often seals the joint.) Various take-offs are screwed into the manifold: pressure gauge, steam line to oiler/cylinders, blow-down,etc. 

what is the best way to make the connections from the pipe to the bushing? 
A pipe nut goes over the pipe, you then flare the end of the pipe slightly and the nut squeezes it onto the union. (Did I get that right, you plumbers?) A ferrule does much the same thing, but is soldered to the end of the pipe and squeezed by the nut into a depression in the end of the union. 
Copper pipe is used as it is easier to bend cleanly. I get mine at Ace Hardware - from the K&S small metal bits display.


Try Steam fittings in the UK: *http://www.steamfittings.com/asp/index.asp*. 
They sell ferrules, unions, boiler blanks, etc. 

Small Parts sells brass fittings and quick-connects: *http://www.smallparts.com/*

Here's a useful thread about scratchbuilding a steam engine: 
*Live Steam Forum/Topic: Scratch building a Live Steamer*


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## xo18thfa (Jan 2, 2008)

Posted By HMeinhold on 20 Jan 2010 10:16 PM 
Jason, 
I can second again Bob's suggestion to copy "Idris" features. I built the boiler for my A-Climax using Dave Watkin's ideas. See: 

http://wegmuller.org/trains/friends/index.html 

The loco with this boiler climbs 10% grades with 2 pairs of disconnects. So your original boiler design should work, however I would increase the flue diameter to 1/2". I also don't like to use the fairly thick-walled copper fittings. I feel, thinner tubes steam more freely. Bob, what is your experience with thick walled copper? Ceramic burners are the way to go. My Climax is equipped with such a burner. You can find a drawing of our donkey burners on David's WEB site, see: 

http://wegmuller.org/logging/index.html 

Regards 
Hi Henner: Thanks for posting the link to your Climax. Very informative. I like the way you used the Mamod for a test run. I don't like thicker copper either. I would really fabricate the whole thing, but for the sake of simplicity, suggested a "T" fitting. 

Question for you, what would you do for a ceramic burner on this project? And, what is the smallest gas jet hole you drilled on your sensitive drill?


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 21 Jan 2010 01:55 AM 
Thanks Bob, I guess I understand about the bushings themselves and I see that PM Research has some for sale, I'm assuming that I would need the 1/4" ones. Thanks for the information about the globe valve for the throttle, that was another questions I had.







The questions I do have is what size of tubing for the steam lines, 1/8"? And how do they connect up to the bushings? Do you flare the ends of the tube or is a nipple soldered on to the end? I don't see these things for sale anywhere and where do you get the packing nuts if they are needed? The 3/8" safety valve just might fit, or I guess I could put the valve on a stem to give it more room? It looks like PM Research only has a 60PSI one that is too large. Sorry for all of the questions, I just want to do this as right as I can.









Here is a quick cad drawing of the boiler, I incorporated your ideas on this Bob. The angle brackets are positioned on the floor. The measurements are in inches.





Thanks Henner, 

I have looked at your sites before and I really like your donkey engines and the climax. Do you really think I need to make the flue 1/2" in diameter? I only ask because the smaller flue I have already takes up a lot of room in side the boiler. I don't know if there would be enough room for any water and steam with a 1/2" flue. Are you thinking that there will not be enough draft for the burner? I only went with the type L pipe because everything I read said that you needed that type for safety. Although I have seen the internal flues done with 20 gauge walled pipe which is pretty thin, much thinner then the type L stuff. It gets very confusing, too many options.









I thought I would add that the dimensions for the cylinder that I was thinking of using are 3/16" in diameter and a .7" stroke. This matches the original fairly closely in proportion although the diameter is a little larger.

Jason 




Hi Jason. Henner suggests a 1/2" flue and I agree. You may need the extra heating surface of a 1/2" . The downside is the fire will go thru it like p**p thru a goose. Try using a "turbulator" in the larger flue. A turbulator is a thin piece of sheet metal twisted like a candy cane and dropped down in the flue. It will slow down the fire and keep it in the flue longer. You would have to experiment with the twist and length to get the most optimum set-up. Build a test flue and experiment with it using the burner you select. Once you get everything right, the flue assembly can go straight into the boiler shell. Try both size flues and see what happens.


Pete's link to the U.K. fitting company is a big help. They appear to have a better selection than PM Research.

1/8" pipe should be plenty. With a .19 bore and .7 stroke, 3/32" may even work. 1/4" bushings, they would take the sized fitting you would use.


I have never used commercially made fittings. I do my own. But the ones I have seen usually come with a nipple (ferrule) that you would solder to the pipe. No flaring needed. The fittings from Pete's link look that way. The ferrule appears to be installed with the union nut.


The cross piece I showed in my drawing is actually a tube. 3/16" or 1/4" dia. Water flows thru it and gets super heated by direct flame.

The PSI they show on the safety valve is what it set at by the manufacturer. They are fully adjustable from zero to total clamp down. 


Has anyone has ever tried a "dead weight" safety valve. Free weights used rather than a spring to hold the valve spindle down. You could make a very thin valve that way. "Old school" U.K. builders before LBSC sometimes used them. You could be a "back to the future" pioneer. For a boiler this small, a safety valve opening would only need to be about 1/16"


I saw on the internet a guy who made a ceramic burner from a 1/2" copper pipe cap trimmed down to about 3/8" tall. Packed it with fire brick. Why wouldn't that work? 


Bob


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## xo18thfa (Jan 2, 2008)

If I did the math right, here's the difference between a .375" and a .500" flue. The smaller flue gives 12% more water space. The larger flue give 11% more heating surface, the amount of heated firebox in contact with water.

I would go with more heating surface. More heat is generally better.

There is no right answer Jason. Options and trade offs. You are blazing a trail buddy.


That's why they used to call High School shop class "Industrial ART"


Bob


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## HMeinhold (Jan 2, 2008)

Jason, 
I just consulted "Building Simple Model Steam Engines" from the legendary Tubal Cain. 2 boilers come close to yours: 
#1: 1 3/4" inner diameter, 3 1/4" high. Flue 1/2" inner diameter, 24gauge for boiler, 22gauge for flanges. 
#2: 7/8" outer diameter(!), 1" high. Flue 5/16" outer diameter. 26gauge for boiler, 24gauge for flanges. 
But as Bob mentioned: It's an art. Don't feel bad if your first boiler does not steam properly. We have all gone through this experience. I once built a highly sophisticated loco boiler, which did not steam at all. The simple pot boiler built by my son however made the loco fly! Pretty embarrassing. 
Regards


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## Grimm (Oct 5, 2009)

Thanks guys,









I updated the boiler design using the 1/2" flue. I also shortened the firebox, do you think that 1" would give enough clearance for the ceramic burner? 











I found a 3/4" end cap for the burner that fits tightly on the 3/4" firebox pipe, I was thinking that I could put a couple of screws in it to keep it on the boiler. This is why I extended the firebox down a bit to give room to attach the burner. 


The only thing I worry about is the smoke stack. Can I use the smaller diameter pipe (3/8") for the stack? Anything larger would not match the original very well. I was thinking that it might help to slow the heat down a bit as well and I was going to have a small smoke box space above the boiler. Would this work ok? 


I would like to make my own bushings for the boiler, Bob, do you have any photos of the ones you have made, or some designs. I would love to see them.

Thanks Pete, those links are very helpful.

Jason


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## xo18thfa (Jan 2, 2008)

With what Henner just said, it looks like a 3/8" would work fine. I would just do both and use the one that gives best results. Bench test the whole drive unit before installing on the chassis.


Gas burners need 2 sources of air. A primary source, which is the holes in the tube around the jet. And an ambient source which is the air around the flame. Your idea to fit the cap into the fire box is good, just be sure to drill a row of holes around the edge so extra air can get directly to the frame.


I was just wondering if a super fine needle valve from an old Cox .049 glow plug engine carburetor would work for gas control valve. They are very tiny and fairly sensitive.


This is the 1/4" bushing I use. I use phosphor bronze, but regular (932) bronzes works too.










It is probably too big for your boiler. You could reduce the smaller dia to 5/16" and the larger one to 3/8" The safety bush should go directly on top. The throttle bush goes on the side very near the top.


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## xo18thfa (Jan 2, 2008)

Jason: This is the smallest double acting steam engine with a published plan I am aware of. It was designed and built by the late Phillip Duclos. It has a 1/4" x 1/4" stroke with a 1/8" dia piston valve. The flywheel is 3/4". Even tho it is not the bore/stroke you need, his techniques and methods may be helpful. Get with me off the board if you would like a copy of the article.










Bob


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## HMeinhold (Jan 2, 2008)

Posted By xo18thfa on 21 Jan 2010 02:20 PM 


Question for you, what would you do for a ceramic burner on this project? And, what is the smallest gas jet hole you drilled on your sensitive drill? 


Bob,
sorry for the late reply: I would just use a scaled down version of the donkey boilers. The top of the ceramic should be about 1/2" to 3/8" from the top of the firebox or in this case from the cross tubes.

The smallest holes I drilled with my jewelers lathe were 0.15mm or about 6/1000"
Regards


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## Grimm (Oct 5, 2009)

Thanks again everyone,

Henner - That is one very small hole!!









This is a big update, I have not been feeling well, so I haven't kept up with the postings. Not that I didn't try and get some work done on the project though.









The bearings came in and I have put them on the loco but not the car yet. Much better, much less friction then before. I have been working mostly on the car while the parts for the loco come in. Here is an overview of the project so far:











Here is a close-up of the bearings, they came in a plastic tube. They are pretty amazing just how small they are (5/16" diameter, 1/8" thick, .188 bore).











The car is coming along nicely, the walls and the roof joists are up. 











I have finished one of the benches and installed it. They are made from mahogany which I sanded smoothed and waxed.


















The loco's frame I changed to better reflect the new information I keep uncovering.







I was able to re-use some of the old frame, so it wasn't too bad.











Jason


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## xo18thfa (Jan 2, 2008)

Very nice Jason. Beautiful work. What goes on the roof of the passenger coach?


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## Grimm (Oct 5, 2009)

Thanks Bob,

I'm not sure, to tell the truth. My plan is to put planks down, length-wise, and then cover them with something. I'm assuming they used tarred canvas or something similar to cover and water proof the roof.


Jason


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## xo18thfa (Jan 2, 2008)

Maybe bed sheet, died black would work for canvas in that scale. A spray adhesive (?) It would be a little texture, but not overpowering. Clearly need something finescale.


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## Grimm (Oct 5, 2009)

Excellent suggestion Bob, I found some muslin that I had on hand that I think worked out pretty well.







I haven't had much time to work on the project, but I was able to get some time in and almost finished the passenger car. The loco is in pieces right now, but I'm slowly getting more of it finished too. I chipped one of my end mills, so I'm waiting on a replacement.







I have ordered a 4-jaw chuck and the pencil torches for the burner. I need to finalize the plans for the engine and pass it by you guys. Here are some pictures of the passenger car.




























One of the ends, the other bench, roof, and the 15th seat are done and finished. On the loco I have finished the frame and some of the decking. In the picture you can see the brass plate that I'm going to attach the boiler to and the boiler tube sitting in it's hole. Eventually the boiler will have brackets that will be bolted to the brass plate. I have started the brackets for the crank shaft that will bolt to the underside of the frame. The coupling pins have also been attached to the frame. I still need to install the roller bearings on the car, that will happen once I get in the new endmills. 











Jason


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## Grimm (Oct 5, 2009)

Well this weekend was a bit frustrating.







I got in the new 4-jaw chuck, cleaned and mounted it on the lathe. Spun it up for a test run and it shook the lathe like a wet dog. Because the chuck is a 4" one it needs an adapter to mount it on the 7x12 spindle. I thought that I must have mounted the adapter wrong, so I took the chuck back down and took a look at the adapter. It didn't have any side-to-side slop at all, so I turned it counter clockwise one screw hole and put it all back together again. This time the shaking was much reduced, so I may take it down again and turn the adapter another screw hole and see if it gets any better. Do they usually custom match these adapters to the chuck? I bought this from the Little Machine Shop by the way. 

The other problem was that when I tried to start making the crank shaft I discovered that my bar stock is much too short to use the steady-rest. So I thought that I would at least face the ends off. Now I have figured out that I'm not good at all at making my own tool bits.







So I have on order a follower-rest and some 1/4" indexed carbide tool bits. Well there is always next weekend.









Jason


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## xo18thfa (Jan 2, 2008)

Yes, they usually are. But even still, it should not shake that much. If you get the bolts lined up and the shaking stops, punch 2 marks on the chuck and adapter so you line them up the same if you ever have to take it apart.

Oh, the challenges of machine work.


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## Grimm (Oct 5, 2009)

Thanks Bob. I exaggerated the shaking, but it was enough for me to think that it was not good.







I will definitely mark the chuck so it can be put back together correctly. Now just to find some time to do it.









Jason


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 17 Mar 2010 07:50 PM 
Thanks Bob. I exaggerated the shaking, but it was enough for me to think that it was not good.







I will definitely mark the chuck so it can be put back together correctly. Now just to find some time to do it.









Jason 


Another thing about 4 jaws is that the work piece almost always goes in off center. There will always be some eccentric wobble. Sometimes you even have to balance the set-up with counter weights or you could send you and the lathe out the window.


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## Grimm (Oct 5, 2009)

That makes sense, thanks again Bob.







I received the pen torches, very cool, and they work too which is always a plus. Thank you for suggesting them, I think they will work for what I need. They are not the best built, but what can you say about it when it only cost 5$, so I bought 3 just to be sure. They have an aluminum body or tank that was a bit longer then I had hoped but it worked out ok in the end. On one end you have a butane filler valve and at the other end is a brass flow control valve and the torch head. You rotate the valve head to turn the gas on and off. 











The torch was much too long to fit the entire thing into the loco's frame, so I striped the paper covering off of the body and cut the torch head off like this:










Next I had to figure out a way to fit the tank into the frame. To do it I had to cut away two of the supports and bolster them up a bit:




















The tank sits nicely in the frame although there is just a hairs breath between it and the wheels/axles.







Next I made some hangers to hold it to the frame:










This brought up a problem that I didn't have a good solution for yet, that is how to regulate the gas flow? I thought that it would be great to use the exsisting one and not have to add additional equipment. So what I did was to build a hanger that also had a hole to hold the pin on the torche's valve. This way I can turn the tank at the fill end to turn the gas flow on and off. It works pretty good so far, we'll see when I have the boiler made and can test it. Here is a close up of the hanger and the pin interface.











The next picture shows the tank installed in the frame with the wheels, etc. I had some clearence issues with the rear wheels and the crank shaft brackets, so I had to further modify the frame to fix them. At this rate and all the changes, the loco will look very much like the origonal.



























These pictures give a little better view of the tight clearence in the frame:




















I then took the torch head and a 3/4" copper end cap that I intend to use for a burner and drilled a hole in it to accept the torch head:



















I'm going to make a bracket to hold the torch head to the end cap burner that will have a screw on the bottom to hold it. I'm glad I didn't start on the crank shaft until I did this, with the frame modifications I might have had to make a new one.









Jason


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## xo18thfa (Jan 2, 2008)

Nice way to hide the fuel tank.. That should do the trick. Maybe you already mentioned it, but what are you using in the copper cap burner pot? I think a chunk of firebrick is normally used. otherwise the torch will just heat the cap.

Bob


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## Grimm (Oct 5, 2009)

Thanks







Yep, I was thinking of using a chunk of fire brick, although what I have probably would not work for one very well. I was thinking that some kind of ceramic might work better, or is fire brick the same thing? I know I have seen a thread here on this, I will search for it again. 

Jason


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## xo18thfa (Jan 2, 2008)

Posted By Grimm on 24 Mar 2010 06:29 PM 
Thanks







Yep, I was thinking of using a chunk of fire brick, although what I have probably would not work for one very well. I was thinking that some kind of ceramic might work better, or is fire brick the same thing? I know I have seen a thread here on this, I will search for it again. 

Jason 


The firebrick I have is rather porous. Easy for air to pass thru. Also very soft, it cuts with a hacksaw blade. In fact, I cut some cylinder shapes one time with a serrated edge brass tube. I've seen high temp silicon used to seal the edges of the brick to the burner pot.


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## Grimm (Oct 5, 2009)

Boy howdy is this board active!







I had to hunt for my thread, I guess it's been a while.







I purchased some fire brick so I could better solder the crank shaft and boiler, etc. The fire brick I bought would not work for the burner, as they have the consistency of a cinder block. I will have to keep looking for the right kind. I did get some work done on the crank shaft. Here is some photos of the process with the help of my new follower rest. These show some of the steps I went through to make the main shaft:










































































The next image is very bad, I was lazy and didn't want to take out the tripod. So a mix of bad lighting and shaky hand held camera equals bad picture. It was to show the layout of the crank shaft arms.










The next two images show the crank shaft parts as they are finished at this point. 



















The other dilemma that I have have before I continue is to determine where to put the landing for the eccentric's grub screw. How do you determine that? Is it 90 degrees off of the throw? I need to cut a landing for the pinion gear as well, but I'm not too worried about that one. After I put these in and do a little more finish work on the arms, I should be ready to solder it together.









Jason


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## xo18thfa (Jan 2, 2008)

Jason: Probably the best way to set the eccentric is by trial and error. Try different settings until the valve event is right. It is not necessarily at 90 degrees. There is a mathematical way to determine it, but just find it the old fashioned way by looking for it. 

You are quite the machining wild man there. Looking very good. On the crank, put it back in the lathe and lightly buff with super fine sand paper or crocus cloth and oil. That will not affect the diameter at all, but remove the micro burrs that help chew up bearings.


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## doublejj (Jul 5, 2010)

Hi Jason 

I am interested in how you are getting on with your gas firing and the ceramic element. I am in the middle of building a BAGRS Project engine and wish to gas fire it. Have you got much further? How have you attached the torch head to the cup and how have you orientated it? 

Cheers 

John, Melbourne, Australia


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## Grimm (Oct 5, 2009)

Hi Doublejj,

So sorry for not seeing your post until now. I have not yet done anything else with the burner.  I did drill a hole on the side of the pipe end for the torch tip and I drilled/tapped a screw hole on the bottom. The idea was that I could have a bracket that would have one leg split into a fork that fits into one of the turned slots on the tip, the other leg would just simply have a hole for the screw to attach it to the burner. I'm assuming that the tip would just mix the air/fuel into the burner so orientation wouldn't matter and having it horizontal is the only way I could fit it into the engine. I'm also assuming you need to seal the tip in so the gas doesn't leak out and goes where it should. 


Which brings me to the subject of the engine it self. I haven't had any time to work on it until recently.  Family, life issues, etc, etc. So I started working on the engine design and thinking about things. The cool thing is that my brother, who is a jeweler, agreed to cast things I need for the engine in bronze or brass. Which is great and really opens up what I can do. The problem is that I realized my skills in building an engine this tiny are just not there yet. Even in F-scale (1:20.32) the engine is just too small and watch like for my skills. The piston would be 3/16 of an inch in diameter, the valve would be 1/8 inch if that even, with the rods being much smaller. With that in mind I decided to put this build aside and think about another engine that would be better for my experience level. Although this has been a very good learning experience and I think that the next build should go faster, now that I know a little bit more.  I will start another thread on the new build, save the parts I have built and everything else for another day. Who knows, I might just rebuild it from the bottom up. 


Hi Bob,

Thank you so much for all the help you have given me on this project. The crank didn't work out so well because I used that cheap flux/solder paste stuff.







It's probably for the better as I need to completely redesign the whole thing. And get my silver soldering skills up to snuff. I would really like your opinion on a new build if you have the time. I also have spent a lot of time rebuilding my lathe, cleaning, lapping, etc. I'm in the process of making a saddle lock and tapered gibs for it as well. Hopefully I will have a much better machine when I'm done. 


Jason


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