# Finish or Fail



## rkapuaala (Jan 3, 2008)

Well, to begin with, I bashed this Bachmann 4-4-0 a while back and below is a picture of the cab I made from Styrene









Well someone saw it (I'll let them remain anonymous unless they feel like speaking up) and asked me to make them one for their 4-4-0 bash. 
I started doing it a couple of weeks ago, and was just about to finish up the roof, when I thought to myself,
"Well, I'm planning on bashing another 4-4-0 for the same engine at an earlier period, so why not leverage his needs and my own". So I decided to save some time and make a mold.
I started this thread for three reasons; 
1. its the first time I've attempted a mold on pieces this thin and I'm not sure if I'm going to succeed. So I figured, why not share my success or failure with a step by step right here.
2. I've been so busy lately I haven't had time to contribute anything to the forum or even comment much on what I was skimming through in the morning.

3. its a chance for the person who commissioned this cab to watch my progress so he can see how far I've gotten in the months since he requested the work 
I have a few last touches to the doors and then tomorrow I'll take an image of the parts unassembled and assembled and then move on to the mold making process step by 

step.


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## Bill Swindell (Jan 2, 2008)

People who have modeling skills like your make me green with envy.

That cab is simply beautiful.


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## rkapuaala (Jan 3, 2008)

*PARTS* 








I didn't realize till I took the assembled cab shots that I neglected to fabricate the tappered rail piece that meets the roof overhang. 








I ran out of styrene and my local hobby store stopped carrying it (for some crazy reason, they can't tell me). So I decided to use some scaps of ash veneer I've had hanging around my shop for about 20 years now. You can probably see from the image that I did a little bit of form lamination. To save time, I used a 3 gallon can that was just the right diameter. I cut all the laminations to size, applied glue to one side of the first 3 layers and stacked them up and covered the last layer with some wax paper and with some packing tape I taped them all together on the can as tight as I could. 
I let it set for about 24 hours, well, at least till the next moring and glued it to the already assembled roof framing (sorry no pictures, I was too busy ) 
Its not bad, but I can see that I got a few delams going around the edge. Thats easyily fixed with a little super glue. If I wanted to spend a little more time (and if it was a real roof and not a proto I would have) I could have built a good form of plywood and a vacuum bag and vacuum form laminated the hole thing.... say, that might be a good way to go for the roof of my coach 64 (which is giving me some troubles with warping cause the stocks so thin). 








As you can see from this shot, the parts are being held together by the roof, so the parts are a little mis-aligned. 








This is a close up of the inside. I thought I would point out, that I see this as probably the single most problem area to cast, but if it works, it could save a lot of assembly time. 
What I did was to create the channel for the window to glide in instead of doing it during assemble. To keep it looking as close to prototypical the styrene is very thin and it might ended up riddled with air pockets even though I'm casting them under pressure. 
*NEXT STEP* 
cut up some material for the mold and attached the spues(?). I have some honey do stuff to finish before I move on to that though, so it'll probably be a couple days away, unless I can sneak some time.


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## Jeff Livingston (Jan 2, 2008)

Rick, 

As soon as you finish this one and work all the bugs out of the process are you going to start cabs for 76, 98, 37, and 39? Looking very, very good buddy! Hard to believe that you've been at this for such a short time even though many skills are transferable. You're a one of a kind. 

Jeff


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## rkapuaala (Jan 3, 2008)

Thanks Jeff, but I really don't deserve the praise. The only reason they come even close to the quality of work you do is because I take 10X longer than you do to finish anything








I am definately going to do 76 if this turns or if it doesn't because I'm bashing 76 and resin is a lot more durable than styrene. I wish I could afford enough connie drives and time to do the others. 
One thing, is if this works, then you shouldn't have any problems casting your coach sides like you were asking about before.


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## rkapuaala (Jan 3, 2008)

Made my first mold on the roof and have to scrap it. I didn't seal the wooden surfaces good enough and the result was a very hair mold and almost torn up prototype. I have been busy sealing the pieces this evening. I'll cut the first mold up so at least I can save on RTV.


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## rkapuaala (Jan 3, 2008)

Thought I would start showing some of my work on this project. 








This first picture shows the parts I have cut out for the molds. The melamine is for the bottom of the molds. It is 3/4 inch. I like using melamine because it is a lot flatter than plywood and I have a lot of scap left over that can't be used for anything else


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## rkapuaala (Jan 3, 2008)

I am masking the surface of the part that will come in to contact with clay. It has been my experience that removing clay from detailed surfaces is tedious and long. When I remove the first half of the mold, I will pull the clay off in one huge chunk and then peel the tape off revealing a clean surface. 
Note that the tape must be firmly adhered to the surface. To make help facilitate this, I put the parts in a vacuum chamber once the tape is on.
Sorry, but I took this images before I cleanly trimed the tape from the edges. Note the part to the left reveals some tape overhang. This must be cut flush to the edge if you want a clean edge on the mold.


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## rkapuaala (Jan 3, 2008)

This is a layup of the front end. I apologize that these shots are out of sync, but I sometimes forget to take pictures and so you will see various stages of the process, but on different parts. 
The first thing I do, not shown here, is to trace an outline of the part on the melamine. I apply the clay to the inside of the outline, then I squeeze if flat with another piece of melamine with wax paper on it. When I'm sure the surface of the clay is flat, I heat it up with a blow dryer so that it looks a little glazed, then I place the piece on the clay with the unmasked side up. 
I forgot to mention this most important part in the masking; always mask the least detailed side of the part. This makes masking much easier and metigates destortion to detailed parts that might occur after you gently press the part into the clay using a wooden straight edge. 
After the part has been pressed into the clay, I use a combination of dental tools and pallet knifes to trim the clay away from the part and the vents and sprus.


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## rkapuaala (Jan 3, 2008)

This is just a shot of the second half of the mold. I forgot to take pics of the first half. 
There are two steps for the first half. The first step of course is to pour the rtv into the mold, which also has two steps for me; one I mix the rtv and while its still in the mixing bowl, I extract all the air. That takes about 15 minutes. The second part is to pour it in the mold and then submit it to a vacuum for an additional 17 minutes or more depending on the amount and type of air bubbles I see on the surface of the RTV after the elapsed time. 
Once the RTV sets, I poor a backer straight into the unbroken mold right on top of the RTV. The backer makes sure the mold retains its original shape. Once the backer has harden (about 1 hour) I flip the mold over, break out two sides and remove the melamine, the clay and the masking tape. 
Sometimes the tape bleeds so you need a razor knife and some detal picks to clean up leaks. 
Once the part is cleaned I put the sides back on then I coat the first half of the mold with my solution of vasaline and paint thinner. I do 3 coats of this letting the solution dry before each and before finally pouring the second half of the mold.


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## rkapuaala (Jan 3, 2008)

This is a shot of the first two castings while still in the first part of the mold. If you look close you can see the backer. For these parts the backer is casting resin. I did this because the figure business has been slow and the resin is about to go. Resin does not last a long time on the shelfs and I bought a gallon expecting a lot of figure sales this summer. The economy went south and now I am left with using the resin before it goes south. Normally I would use plain old board resin because it is a lot cheaper. It important to note that when using the boat resin, do not, do not mix it too hot. 
Anyway what you are seeing in this image is what I refer to is my cleanout piece. This is usually discarded but this piece turned out pretty good, I will probably use it on my own 4-4-0. The cleanout piece does a couple of things. It removes the small smears of clay that are hard to get off the rtv and it shows me where the venting problems are so that I can cut them out with a razor knife. I had a couple of them on this part, nothing great big and you can probably spot them.


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## Pete Thornton (Jan 2, 2008)

Richard, I tried to email you via the 'send message' link, but got this:

undeliverable to xxxxx
Body of message generated response:
550 Error: Possible Spam peculiar Subject line

Maybe you could add MLS to your email contacts so it accepts messages?


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## rkapuaala (Jan 3, 2008)

Thanks Pete, but could you edit out my email address from your post. It makes that address vulnerable to phishing programs that scour web pages looking for email addresses to spam. I got your email through MLS and sent back a response, again thanks for the interest. As far as adding MLS, it is already on there. The problem looks to be with the subject line. If you send message me right here on mls I will be able to determine what words, or combinations of words got the email rejected.


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## rkapuaala (Jan 3, 2008)

Thanks Pete


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## rkapuaala (Jan 3, 2008)

Was cleaning up my shop area today and I came across this clean out piece. I thought this would be a perfect example of why you want to make sure you put the most detail side of the part up for the first pore. Its a poor image but if you look at the top door stop you can see evidence of a distortion. This occured because the detail of the door stop on the mold was too thin. Had I setup the part correctly with the door stop facing up for the first pour, then the stop would have had more backing and would not have warped. 
If you look at the windows you can see a lot of flash that is covering those window stops too. Again if I had poured this side first I could have avoided that too.


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## rkapuaala (Jan 3, 2008)

Oh,,, I had to remake this mold too. So far I've learned a couple of things on this project. REALY REALY seal wooden surfaces and make sure you put the most detailed side of a part up for the first pour.


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## East Broad Top (Dec 29, 2007)

Lesson #3 - If you're only doing two or three cabs, it's easier just to build each of the buggers from scratch.  

Seriously, thanks for the instructions. It's a fascinating process to watch. 

Later, 

K


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## rkapuaala (Jan 3, 2008)

I agree K, but I'm making more than 4 cabs


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## rkapuaala (Jan 3, 2008)

I poured my first piece for the roof today and assembled some of the cleanout pieces so I could check the fit on the Windows, Doors, and that tappered rail piece. 
Everything seems to fit ok with minimal filing as long as all the parts are trimmed well.


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## rkapuaala (Jan 3, 2008)

As you can see, I didn't calculate the amount of resin I would need to pour for the roof, so its kind of fragile because of the big air bubble running down the center.


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## rkapuaala (Jan 3, 2008)

All and all for clean out pieces, its not too bad. So I glued all the parts together except the roof and started fiting the doors and the windows. They fit just fine and I was able to use the vents on the doors for a hinge pin after drilling a hole in the sil and the top plate.


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## rkapuaala (Jan 3, 2008)

I just temporarily fitted the vents to the doors and windows. I need to fabricate the little tappered rail and then I can lay it up in the same pour as the windows and doors. Of course, I still need to add more vents and a pour tube.


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## rkapuaala (Jan 3, 2008)

Got some more shots of the mold making process this weekend when I made the mold for the windows, doors and that little corble thing that suports the cantilever on the roof. 
This is where I scribe around the parts so I know where to put the clay. After the clay is layed on the board. I take another flat piece of material and flatten it. Then I use a hair dryer to heat the surface till it looks glazed and set the pieces down and trim and smooth out the clay around the pieces and the vents. 








If everything goes right, the first half of the mold looks like this. Note that the only vents are the door hinge pins. I made impressions in the clay to show where they go. After the second part of the mold cured, I cut the vents in with an exacto knife. Seems to work better than putting actual vents in, but I had to make sure that I at least made impressions in the clay bed where the vents belonged so that this line was transfered to both halfs of the mold. 
That was the final mold and I have some more shots, but I'm gona finish assembling the test cab and I'll post some images later.


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## rkapuaala (Jan 3, 2008)

Took this image while I was waiting for the mold to set. It shows me installing the top rail for the window glides. This is just a piece of styrene 1/16 x 1/8 x 2 3/4 inches. It's a little loose so I don't have to worry about bending it. The windows already fit tightly so a bend will make it almost impossible to slide them open or closed. 
I guess I could get 1/64 piece or styrene or something and move the top rail out a little to allow for an easy glide, but I like the friction, it should keep the window from sliding back and forth when I pick the loco up to transport it.


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## rkapuaala (Jan 3, 2008)

Here is an image of all the castings. As you can see there is a lot of flash around the edges, but it is very thin and breaks off when rubbed. 
One thing that slows down production these is the need to wait for the resin to set up longer than normal. My shops not heated and the thermometer roams between 60 to 80 in the summer and 55 to 70 in the fall and most of the winter, at times it dips as low as 42 degrees (rare) and as high as 90 degrees (rare), which makes the cure time on resin variable. 
These castings have to stay in the mold so the resin is set enough so that it won't stretch, but plyable enough that the thin pieces don't snap. Tricky, when you have the temperature ranges I experience in my shop, but I'm sort of getting used to it.


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## rkapuaala (Jan 3, 2008)

Here are is an image of the parts cleaned and ready for assembly.


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## rkapuaala (Jan 3, 2008)

This is it, the test cab is fully assembled with doors and windows. All and all the project went smoothly. I had to re-make 2 molds out of 5 molds, but saved on rtv by cutting up the bad molds and filling the new molds with that. 
I also came to some conclusions, 
1. The hinge pins on the doors turned out to be another bad idea. The pins are only 3/64 dia and once the resin hardens it gets brittle so the pins broke. I did leverage that to increase the vent on the bottom of the door where the hinge pin was. 
2. Alumilite blue modling clay is the pits. For one, it is very granular compared to the other modeling clays I've used. It also takes a long time to melt and once its melted even longer to harden. Lastly the blue dye gets all over everything including my hands. For a week know, I've had hands that look like papa smerfs hands. 
3. Some molds require a little vacuum before pressure, some are better with just pressure. 
4. I need an injection mold machine  








THE END


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## Pete Thornton (Jan 2, 2008)

Richard, 
Talking about climates... Many locos in the freezing north of America have cab doors on the back wall. Is your front wall suitable to also become a back?


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## rkapuaala (Jan 3, 2008)

Pete, 
Thats a good point, but did the 4-4-0s have those back walls? I thought they had canvas tarps or something? The original cab had no back wall. I do not think the front wall would make a good back wall. For one it has the cut out for the boiler, for the other wouldn't you want doors that lead to the tender? 
I'm wondering if backwalls were something that was put on a cab once they became oil burners because, the wall would sure empede access to the coal or wood bin. 
Anyone have info on this question?


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## Rich Schiffman (Jan 2, 2008)

Richard,

I think some of the 4-4-0 and 2-6-0 locos had back walls, partial, but not completely closed in like the C series in Colorado. Just enough back to have a small window, much like the stock cab on those engines.


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## rkapuaala (Jan 3, 2008)

So,,, you mean like the two panels behind the seats on the stock bachmann 4-4-0?


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## Rich Schiffman (Jan 2, 2008)

Richard,

That sounds pretty standard to me. I am thinking about the NCNG 2-6-0 number 5. I seem to remember it had that type of cab. There is a drawing in the Nevada County Narrow Gauge book by Gerald Best. It was done by Herman Darr and shows a panel in the rear of the cab. By the way, your cab would make a super No. 5 on a Bachmann 2-6-0.


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## rkapuaala (Jan 3, 2008)

Does the no 5 have the back panel? Also, can anyone scan that image and post it here? I could get dimensions from it


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## Jeff Livingston (Jan 2, 2008)

Rick, 

I think it's time to remove the "Fail" portion of the topic heading. It's clearly obvious you'll finish, and in your usual outstanding style. The cab looks great and congratulations on your photo contest entry win. Now you can't change Lanikila! 

Jeff


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## rkapuaala (Jan 3, 2008)

Thanks Jeff, 
If I ever figure out how to edit the subject I'll do that  BTW, I got my computer fixed, and I can scan again. I'll put up some images of 98 either tonight or tomorrow early. 
As far as changing Lanakila, I'm building a Lanakila 2. I want to do her so that she looks more like a 1904 version just after converting to oil.


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## Rich Schiffman (Jan 2, 2008)

Richard, 

Send me an email and I will send the scanned drawing of NCNG No. 5. It is not great since it is a 2 page fold out, but you will see the cab rear in 2 versions. See email in signature block.


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## rkapuaala (Jan 3, 2008)

Sent


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## Rich Schiffman (Jan 2, 2008)

Richard, 

I received your email but all emails I have sent as a reply have bounced by your server. Help please. Thanks,


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## rkapuaala (Jan 3, 2008)

Rich, 
I recieved one of you emails. I checked my log and found that your client was being rejected. I got a lot of spam from that particular client and black listed it. I've removed it from the black list. BTW, could you email me in text mode. I work primarily in Linux and can't read the rich text or html email without saving it to a file and opening it up in a browser.


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## Pete Thornton (Jan 2, 2008)

Richard,

Obviously too warm in Hawaii for you guys to see cab backs, so I grabbed the camera and took a selection.

I think the canvas backs were used in desert climes to keep the dust and torrential rain out. Up in the NE, we have a problem with freezing cold. 

Here's the back of my latest Bachmann ten-wheeler, from the 'Summit Pass' set. My Sam's club loco has the same one.










Note the boiler continues all the way back (keeping the inside warm - nasty in mid-summer!) The poor fireman had to leave the cab to shovel coal. Guess opening the fire doors would give him somewhere to warm his hands!










Here's my Accucraft C-16 live steamer. Back cut away to let oversize fingers at the controls.










This is the Aristo/Delton C-16 (1/24th electric.) Same principle, slightly different details.


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## rkapuaala (Jan 3, 2008)

I see what you mean, except these all have extended boilers. What would the cab look like in back without an extended boiler. The mogul and the American did not have boilers that extended out to the back of the cab, so my question remains, how would the fireman get access to the tender without opening some very big doors in back? What did that look like? 
Richard


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## rkapuaala (Jan 3, 2008)

I just got a scan of the elevations for the Nevada County Narrow gauge mogul #5. The rear of the cabin shows that boiler section at the back of the cabs is completely open, and there are back panels with windows behind the engineers and the firemans seats. Nevada get pretty cold, but I'm not sure it gets is cold as where Petes from, so I'm wondering what the rear of the cab would have looked like in those areas. 
One thing I think, is the cabs didn't need to worry too much about heat, seeings how they were right next to a huge heater,,, more than likely they would have to worry about insulation from all that heat?


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## Semper Vaporo (Jan 2, 2008)

Engineers and Firemen were often "fried" on one side and "frozen solid" on the other. Cab side windows often were open when running (early engines had no glass in the opening anyway). When canvas curtains were hung across the back it was often only as an afterthought, not "standard equipment"; again, especially on early engines. Look at some of the "Camelback" engines where the Fireman had only a small roof over the back of the engine and no sides at all... just barely a place to stand while shoveling coal. The Engineer was crammed into the small space in the cab on the side of the boiler, often in direct contact with both the cab wall on one side and the boiler wrapper on the other at the same time. Employee "comfort" was not of great concern until about the latter half of the 'Steam Era".


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## rkapuaala (Jan 3, 2008)

It would seem a difficult thing to regulate the heat. If you close off the cab completely, even in the winter, it would be like being in a sauna. Is that why most of the cabs have those top vent doors? They look too small for roof access, and I imagine it would be easier to access the roof by climbing on top of the tender.


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## Pete Thornton (Jan 2, 2008)

Posted By rkapuaala on 10/22/2008 12:22 PM
It would seem a difficult thing to regulate the heat. If you close off the cab completely, even in the winter, it would be like being in a sauna. Is that why most of the cabs have those top vent doors? They look too small for roof access, and I imagine it would be easier to access the roof by climbing on top of the tender.


As far as I know, the roof hatches were for vent-ing not access.

I've looked around my shelves, but (as I thought) there are very few photos of locos taken from the rear 3/4 so you can see the back of the cab. Hilton's 'American Narrow Gauge Railroads" has several plans, including two locos with short fireboxes. Both show an open back with two side doors and a square opening in the center, similar to the photos of the B'mann and Aristo loco on the previous page. I'm guessing that, despite the short firebox only extending a small distance into the cab, the fireman still had to swing a shovel from the tender into the fire doors, so the back was left open in all cases.

There's an excellent photo of the back of the B'mann mogul in Jack Thompson's New #12 thread. I'll link it to here:










Richard - if you cut the doors off a front and scrapped the center section, you'll get this effect?


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## rkapuaala (Jan 3, 2008)

I think I'll plan on making a conversion kit based on the designs Rich sent me and this photo. Right now, though, I'm gona finish custom painting the cab that was ordered and then work on some instructions to send with the kit and post on my website. Thanks Everyone for all the great feedback, I've certainly learned a lot about cabs at least enough to know there is nothing simple about railroading.


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## rkapuaala (Jan 3, 2008)

Was just going to end this thread, but wanted to show an image with the test cab mounted. It is held in place by 6 - 00-90x hex head screws secured into the bottom of the cab. For more details on assembling check out My instructions page


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## Pete Thornton (Jan 2, 2008)

Posted By rkapuaala on 10/23/2008 1:34 PM

Was just going to end this thread, but wanted to show an image with the test cab mounted. It is held in place by 6 - 00-90x hex head screws secured into the bottom of the cab. For more details on assembling check out My instructions page


Richard,

I did find a photo of another Baldwin 4-6-0 on the EBT with just a pair of doors at the back - like the B'mann Mogul photo above. Could you offer a couple of extra front doors, for those of us who want to frame them in the back opening, please?

As you were too polite to provide the link to the kit, I had to go find it! Here's the kit Poe o honua Accessories Page.


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## rkapuaala (Jan 3, 2008)

Pete, 
The doors won't fit that area back there. Also, I tried it on my Annie and the cab is way too small. I'm going to do an Annie conversion sometime in the future. I was going to do number 64 that came with a wooden cab, so when I make that cab, I'll do some molds from it. The OR&L version was also open, but I'll cast a separte back door system for that cab too. I will be offering a back panel for the current cab in the near future as an upgrade or as parts to a different kit. 
As it is the resin castings are so much better than the styrene, I took the cab off Lanakila last night and mounted one of the cabs to her. I'm going to paint it today along with another one that someone else ordered. 
The fact is the castings need a lot of clean up though to fit right because the molds are rubber and seem to distort a little no matter what I do. They are still 20x faster than building a scratch cab, but just thought you would like to know how much work is involved, so check the link to the instruction page above.


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## paintjockey (Jan 3, 2008)

Just for the record, the 755 a Nickel Plate Road Berkshire has no back on the cab, only a canvas curtain. The berks were one of the most 'modern' high tech steamers.


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## rkapuaala (Jan 3, 2008)

Ok, I couldn't resist putting a new cab on Lanakila. I mounted this one from underneath as my instructions show. It feels a lot more solid than the styrene


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## Bruce Chandler (Jan 2, 2008)

Looks good. I guess the final vote was to "Finish".


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