# Suction Fan



## GigaPK (Jul 27, 2012)

I just got my first live steam engine that requires a suction fan. Which one do I get as it is a very small locomotive (a gauge 1 b4) I also cannot contact the people at aster if that is the best supplier of suction fans.


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## Pete Thornton (Jan 2, 2008)

GigaPK said:


> I just got my first live steam engine that requires a suction fan. Which one do I get as it is a very small locomotive (a gauge 1 b4) I also cannot contact the people at aster if that is the best supplier of suction fans.


Gigapk,
Are you sure it requires a fan? The current supplier of the B4 is Accucraft, and it is gas (butane) fired. It does not need a suction fan.

There is really only one type - the Aster version, although I've seen homemade variants. Curious why you cannot contact Aster - or is it just a xmas thing? 
Jim Pitts at Southern State Live Steam usually has all the answers and accessories:
http://www.southernsteamtrains.com/accessories.htm. Aster's website says they have the fans in stock.


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## Chris Scott (Jan 2, 2008)

If it's alcohol or coal fuled and you need a fan, Accucraft sells a fan, so does Jason, The Train Department (which I'd guess is the Accucraft fan.) Cole's Power Models; PMI Research; Bruce's Model Engineering, pretty much they're sources all over the place. I even think Small Parts sells one. The Aster you just pay a lot more.


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## GigaPK (Jul 27, 2012)

It's the Barrett steam model version


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## GigaPK (Jul 27, 2012)

Is there a best suction fan to use


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## Phippsburg Eric (Jan 10, 2008)

My Accucraftwornks fine! So does my home made one...they are probably not all that finicky.

Happy new year!


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## Kovacjr (Jan 2, 2008)

If you are coal fired the Accucraft has more draft. The Aster one works juts fine and they offer a 2 and 3 cell version though you can add a 3rd cell on your own too. I have both the aster and Accucraft ones. They are all built the same. Really preference. Being that Accucraft has no stock of the fan that leaves the Aster one your current option. How sure what email or phone number you had for Hans but current ones are listed on the asterhobbyusa.com site


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## Chris Scott (Jan 2, 2008)

Finally found a picture of using a airbrush compressor as a suction fan - actually I think the pump is blowing creating draft up the stack. Tony Dixon and Jim McDavid. On the first go-round of this thread I thought about describing this versus having a picture and obviously a picture works where a description (at least mine) would not.


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## Semper Vaporo (Jan 2, 2008)

That pipe and air-pump look a lot like what I use. Mine is made of two brass tubes. One is just slightly smaller than the inside diameter of the smokestack and about 2 to 3 inches long. The other is 1/8 inch in diameter and about 2 inches long.

Drill a small hole (1/16 inch) in just one wall of the small tube, about 1/2 to 3/4 inch from one end.

Drill a 1/8 inch hole through the larger tube about 1/2 to 3/4 inch from one end, all the way through so you can insert the smaller tube crossways (in the diameter) through the larger tube. Lengths are not terribly critical, and diameters are not either, except the larger tube diameter should be good easy slip fit for the stack.

Insert the small tube into the holes in the larger tube and be sure the small hole in the small tube is centered in the larger tube and is aimed toward the longer end. Crimp or plug one end of the small tube and solder it shut for no air leaks. Also solder the small tube in place so there are no leaks between it and the larger tube walls (be sure the small hole is centered and visible from the long end of the larger tube). Soft solder will do since the exhaust temps will not be enough to cause a problem and there will be no pressure applied to the joints.

To use this device, attach an air pump to the open end of the small tube and insert the larger tube into the stack so that air that will be pumped into the small tube will be blown up the larger tube. The small tube protruding outside of the larger tube will prevent the device from falling into the smokebox.

The escaping air will be at a greater velocity than the air in the larger tube and will thus be at a lower pressure. This relative vacuum will draw air from below the small tube (from inside the smokebox) and expel it out the top... the relative vacuum in the smokebox will thus draw air through the flues from the firebox as draft for the fire.

I happen to use a battery powered tire pump for mine and it is quite noisy, but I think that a small aquarium pump would work just as well if you have a power source for it. (Even a hand operated bicycle pump would work if you have the stamina to work it for the several minutes required to get enough steam to run the internal blower to provide draft.)

The attached drawing shows the device.


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## cocobear1313 (Apr 27, 2012)

Rube would be pleased Seems like a lot of kit compared to a fan.


Dave


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## David Leech (Dec 9, 2008)

In the 'good old days', I have seen a bicycle pump attached to the tender pump which would pressurise the boiler allowing the blower to be opened to create the draft.
When steam was raised, it was removed, water added to the tender and all was 'normal'.
No batteries to worry about, or finding somewhere to plug your air pump to!
You just have to remember to bring your bicycle with you to the steamup!
All the best,
David Leech, Delta, Canada


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## Semper Vaporo (Jan 2, 2008)

cocobear1313 said:


> Rube would be pleased Seems like a lot of kit compared to a fan.
> 
> 
> Dave


I absolutely agree, except the whole thing cost me about $3 because I already had the tire pump. A good fan, "designed for the purpose" is a bit over $100.

I also have used a computer CPU fan. Found one at a junk shop for $1 and folded up a cube of sheet brass ($5) that fit the edges of the fan, drilled a hole in the bottom of the cube and soldered in a short length of brass tube that fit in my loco's stack. Ran the fan off of 8 AAA batteries. Worked great for about 5 years. Then I noticed a "ticking" sound and found that the heat and spinning had cause the plastic fan blades to extrude a small finger from the outer trailing edge and one was now big enough to be hitting the sides of the cube. I bought a replacement fan from Radio Shack (same part number) but it had been redesigned such that the motor was more exposed than the original one and it lasted through about 2 steam-ups and the motor circuit board was too wet and oily to work anymore. I then tried a "J" tube inserted down the stack and it was too hard to keep aligned so I came up with the "Rube Goldberg" design above.

I also tried using a 5 gallon air pig that I would charge up to about 80 PSI at the gas station. I connected it to the boiler in place of the tender water supply and used the internal blower to provide draft from the air flowing through the boiler... just had to be sure to open the blower and close the throttle before I open the valve on the air pig so I didn't over-pressurize the boiler or have the engine take off without me! With the blower valve open all the way and the air pig valve barely open I got plenty of draft without the pressure gauge showing anything. I could get two operating sessions out of one charge in the air pig.

Yes, the battery operated fan, designed for this purpose is probably the best solution, but it is also probably the most expensive solution if you don't have to buy a battery powered air pump to operate my "Rube Goldberg" design.

BTW; Using a hand operated bicycle tire pump is not really all that difficult. It does not require rapid hard pumping, just slow and easy works just fine, whether using my Rube Goldberg design or putting the air through the boiler to use the internal blower.

It is all a matter of economics and personal convenience.


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## artgibson (Jan 2, 2008)

*With what we pay for engines*

With what we pay for the coal fired and alcohol fired engines, what iis 100.00 dollors plus the convenience of 
sitting the suction fan on the stack and letting her rip. I cannot see standing there with a bicycle pump when there are other things to do in preparation to run the engine.
I builf one of the devices to attach to stack and using a battery operated pump and it did nothing but glow the ashes up the stack,


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## Semper Vaporo (Jan 2, 2008)

gibs035 said:


> With what we pay for the coal fired and alcohol fired engines, what iis 100.00 dollors plus the convenience of
> sitting the suction fan on the stack and letting her rip. I cannot see standing there with a bicycle pump when there are other things to do in preparation to run the engine.
> I builf one of the devices to attach to stack and using a battery operated pump and it did nothing but glow the ashes up the stack,


Again, I agree, compared to the $4,000 I paid for my Aster Mike, that $100 is a mere pittance... but considering that it took two year's of tax refunds and two credit cards to get that lovely loco, that $100 would have meant the difference between having the loco and just being a dreamer.

Is my "Rube Goldberg" a bit of a "kit" to carry to the track... yep, along with the box of oil bottles (steam oil and general use), alcohol fuel, distilled water, extra wick material and tweezers & scissors (for trimming wicks if necessary, but have never been used) syringes (for sucking oil out of the Roscoe Displacement oiler, and for transferring fresh oil into it and for transferring alcohol to the fuel tank and another for transferring water to the boiler and tender tank), a bottle to collect the dregs from the Displacement oiler (no need to spew it on the ground where someone might step in it and track into my house), wrenches, screwdrivers, pliers, funnels, rags, camera, radio control transmitter, and whatever else has collected in that box, along with a box of randomly acquired rolling stock so the loco can have something to pull... well... that "kit" is a mere pittance itself, but it works very well, and the cost was so low that I managed to buy TWO boxcars. And with the air pump (which I already had so there was not cost associated with the hobby) I don't need to be standing there pumping on a bicycle tire pump, but for those that are still at the "OH MY GOD! THIS IS AN EXPENSIVE HOBBY!" state, it is a way to get the engine fired up and enjoy the pleasure of watching it run, with a slightly lower initial cost.


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## cocobear1313 (Apr 27, 2012)

Semper Vaporo, Sorry I offended you with "Rube Goldberg". The deal was just amusing to me. I went to much greater lengths to save a buck in my other hobby of RC air planes.

Dave


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## Nick Jr (Jan 2, 2008)

I can also think of several things I've gone way over the edge of being practical to utilize a few scraps of left over things I have laying around and saving a few pennies. Time and ingenuity spent is part of the hobby. IMHO


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## Semper Vaporo (Jan 2, 2008)

cocobear1313 said:


> Semper Vaporo, Sorry I offended you with "Rube Goldberg". The deal was just amusing to me. I went to much greater lengths to save a buck in my other hobby of RC air planes.
> 
> Dave


Absolutely no offense taken. You are absolutely right. And if it didn't work, I wouldn't use it! But since it does... I have more money to spend on Victorian garb designer dolls instead... err... I mean, I buy rolling stock.


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## rwjenkins (Jan 2, 2008)

I have an Accucraft fan, it sucks. (Of course, in this context that's a good thing!) 

I use the battery fan for my alcohol-fired gauge one engine. For my 3 1/2" gauge coal-fired ride-on engine, my nearest live steam club track has compressed air lines to all of the steam up bays, so I use a J-tube there. It's basically what it sounds like, a length of small-diameter brass or copper tube, with a 180-degree 'J' bend at one end, and a hose attached to the other end to connect to the air supply. The J end goes down the stack so the air blows back up the stack. Mine has a 90-degree bend at the other end that rests on the rim of the stack and helps to keep it in position. A battery suction fan is less hassle than hauling out an air compressor and hooking everything up, but if you're eager to get steaming and you have an air compressor and you have some metal tube and silicone hose lying around, a J tube is a simple, inexpensive way to get going while you're waiting for a new battery fan to arrive.


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## Steve Shyvers (Jan 2, 2008)

I rigged up a 3-gallon garden sprayer with an air regulator and pressure gauge when I was building and debugging my first forced-draft alcohol-burning locomotive. It worked fine to drive a j-tube auxilliary blower. Got lots of exercise while raising steam. Then when I built a coal-fired loco I bought an Accucraft stack blower to make it easier to tend the coal fire.


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