# Dual chamber vs single chamber boiler smoke unit



## ChopperCharles (Jan 3, 2012)

So, I received my first dual-chamber smoke unit the other day. Pulled it apart, cleaned the wick in carb cleaner, rewound the nichrome wire with fewer coils, and put it all back together.

First thing I notice, the chuff noise from the dual chamber smoker is MUCH louder than from either of the two single chamber locos I have. 

However, the smoke output is significantly less, even with the same 35 ohms worth of nichrome coil wrapped around the wick. In fact, if I take the smoke units off, power them up and blow through the piston chamber, I get a nice big tall puff out of the single chamber, and more of a slow, short puff that never gets very high out of the stack. 

Is my dual chamber in need of further cleaning or service, or is that just how they are? I do like how much louder it is, that's for sure, but I was hoping for more smoke output, not less.

Charles.


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## flyernut (Oct 31, 2010)

Use less winds on the ni-chrome wire. The less turns, the more smoke, but the life is shorter.I use around 10 turns. Make sure the hole in the baffle plate is not clogged, or just make it a tad bigger.


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## ChopperCharles (Jan 3, 2012)

Which hole where? There are several holes. I think the problem is just not enough air flows through the old style. Maybe it's still plugged, I dunno.

charles.


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## flyernut (Oct 31, 2010)

There should only be 1 hole in the baffle plate.


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## ChopperCharles (Jan 3, 2012)

What is this baffle plate you speak of? The metal bit that's between the cylinder and the wick housing? There's also a hole in the cylinder and a hole in the wick housing. I don't know what you'd call all these parts.


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## lmcintyre (Mar 7, 2013)

Hi new to this site, found lots of good info.

I just rebuilt one of my AF smoke boxes and I am attaching some info that could help you. If this is same type that you have.

You have a thin baffle plate with one hole between the cyl and smoke chamber, then one hole in the box going into the smoke chamber where your wick is. these both need to be cleaned. (Be careful not to damage the thin baffle plate)

Also try putting a little petroleum jelly around the inside wall of the piston cylinder, (just a thin coating so it will not be pushed up into the cyl hole), it really helps to create a seal and provides greater air pressure during operation.


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## flyernut (Oct 31, 2010)

lmcintyre said:


> Hi new to this site, found lots of good info.
> 
> I just rebuilt one of my AF smoke boxes and I am attaching some info that could help you. If this is same type that you have.
> 
> ...


Exactly correct, and welcome!!


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## ChopperCharles (Jan 3, 2012)

I used axle grease, as it's made for high temp applications. I'll go back in and clean the holes... hopefully I don't mangle the nichrome wire getting it apart again. 

Charles.


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