COS modifications.

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Original poster
Jan 26, 2014
So I've been working on a cheap offset.  I got it for about 100$ off amazon, and figured I could find a way to make it a reverse flow, and down the road, buy or a build something with better steel.  Here's what i've been working with.

Not the greatest, not the worst.  

I burned some coal through it, and it had leaks everywhere.  I then got rope gasket for the main chamber, and used a high heat cement around every opening to contain the rest of the leaks.

(also added in the board and hooks.  just drilled holes in the metal, then screwed in from the bottom.  easy peasy)

This is when I started to think of how to make it work like a reverse flow system.  And got creative.  

using aluminum dryer pipe, and a sheet of flat aluminum, i made a prototype.  It fits snugly into the chamber, with a cut out for the pipe.  The final version will be cut from steel by a local machine shop.

this is the interior of the smoker

what you can't see is that I also extended the chimney down to grate level.

Now, the question, did it work?

Yes!  The firebox was leaking air like crazy still, so I put a brick on there to help the box seal.  That will now be a defacto piece of the smoker.

and does the smoke fill the entire chamber? 

it appears so.  I tossed in the broken pizza stone as I thought it might help with ambient heat.  and the brick is in there as a way to keep the baffle tight against the wall.  When the final piece gets made, it will be fully secured and sealed, so no brick will be needed.  

I'm still working on a way to make it electric AND charcoal, but right now, I think I've done well.  Now if I can just figure out how to work out a drip pan.....
Question ?   does the smoke/heat go from the fire box into the dryer hose, down the hose and out the open end ? If so you are going to have a problem with heat, Not enough. A RF smoker's heat and smoke enter the cook chamber from the fire box through an opening sized according to CC size. then travels under the RF plate to the opposite end of the cook chamber where it then exits through the opening left between the RF plate and end of the cook chamber, the smoke/heat then travels back across your grate/meat and exits through the smoke stack. The stack is on the same end as the fire box, hope this helps. You can convert you smoker to an RF, but you will need an RF plate and relocate your stack.

Doing a dry run now, to see how heat is contained. Pretty well as of right now, but time will tell.  I know that this isn't a true reverse flow sytem, but working on a tight budget, I think it's something that might make do.  Will definitely keep what you said in mind though.  All in all, I have ten dollars in this hair brained idea, so at least worth checking out.
Liam, morning and welcome...... Well...... It is obvious you are dedicated to "make stuff work" to get that "dearly sought after" smoky flavor in your food.... You fit right in.....

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