First time Building a RF combo smoker

Vaughan · Post by **Vaughan** » April 13th, 2016, 3:19 am

Hi Guys and Gals,

I am currently building a RF smoker and have a couple of questions, I have tried to search for the info I need but don't seem to be able to find the exact answers I am looking for. So hear goes

1. I am adding a cold smoke chamber to the top of the CC and am not to sure how big to make the exhaust from the CC to the cold smoke chamber, ie smae as exhaust size, same as throat size or other ?

2. do I add the volume of the cold smoke chamber to the CC chamber to calculate FB, throat size and chimney volume

3. am I better to have just a single hole into the cold smoke chamber or several smaller holes to make up the required area

4. when being used as a RF smoker the chamber above the FB becomes the warmer, I presume I will need to make vents in this as it will become quite hot rather than just warm, am I better to put vents into the chamber to release heat or add a further plate on top of the water bath to reduce heat (or maybe both)

Sorry if these are stupid q's but am getting a bit frustrated as I dont want to continue with my build until I am sure I'm getting this stuff right

Cheers to all

Oh have done a quick pic on Sketchup to kind of show layout ect, excuse how rough it is as I have not used it before

Post by **Pete Mazz** » April 13th, 2016, 4:25 am

Welcome!

Interesting concept! Trying to make one unit an all-in-one is going to be an experiment. Why not have the WC function as a cold smoker instead? I think if you insulate the FB and have the necessary vents it might work. How about for a grill, have a lift out charcoal pan that sits on the BP?

The Czar · Post by **The Czar** » April 13th, 2016, 5:45 am

Welcome aboard

mp4 · Post by **mp4** » April 13th, 2016, 6:03 am

I like the design - you could call it a double reverse smoker.

I would ditto Pete's comments about using the warming cabinet for the cold smoker but I'm more interested in seeing your design in action!

Squiggle · Post by **Squiggle** » April 13th, 2016, 6:31 am

Yep, totally agree. You have to really control the air intake carefully with cold smoking & the further away from the fire you have the smoke chamber the better it will be for cold smoking. I have found that either wood chips or sawdust works the best for cold smoking, 1 cause you get less heat from the smouldering wood & 2 you get a lot more smoke for the size of the fire. As long as you don't let it catch fire you'll be right.

forty_creek · Post by **forty_creek** » April 13th, 2016, 12:23 pm

Welcome! I can't help with cold smoke never tried. But I do think you will need fresh air vents to release the radiant heat in WC. I was advised to do so from this site. Glad I did.

Drankin, Smokin and Dreamin

Sent from my iPhone using Tapatalk

Post by **Pete Mazz** » April 13th, 2016, 4:33 pm

I use a small electric burner and some wood chunks in a cast iron skillet to cold smoke.

Vaughan · Post by **Vaughan** » April 14th, 2016, 5:10 am

Hi guys, thanks for the input. I will continue with the research and please any ideas and comments are most welcome and appreciated.

Vaughan · Post by **Vaughan** » April 14th, 2016, 5:22 am

Pete Mazz wrote:Welcome!

Interesting concept! Trying to make one unit an all-in-one is going to be an experiment. Why not have the WC function as a cold smoker instead? I think if you insulate the FB and have the necessary vents it might work. How about for a grill, have a lift out charcoal pan that sits on the BP?

Hmmm, I like the idea of a lift out charcoal pan for the grill. As for the WC being used or the cold smoker I was trying to have the path to the cold smoker as long as possible to allow the smoke to cool as much as possible.

Post by **Rodcrafter** » April 15th, 2016, 6:00 am

I typed this reply the other day but it got lost in the posting process, so here it is again.

Making memories.

Post by **Rodcrafter** » April 15th, 2016, 8:09 am

Welcome to the crew!

1. I would say don't use the exhaust stack from the main CC as the intake for the cold CC. Follow the specs of the pit calc. Add a second stack but off of the warmer cabinet instead. This will not mess with the air flow.

2. No it won't effect the CC doing it this way

3. In my opinion 1 opening into the cold cc with an damper on it so you can regulate it. Also the same size exhaust opening.

4. I love what I did to mine, I welded the top on the fire box then 2" of insulation, then another plate welded in as the bottom of the WC. I used a piece of 6" square tubing between the 2 plates with a damper to control the air flow. I can close it and it doesn't really even get hot or open it and cook in it. Or of course I can turn it down to use as an warmer.

As for the water bath, I don't use one but I do have a drip pan that looks like a water bath. It keeps direct heat from coming straight up and keeps the bottom of the WC clean.

Making memories.

Vaughan · Post by **Vaughan** » April 18th, 2016, 2:07 am

hi guys, another question regarding fire box insulation
I have allowed room in my FB to add a "fire brick" base and also have space to add insulation to all sides and the FB door. Has anyone used Perlite concrete http://www.perlite.co.nz/perlite/concrete/ (cast into tiles to line a fire box) am toying with this as an option for insulation as I can cast the appropriate shape easily and make replacement FB tile as required.

Cheers

Vaughan · Post by **Vaughan** » April 18th, 2016, 2:16 am

Rodcrafter wrote:Welcome to the crew!

1. I would say don't use the exhaust stack from the main CC as the intake for the cold CC. Follow the specs of the pit calc. Add a second stack but off of the warmer cabinet instead. This will not mess with the air flow.

2. No it won't effect the CC doing it this way

3. In my opinion 1 opening into the cold cc with an damper on it so you can regulate it. Also the same size exhaust opening.

4. I love what I did to mine, I welded the top on the fire box then 2" of insulation, then another plate welded in as the bottom of the WC. I used a piece of 6" square tubing between the 2 plates with a damper to control the air flow. I can close it and it doesn't really even get hot or open it and cook in it. Or of course I can turn it down to use as an warmer.

As for the water bath, I don't use one but I do have a drip pan that looks like a water bath. It keeps direct heat from coming straight up and keeps the bottom of the WC clean.

Making memories.

Cheers Rod,
I will take on board your suggestions and see how we go. I have done all of my calculations using the Pit Calculator and this has been invaluable.
Just to Clarify the waterbath plate is for cooking a "Hangi" with, this is a native New Zealand style of cooking where all of the food (meat and Veg) is cooked at the same time in the CC above the FB, it is a mixture of steaming and direct heat cooking where the fat from the meat drops down onto the center of the cooking plate and burns giving the food quite a unique flavor. The food cooks in approx 3.5 to 4 hours.

Vaughan · Post by **Vaughan** » April 18th, 2016, 2:26 am

update on what I have so far

Squiggle · Post by **Squiggle** » April 18th, 2016, 5:27 am

mp4 · Post by **mp4** » April 18th, 2016, 5:41 am

You're off and running - looks great!

Sent from my SAMSUNG-SM-G870A using Tapatalk

Post by **Rodcrafter** » April 18th, 2016, 7:27 am

That looks nice!

Elmacho · Post by **Elmacho** » April 18th, 2016, 10:19 am

Sent from my iPhone using Tapatalk

forty_creek · Post by **forty_creek** » April 18th, 2016, 1:03 pm

Strong Work V!

Drankin, Smokin and Dreamin

Sent from my iPhone using Tapatalk

Post by **Big T** » April 18th, 2016, 11:00 pm

Vaughan · Post by **Vaughan** » May 1st, 2016, 12:39 am

Hi Guys,

Heres an update on my progress so far. Am almost there....

Squiggle · Post by **Squiggle** » May 1st, 2016, 2:28 am

Very nice work dude, well done!

Post by **Pete Mazz** » May 1st, 2016, 3:31 am

Interesting!

What's with the vice on the stack? Seems like it would be an expensive damper....

mp4 · Post by **mp4** » May 1st, 2016, 3:49 pm

You are doing some very nice work - I love the arched firebox door!

Sent from my SAMSUNG-SM-G870A using Tapatalk

Post by **Big T** » May 1st, 2016, 10:26 pm

SmokerBuilder.com