Draft flow/top vent calculations...

[daveomak]

Very clean installation... you did good...

 

[indaswamp]

Thanks Dave. I'm smoking some chickens today to see how the larger vents workout and to start re-seasoning the bare spots in the smokehouse.

 

[indaswamp]

New vents worked great today smoking chickens...

Smoked with Apple and Hockory wood pellets and dust @275* for about 4 hours till leg temp reached 170*.

 

[daveomak]

Looks like something worked for you today.... awesome... Dave

 

[indaswamp]

So Dave, I've been thinking about that baffle. I'll give you the parameters I'm playing with...

Inside wall to wall in the smokehouse is 28.5" wide X 30" deep. I'm leaning towards 3/16" aluminum plate for the baffle because it's what I have access to. Very easy to clean, I'll weld a handle on the front to make it easy to pull out. My question is on drilling the holes. How small? How spread out? I was thinking maybe (1) 3/8" hole every sq. inch. That would give me about 650 holes, right at 75cu.in. of space for the smoke and heat to travel through. The smokehouse interior is 68" tall and roughly 36 cu. ft. volume.

Is 75 cubic inches enough flow through for heat and smoke? Do you think 3/8" holes are big enough? I use a 15" cast iron pan as a diffuser/wood pan on the propane burner, should I drill small holes through the plate directly above the ring of this pan?

The plate will be roughly 10" above the burner and 6" above the CI pan....

Or, should I drill larger holes on 1.5" or 2" spacing????

 

[daveomak]

Holes in the plate idea is something you will have to experiment with... size, spacing etc... All of the variables are based in physics... air flow, temperature, viscosity, pressure... Then there's the thermal mass issue.. Aluminum absorbs BTU's rapidly and gives them up rapidly... and it burns... it's one monster of a mess once the aluminum catches fire.. been there, done that.. never thought it would happen... evidently the fat from salmon burns hot enough to torch 3/16" angle aluminum.. Rocks, slow on the BTU up take and slow on the discharge... or what ever term fits... I'm kind of a simple guy.... If the rocks work, why change them..

 

[indaswamp]

Dave,
I think I have the answer. That 'Ah ha' moment...
I have some left over hardi board from the build. I will cut a piece big enough to use as a baffle... it's 1/4" thick and will perform nicely. Great thermal mass too. I'll need to play with the hole sizes though.

 

[Gwanger]

I preparation for smoking 150lbs. of venison sausage in the next few days, I decided to try and cut the BTU's in half on the burner. I wanted something temporary as a test, this is what I came up with...

4D nails cut down and inserted in the burner holes...
View attachment 353586

View attachment 353585

Took about 5 minutes using plyers to snip them. Inserted in the outer ring of jets..

View attachment 353587
View attachment 353588

Been down with the flu for the last 3 weeks...finally feeling better. When I catch up and get some time I'm going to install my Tejas burner with external venturi. This ought to suffice until then.

Indiaswamp, nice looking sausage, Looking into mods that you made to your LP burner, when you closed half of the holes with 16 pny nails that you shortened, did you have to pound them into the burner or just a tight friction fit.Don't want to destroy my burner. I am a sausage maker myself and would love to be able to get my LP smoker to 100 deg. for the lowest temp.

 

[indaswamp]

Friction fit. The weight of the nail is enough to keep it in place against low pressure propane. How many cubic ft. is your smokehouse?

 

[Gwanger]

Friction fit. The weight of the nail is enough to keep it in place against low pressure propane. How many cubic ft. is your smokehouse?

Never measured the smoke chamber but it is the double door Masterbuilt LP smoker and have had problems with too much heat even for smoking meat 285 deg. want to be able to smoke my sausage and fish not able to do at these temps.Interested in your mods that you made. Great looking sausage, Im jealous.

 

[indaswamp]

Measure the width, depth, and height of your cooking chamber in inches. Divide by 12 to convert to decimal feet. Multiply those numbers together and that is the cubic square feet of your smokehouse. Depending on how much space you have, will determine roughly how many BTU's you need. I do not know what the burner for you MES looks like; nails may not work. Might need to use screws like Dave posted.

And thanks for the compliment. I love making sausage, been doing it for a long time. Finally build a smokehouse large enough so I can make big batches for friends and family. I'm having fun with it....

 

[indaswamp]

In trying to look up the specs. for your unit, I found this:


Did you ever try this? Did you still get blow outs?

 

[Gwanger]

In trying to look up the specs. for your unit, I found this:


Did you ever try this? Did you still get blow outs?

Indaswamp, that looks like my smoker,will try soon, need to get lp, need it for my beer making and LP smoker still in 30'3 here. Haven't used smoker in over a year bc I was frustrated with not being able to control temps, you have helped more than I can say. thnx, anxious to try now!!!

 

[indaswamp]

Take some measurements and I can help you better...

 

[Gwanger]

Take some measurements and I can help you better...

I just measured, 24 in.h,16 in.w x 14 in.d

 

[indaswamp]

You have 3.11cubic feet in your smoke chamber. Looking @ the specs. I see your MES has a 15,400 BTU low pressure burner. I doubt you will need that many BTU's to run @ temps. under 170*. You may need to block off some jets if you still get blowouts running the burner on low flame. I do not know how the burner is made, might need to block holes with screws.

 

[Gwanger]

You have 3.11cubic feet in your smoke chamber. Looking @ the specs. I see your MES has a 15,400 BTU low pressure burner. I doubt you will need that many BTU's to run @ temps. under 170*. You may need to block off some jets if you still get blowouts running the burner on low flame. I do not know how the burner is made, might need to block holes with screws.

Indaswamp, thnx for all legwork you have done and finding the video on running the smoker and finding the temp adjustment to get lower temps. The temps here tday were in the 30's still,waiting for spring to be sprung.Thnx again,Do you ever smoke any Gators? Will try to lower temps like shown on video b4 I start plugging holes in burner.Since I am a retired carpenter I have plenty of screws and nails to plug the jets.

 

[indaswamp]

Never smoked gator. Would be very tough I would reckon.

 

[indaswamp]

Hey Gwanger...
Turn your burner on and count how many individual propane jets it has. Then take 15,400 and divide it by that number. Now you know how many BTU's you are reducing with each one you cover with a screw. This is how you dial the heat in. I recommend spreading them out, don't bunch them up all on one side of the burner or you will get uneven heat and hot spots in your smokehouse.

 

[daveomak]

The jets need to be close enough together to light one another... Not like lighting 70 birthdays candles..