Modding DynaGlo Vertical

[jmtyndall]

Look, it's nothing compared to what you all have, but a couple years ago my wife bought me a DynaGlo 36" vertical smoker because I wanted to try out smoking some meats. A couple months later I discovered this website and discovered the offset models are more popular, but no reason to throw out what you got, right? Being a bit of a tinkerer I decided to do some mods to improve the smoker.

Here's a stock photo of how it looked when I got it:

Per some reading I learned that I needed to do a burn-in, which was the perfect opportunity to learn how all the vents work. Well I quickly discovered that lighting it per the instruction manual with all the vents open spiked my temps over 600 degrees! Well that's no good for smoking, but luckily didn't warp the cabinet. During that run I discovered a myriad of smoke leaks, so I bought some high-temp silicone sealant and some LavaLock gasket material and sealed the doors. Finally, drilled a couple holes with grommets to get temp-probes in and out.

And that's pretty much how I've been using it since then. It's always been a bit of a hassle, but I got the process down so that I put about 3/4 box of unlit charcoal in the basket, add about 5 lit coals with the dampers wide open. Once I hit 180F I close the damper on one side fully, and the other one I close about 75% and for the most part I end up in the 225-250F range. I've smoked a turkey the last couple of years at 350, and even to hit that temp I've only needed to have one vent less than halfway open.

Being summer time, and smoking season, I've been around my smoker a lot recently and started noticing that even though I sealed the doors and weld seams, I still have some air leaks. First of all, there's a "grease drain" at the bottom of the box that's simple a 1" wide-open hole. Secondly, when the dampers are fully closed there's actually a 1/16" light gap that can be seen. Doing some quick math I'm estimating that I have just over 3" of open intake area even when my dampers are fully closed! And the chimney doesn't fully close either. So when I'm done smoking, I just end up letting all my charcoal burn to ash. Not very efficient when I'm aiming to do a short smoke like salmon or tri-tip!

So, I've come up with a small list of mods to do.
1) My firebox area is too small to fit the LavaLock minion method charcoal basket or the maze bars. It is just big enough to fit a couple of fire bricks. So I'll grab two of those to create a charcoal maze. Hopefully this will better control how many lit coals I have without having an entire basket go up in a 600 degree raging inferno.
2) With all the vents fully open, this smoker has over 20" of intake area. I did some research into UDS smokers as they seem more closely related to what I have than an offset. Most of those people are using 1-2" of free intake area and easily hit their required smoking temps. So I'm going to buy some 16 ga steel to seal off one of the air intakes (since I only ever use one of the 2 anyways). While I'm at it, I'll use a 3/4" nipple to seal the grease drain hole.
3) Since I want to be able to completely shut down the vents to snuff the fire when I'm done cooking, I'll actually be using more of that 16 ga steel to cover the intake vent that I've been using. Then I'll cut in a LavaLock pinwheel damper to control intake airflow. On the fence between putting in a 4" damper or a 6" damper. The 4" is more than double the area the UDS guys use, but slightly less than I think I usually use. 6" is huge and I'm trying to get away from cooking with the vents nearly fully closed.
4) Going to upgrade from the stock exhaust vent to a 2" pipe with teardrop damper. This will give me the ability to completely shut off the smoker and hopefully save any leftover charcoal after the smoke.

 

[JC in GB]

Sounds like you are doing all the necessary mods to the Dyna-Glo. I had a Dyna-glo offset and had the opposite issue that you are having. It was difficult to keep my temp up where I needed them. No way I could run that at 300. I had leaks in the seams and used high temp food grade silicon RTV to seal them. Being used, you would have to clean the metal well. I got many good smokes out of my Dyna-glo and I learned what I liked and didn't like in a smoker and it didn't cost me much.

 

[jmtyndall]

I think the air leaks manifest as different problems between the offset and the vertical.Thinking of the air path in the smoker starting at the fire box inlet and ending at the chimney, once the chimney starts to establish a draft you want the air to come into the fire box to burn the charcoal. On the offset, the air leaks happen mostly downstream of the fire-box so any leak is doing two things; 1) preventing air to the charcoal basket, 2) inducing cold air to the cook chamber lowering your average temp. The vertical that I have has no seams between the cook chamber and the fire box, so all the air leaks are happening at the very bottom and fresh air is drawn across the charcoal speeding up combustion and increasing my temps.

At least that's how I think it's all happening. Anyways, I sealed up all the weld seams after my first smoke. Don't see any signs of air or smoke leaks there or from the door.

Here's a pic of the door gaskets, well used. You can also see the temperature probes hanging into the cook chamber.


Last night I stopped at Home Depot, they didn't have the sheet metal I wanted, but I was able to pick up a couple fire bricks and a 3/4" pipe for the grease drain. Pics below. Theres about a 2.5" path snaking around the fire box. Hope that's wide enough. I can always pull out one of the bricks or try to get some metal bars custom made. You can see height-wise the bricks just barely clear the chip tray.

While I was at it I snapped a couple pics of the intake and exhaust openings in the "fully closed" position. These gaps are what we aim to fix here. Parts for these two mods should be coming soon. The three slivers of light you see on the intake are actually 6 slivers per damper because you can see light either direction. And then there's two of the dampers. So there's actually a fair amount of leakage area there.

 

[JC in GB]

Looks like you got this figured out. If I ever get another Dyna Glo it will be a vertical.

 

[fivetricks]

Seeing all this lets me know my next unit will be a vertical. Id be curious as to what you have into this financially and the results you realize once it's all done.

 

[jmtyndall]

Thanks guys. I'll try to add costs to things from here on. Now that you mention it, I'm curious too.

The smoker itself was around $150. Lavalock Nomex door gasket about $15, and the silicone sealer for the seams was another $10 or so. For the grease drain I used a 3/4" hex bushing, a 3/4" pipe cap, and a pack of conduit nuts from Home Depot for about $7 total. Fit was a little loose so I had to add an O-ring I had around the house, but I can't imagine it would cost more than a couple bucks. 2 fire bricks cost me $3.50 each. All in I think it would cost me $200 to duplicate where I'm at right now.

I'll track prices as I buy things for other mods. Currently shopping for sheet metal, paint and hardware for my blank-off plates. Original intent was to use 1/4-20 bolts for my blank-off plates, but they're priced at $1.50 per pair for stainless bolts not including the nuts. I'm planning on using 2 dozen and I'm not really interested in spending a fortune on hardware. I'll look at smaller hardware tonight

 

[jmtyndall]

Made a bit of progress tonight. Bought my steel plate and hardware, also needed a blade for my jigsaw to get a smooth cut. Got all this for $30. While we're discussing hardware, I discovered that 8-32 screws are sold in 12 round packs for about $2.50 each. Going any bigger in screw size and the packs drop to 6 screws for the same price. That's what drove my hardware size selection.


Measured and rigged something up to try and get a nice straight cut on the plate. Thankfully, this isn't for aerospace, so "straight enough" cuts with a jigsaw will do. Ended up with two roughly 8"x10" plates. 16ga is thicker than I expected, but 22ga felt floppy in the store. This stuff will probably be tough to cut my vent into, but I won't have to worry much about bending.


Next i measured out some screw holes and had what I thought would be a brilliant idea. See, if I clamp the plates together, I only drill half the holes, and they'll be symmetrical. Turns out...I was wrong. But again, we're not building airplanes! Even drilling in 2 steps this was a bit of an exercise in patience. And my plates kept slipping a sixteenth inch here and there. In the end I don't think it will be terribly noticeable.


And then deburred the holes by spinning a 1/2" but by hand from both sides. Finally, broke the sharp edges of the plate with a hand file just so we have a nicer finished product. A keen eye will notice that I drilled 16 holes per plate...see I bought enough hardware for 14 holes per plate as that was my intent. Little brainfart when marking my hole locations gave me some extra marks and thus, extra holes. Another couple packs of hardware will be needed.

Total investment update: $230

 

[JC in GB]

Glad to see that you are getting that thing up to par. That is the reason that I ultimately gave up on my Dyna-glo. Cost of mods were more than cost of smoker. Hope you get a successful result.

JC

 

[jmtyndall]

Got the first side all sealed up and did a couple of test-smokes this weekend. Using the fire-bricks it was taking so long to come up to temp I pulled them out and just filled the basket with coals. Was easily able to maintain ~375 to smoke a chicken with the vents mostly closed.

Second smoke was a pork tenderloin so the target was 225F. I should have tried the bricks again. Overshot the temp and ended up smoking it at 325 the whole time. Still came out good, but it's going to take some adjustments. For the next low-temp smoke I'm going to try with the bricks back in the basket.

Anyways, glad I used thick steel for the blank-off because I discovered the box of my smoker was in fact a bit warped. That may be part of the reason the stock dampers leak so much air. Anyways, with the plate on and the bolts tightened down it all flattens out pretty well. Didn't see any smoke leaks during my tests.

 

[jmtyndall]

Haven't had a ton of work on this the last couple weeks. Lots of work on the baby nursery getting in the way. My smoke stack and pinwheel damper came in a while back so I want to get those installed. First project is going to be the smoke stack. The one I got from Lavalock isnt level across the top. When you bolt the damper onto the stack it sits up at an angle so that theres about 1/16" gap between the pipe and the damper. That won't do at all. I'll get a picture tonight.

So the plan is to take the belt sander to it until the surface is nice and planar so that when I put the damper on it actually closes off the exhaust vent!

Also my amazing wife spotted a smoker on the side of the road this week with a "Free" sign. Looked back around and picked up this Oklahoma Joe.
Total bear to load into the car, but I didnt have it in my heart to leave a homeless smoker out on the street. So these two will be competing for my attention.

 

[jmtyndall]

Finally had a chance to put in some more work on this. Decided that the smoke stack was the next upgrade to do. The stack itself left a little to be desired, for instance the bottom flange wasn't fitted well and the inside opening was a smaller diameter than the pipe itself. Fairly easy fix to throat it out a bit so that it no longer caused a restriction. Also the top flange where the damper mounts wasn't flat. With the damper bolted on, there was a gap of about 1/16" between the pipe flange and the damper. I tried to take a hammer and flatten this out, but accomplished nothing except making a lot of noise. Second choice was to sand it flat, which also didn't do anything except get the thing hot. In the end I shimmed the bolt so that the damper laid flat against the flange. Painted it all up and got it mounted.


Last thing on my list is to fix the remaining inlet damper so that I can get better control. The problem is that I bought a pinwheel style damper and that leaves me with a rather complex hole to cut in my 16ga plate. I tried to make a test cut using my jigsaw, however I wasn't able to get a result I was happy with. Not really sure what direction to go from here, maybe scrap the pinwheel and move to something like a slide-damper instead, or else leave it as-is. Unless I stumble across a great deal on a laser-cutter at a garage sale.