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Sponge
06-07-2017, 02:08 AM
Hi Guys,

I've already gleaned a lot from you knowledgable smokers out there.

I'm looking to build my first UDS/BBQ/Pizza Oven, and have a few Qs.

I've got all the low-down on the standard UDS set-up, but was thinking of a few "modifications" to make the unit more versatile.

A good temp for a pizza oven is between 300 to 600 degrees C (sorry, I'm an Aussie, and don't have much of an idea about fahrenheit). I'm guessing that a "standard" UDS would be about 120 degrees C on the top grill (say 50mm, sorry 2 "inches" from top of drum - using a Webber lid). I have a few Qs for the gurus, to make sure I'm not going to make a mess of what is truly an awesome American invention.

1. Under normal operation, what kind of temps can I expect for 2 inches, 8 inches, and 14 inches from the top, of the drum, assuming the basket sits between 4 inches and 16 inches from the bottom?
2. Am I likely to be being incinerated when retrieving/placing meat on a grill 14 inches down from the top of the drum?
3. Do you see any problems if I were to have 6 x 3/4 inch inlets at the bottom, 3 with ball valves, 3 with plugs?
4. What kind of temps should I expect at same grill heights above with 3 valves fully open; 6 valves fully open?
5. Could I use Besser (concrete) blocks in the bottom of the UDS to raise by basket up to get heat closure to BBQ grill/pizza tray? (back-up plan if answer to 2. above is "yes - duffus!")
6. Does a snug-fitting Webber lid create any dramas?
7. If I was brave/stupid? and really wanted to build a side door (for pizza oven - of course), would it work if I lined the opening on the inside with 1.5 inch flashing from another drum, use a gasket tape on the lining or door, and used a clamp latch to close it?
8. Any other tips/ideas of how I might be able to build such a unit?

Cre-B-Ce
06-07-2017, 07:52 AM
I never did anything but low and slow on mine. The best inlet I used on mine was a Big Green Egg draft door. Much easier to me than trying to adjust multiple ball valves and should be plenty of air flow if you need to open it up for higher temps.

Sponge
06-07-2017, 09:08 AM
Thanks Crue-B-Cue,

Does the Big Green Egg draft door seal well (for low end temperature control)?

Do you get problems with uneven burn?

What do you think of putting one on each side - to get balance, and maximise draft for high temps?

kls44
06-07-2017, 09:34 AM
I built mine with adjustable shelving hardware, so the grates(2) can be set anywhere needed, takes the guesswork of where to put the grate supports. It was only extra $10.

Sponge
06-07-2017, 09:42 AM
Great idea! thanks kls44

Cre-B-Ce
06-07-2017, 09:42 AM
Thanks Crue-B-Cue,

Does the Big Green Egg draft door seal well (for low end temperature control)?

Do you get problems with uneven burn?

What do you think of putting one on each side - to get balance, and maximise draft for high temps?

I could hold 250 for 12 hours easily with my charcoal basket. Never had uneven temps. I'll see if I can find some pictures. It's been a while.

Sponge
06-07-2017, 09:46 AM
For a pizza oven, I'm thinking high temps for a short period - just like a wood fired oven in a restaurant - pizzas cook in a couple of minutes.
So it sounds like 2 of those draft doors would probably do the trick.
Do you need to apply some kind of sealant to avoid unwanted leakage for when the door is closed?

ebijack
06-07-2017, 09:46 AM
I believe you are looking to build something like what I have. When I build a "new one" It won't have all the things I tried/experimented with, only what is required from my type cooking. I can run from 180 deg F to well over 750 deg F. I also am able to burn pure wood using my access door for that style cooking.
IMHO, you will require a 4" exhaust to be able to do the high temp cooks/searing. Or modify a Weber style lid/bottom with a large opening for high temp cooks.
http://imagizer.imageshack.us/v2/640x480q90/922/9Eg4dM.jpg (https://imageshack.com/i/pm9Eg4dMj)
I tried having the coals/wood chunks only a few inches below from the pizza/grate and stone.
http://imagizer.imageshack.us/v2/640x480q90/923/yIwWmK.jpg (https://imageshack.com/i/pnyIwWmKj)
but found I prefer to just burn pure wood down in my basket sitting 3 inches above the bottom ( 3" legs on my 17" basket. I am able to keep the temps up high for pizza. More so than with the coal/wood. If that makes sense.
I used 1/2"X 1/8" steel to add support where I cut the opening of the bottom (now top) of a knock off Weber bottom. The reason being the bottom/lid sits on 3 bolts where the grate sits. Without that piece, you had to be real careful how you set the lid back on or it would tend to fall/tip. With this lid, you don't have to remove the lid during cooking and lose all that heat.
http://imagizer.imageshack.us/v2/640x480q90/924/XZyac5.jpg (https://imageshack.com/i/poXZyac5j)
I also made a 4" riser/ring with 4 legs that I use when wanting to cook with pure wood. Like the 007 drum. Found I did not need/want to swing my grate at all like 007. Using the riser, you typically can not burn food. Works real nice. When really windy I use the pizza mod lid, no riser.
http://imagizer.imageshack.us/v2/640x480q90/924/VmWv9j.jpg (https://imageshack.com/i/poVmWv9jj)
http://imagizer.imageshack.us/v2/640x480q90/922/FsWjBj.jpg (https://imageshack.com/i/pmFsWjBjj)
http://imagizer.imageshack.us/v2/640x480q90/924/BkwdM2.jpg (https://imageshack.com/i/poBkwdM2j)
http://imagizer.imageshack.us/v2/640x480q90/923/B4liNO.jpg (https://imageshack.com/i/pnB4liNOj)
If you add/make an access door, you probably could use aluminum flashing pop riveted around the inside for the door to seal against. Again I used 1/8"X 1/2" Sheetmetal would be fine also. Easier to shape. I used high temp RTV as a sealer, but ended up just scraping that off...waste of time, and ugly.
http://imagizer.imageshack.us/v2/640x480q90/921/Mi4hO8.jpg (https://imageshack.com/i/plMi4hO8j)
Oversize your door from what you think you want. Mine works, but I think I'd go 1 to 2 " larger next time. Also, next time I will use a donar drum to cut a larger door from. No worry about sealing edges. If that makes sense.

Now for intakes. I have 4- 1.5" pipe elbows that I use for high heat cooks. I cook year round. Even in single digit temps and 30 mph winds. Cold and wind can affect the temps that are reached. Usually I only require 3, but there are times I use all 4.
http://imagizer.imageshack.us/v2/640x480q90/911/9TVVyD.jpg (https://imageshack.com/i/pb9TVVyDj)
I use magnets for temp control/shutdown. Easy to move/adjust with your feet. You have a visual of where the opening is set. Wind and or snow don't blow into the drum affecting my temps.
http://imagizer.imageshack.us/v2/640x480q90/538/5EdPeP.jpg (https://imageshack.com/i/ey5EdPePj)
An using the 1.5" elbows, you can add a fatman option for even easier temp control. But you can not get high temps with that added pipe height.
http://imagizer.imageshack.us/v2/640x480q90/537/ZKeEbe.jpg (https://imageshack.com/i/exZKeEbej)
I'd suggest using 3 bolts per level. First grate level, 1" down from the top lip. Next set of bolts down 6" for a drip pan or second cooking level.
http://imagizer.imageshack.us/v2/640x480q90/922/bnYZkE.jpg (https://imageshack.com/i/pmbnYZkEj)
You can use the top level bolts to add a hanging ring also. I made mine, but you could mod another grate.
http://imagizer.imageshack.us/v2/640x480q90/673/3qWpTS.jpg (https://imageshack.com/i/ip3qWpTSj)
http://imagizer.imageshack.us/v2/640x480q90/923/jVIsAt.jpg (https://imageshack.com/i/pnjVIsAtj)
Any questions, just ask. Hope that helps

Sponge
06-07-2017, 10:02 AM
Thanks ebijak - awesome stuff.

Do you have any trouble controlling the temp at low-temp cooking?
I here a lot of talk about needing to seal doors properly to achieve that.

ebijack
06-07-2017, 01:08 PM
Do you have any trouble controlling the temp at low-temp cooking? I here a lot of talk about needing to seal doors properly to achieve that.
No, but I do cook alot. It did not take long for the "buildup" to seal everything. Even my neighbor who never used anything like this. Did 2 cooks and he said he had no problem setting/holding the temps he wanted.
I had to go deliver my drum back to myself :boxing:
He wanted to keep it.
With my 17" basket, my drum will go 17 hrs @275 deg F untouched. More than I ever need.

bstomper
06-07-2017, 01:46 PM
I believe you are looking to build something like what I have. When I build a "new one" It won't have all the things I tried/experimented with, only what is required from my type cooking. I can run from 180 deg F to well over 750 deg F. I also am able to burn pure wood using my access door for that style cooking.
IMHO, you will require a 4" exhaust to be able to do the high temp cooks/searing. Or modify a Weber style lid/bottom with a large opening for high temp cooks.
http://imagizer.imageshack.us/v2/640x480q90/922/9Eg4dM.jpg (https://imageshack.com/i/pm9Eg4dMj)
I tried having the coals/wood chunks only a few inches below from the pizza/grate and stone.
http://imagizer.imageshack.us/v2/640x480q90/923/yIwWmK.jpg (https://imageshack.com/i/pnyIwWmKj)
but found I prefer to just burn pure wood down in my basket sitting 3 inches above the bottom ( 3" legs on my 17" basket. I am able to keep the temps up high for pizza. More so than with the coal/wood. If that makes sense.
I used 1/2"X 1/8" steel to add support where I cut the opening of the bottom (now top) of a knock off Weber bottom. The reason being the bottom/lid sits on 3 bolts where the grate sits. Without that piece, you had to be real careful how you set the lid back on or it would tend to fall/tip. With this lid, you don't have to remove the lid during cooking and lose all that heat.
http://imagizer.imageshack.us/v2/640x480q90/924/XZyac5.jpg (https://imageshack.com/i/poXZyac5j)
I also made a 4" riser/ring with 4 legs that I use when wanting to cook with pure wood. Like the 007 drum. Found I did not need/want to swing my grate at all like 007. Using the riser, you typically can not burn food. Works real nice. When really windy I use the pizza mod lid, no riser.
http://imagizer.imageshack.us/v2/640x480q90/924/VmWv9j.jpg (https://imageshack.com/i/poVmWv9jj)
http://imagizer.imageshack.us/v2/640x480q90/922/FsWjBj.jpg (https://imageshack.com/i/pmFsWjBjj)
http://imagizer.imageshack.us/v2/640x480q90/924/BkwdM2.jpg (https://imageshack.com/i/poBkwdM2j)
http://imagizer.imageshack.us/v2/640x480q90/923/B4liNO.jpg (https://imageshack.com/i/pnB4liNOj)
If you add/make an access door, you probably could use aluminum flashing pop riveted around the inside for the door to seal against. Again I used 1/8"X 1/2" Sheetmetal would be fine also. Easier to shape. I used high temp RTV as a sealer, but ended up just scraping that off...waste of time, and ugly.
http://imagizer.imageshack.us/v2/640x480q90/921/Mi4hO8.jpg (https://imageshack.com/i/plMi4hO8j)
Oversize your door from what you think you want. Mine works, but I think I'd go 1 to 2 " larger next time. Also, next time I will use a donar drum to cut a larger door from. No worry about sealing edges. If that makes sense.

Now for intakes. I have 4- 1.5" pipe elbows that I use for high heat cooks. I cook year round. Even in single digit temps and 30 mph winds. Cold and wind can affect the temps that are reached. Usually I only require 3, but there are times I use all 4.
http://imagizer.imageshack.us/v2/640x480q90/911/9TVVyD.jpg (https://imageshack.com/i/pb9TVVyDj)
I use magnets for temp control/shutdown. Easy to move/adjust with your feet. You have a visual of where the opening is set. Wind and or snow don't blow into the drum affecting my temps.
http://imagizer.imageshack.us/v2/640x480q90/538/5EdPeP.jpg (https://imageshack.com/i/ey5EdPePj)
An using the 1.5" elbows, you can add a fatman option for even easier temp control. But you can not get high temps with that added pipe height.
http://imagizer.imageshack.us/v2/640x480q90/537/ZKeEbe.jpg (https://imageshack.com/i/exZKeEbej)
I'd suggest using 3 bolts per level. First grate level, 1" down from the top lip. Next set of bolts down 6" for a drip pan or second cooking level.
http://imagizer.imageshack.us/v2/640x480q90/922/bnYZkE.jpg (https://imageshack.com/i/pmbnYZkEj)
You can use the top level bolts to add a hanging ring also. I made mine, but you could mod another grate.
http://imagizer.imageshack.us/v2/640x480q90/673/3qWpTS.jpg (https://imageshack.com/i/ip3qWpTSj)
http://imagizer.imageshack.us/v2/640x480q90/923/jVIsAt.jpg (https://imageshack.com/i/pnjVIsAtj)
Any questions, just ask. Hope that helps


Ah....err....What he said^^^^
Ebijack pretty much explained everything you need to know to accomplish what you need. He has some great ideas. I really like the hanging rack mod, im gonna make one for smoking sausage.
Air flow is the key to get the high temps. I think fewer larger ones will work beter than more smaller ones.

Nuco59
06-07-2017, 07:01 PM
Just my 2cents- but if I was going to cook a "lot" of pizzas, I would not hack up my smoking drum to do it. Why cut it up just to sweat how best to seal it up? There are TONS of videos on how to make simple brick stack wood fired pizza ovens that will cook a true wood fired pizza.