UDS Heat Shield & Biscuit Test (Pictorial)

Thawley · 08-02-2009, 09:13 PM

Burnig coals – very hot

Make shift heat shield/baffle/diffuser – 10x10x0.25" mild steel plate

Fire basket & diffuser in their native environment

U-bakem biscuits – the natural enemy of burning coals

Ritual of sacrifice

It's a little warmer on the west side. (Photo taken facing south) Ironically, the air inlets below the grate are at 12 & 6 o'clock. Heat should be even from east to west. I can only assume that the Earth's rotation is somehow affecting the combustion airflow. No doubt the heat distribution would be reversed in the southern hemisphere.

Saiko · 08-02-2009, 09:17 PM

Wow, pretty big difference between the left side and the right side. What do you think is the cause? It's a verticle smoker, so it seems like the temps should have been more consistent. Maybe a circular heat shield larger than the diameter of the charcoal basket would even things out, dunno.

mranum · 08-02-2009, 10:10 PM

Is the change anywhere near the exhaust vent? That could maybe do it.

Thawley · 08-02-2009, 10:22 PM

Exhaust is centered. Though I suppose it's possible the bend somehow affects the airflow, I kind of doubt it. Besides – that bend keeps the rain out. It's staying.

landarc · 08-02-2009, 10:25 PM

It might be worth doing another test just to make sure of the results. Maybe even turn the shield 45 degrees and see what happens.

Thawley · 08-02-2009, 11:11 PM

To be honest, this is a big improvement over what it did without the steel plate. I did the same a while back (before iPhone) so no photos. But the center of the grate was WAY hotter than the edges.

Still got a ways to go though.

Kubbie · 08-02-2009, 11:44 PM

Interesting test. I need to try this a few times. (Plate, no plate, changing exhaust position...)

Noticed it again yesterday on a load of ABT's. One side was get done faster. I would spin the rack and rotate the lid so the exhaust would be in a different part. (Sorry - no after pic on this load - and as fast as they went, I needed to make about 3 times as much!)

I have a shorter but wider basket - about 17" wide and 5" of height.
You can just see in the second pic that when I start it in the middle, it doesn't always work itself out evenly in the first few hours or the burn (or if I have something smoking that is a heavy dripper)

I thought it was my 2" exhaust that is to the side (flat lid). Need to get to know the drum better.

HoosierTrooper · 08-03-2009, 05:30 AM

I added a grate 4 inched above the charcoal basket with a foiled water pan setting on it, WSM style, as a diffuser. I have 8 1/2 inch holes in the lid and never noticed any hot spots but since adding the pan I really like the results better than when the fat was dripping on the coals and wood.

Bbq Bubba · 08-03-2009, 05:39 AM

It's obvious your drum is sitting crooked. This explains everything.

Rick's Tropical Delight · 08-03-2009, 05:44 AM

the west side is always warmer after noon.

did you eat those muffins or throw them at passsing cars?

Thawley · 08-03-2009, 10:01 AM

Quote:

Originally Posted by Rick's Tropical Delight

did you eat those muffins or throw them at passsing cars?

Butter & syrup for breakfast baby...

Hog Warden · 08-03-2009, 11:45 AM

Thawley:

Great information! I have concluded the UDS is about as idiot proof and reliable as anything I've ever used to cook with.....but all things can be improved on and I've been thinking for a while these things need a baffle of some type to separate the meat from the fire.

My unit....

Ash pan is a lid from a 30 gallon drum. Last smoke of baby backs, I used the ash pan from my ECB, setting the charcoal basket in that, and the 30 gallon lid on top of the charcoal basket. Worked just as well and eliminated some of the "blackened" look and taste, and some of the "burnt" smell coming from the stack during the smoke....

End results.....

Up next is a full packer brisket......same process.

HW (Who has been Matchlight free for years.......)

mgwerks · 08-03-2009, 05:46 PM

Any chance there was a breeze blowing? That would cool the windward side a tad.

Countryhb · 08-03-2009, 05:59 PM

Quote:

Originally Posted by Thawley

Besides – that bend keeps the rain out.

So that bend works twice a year??? You sure you don't mean that the bend keeps the sprinkler out???

Thawley · 08-03-2009, 08:38 PM

Quote:

Originally Posted by Countryhb

So that bend works twice a year???

Dude, my bend works every time.

08-02-2009, 09:13 PM	#1
Thawley Take a breath! Join Date: 06-17-07 Location: Disneyland Downloads: 0 Uploads: 0	UDS Heat Shield & Biscuit Test (Pictorial) Burnig coals – very hot Make shift heat shield/baffle/diffuser – 10x10x0.25" mild steel plate Fire basket & diffuser in their native environment U-bakem biscuits – the natural enemy of burning coals Ritual of sacrifice It's a little warmer on the west side. (Photo taken facing south) Ironically, the air inlets below the grate are at 12 & 6 o'clock. Heat should be even from east to west. I can only assume that the Earth's rotation is somehow affecting the combustion airflow. No doubt the heat distribution would be reversed in the southern hemisphere. __________________ E. John Thawley III UUDS™ Thawley on Tumblr

08-02-2009, 09:17 PM	#2
Saiko is Blowin Smoke! Join Date: 12-24-03 Location: Kennesaw, GA Downloads: 0 Uploads: 0	Wow, pretty big difference between the left side and the right side. What do you think is the cause? It's a verticle smoker, so it seems like the temps should have been more consistent. Maybe a circular heat shield larger than the diameter of the charcoal basket would even things out, dunno. __________________ Shelter me from the powder and the finger Cover me with the thought that pulled the trigger Think of me as one you'd never figured Would fade away so young With so much left undone For links to all my BBQ Brethren recipe posts, click http://markandteri.com/recipes.htm

08-02-2009, 10:22 PM	#4
Thawley Take a breath! Join Date: 06-17-07 Location: Disneyland Downloads: 0 Uploads: 0	Exhaust is centered. Though I suppose it's possible the bend somehow affects the airflow, I kind of doubt it. Besides – that bend keeps the rain out. It's staying. __________________ E. John Thawley III UUDS™ Thawley on Tumblr

08-02-2009, 10:25 PM	#5
landarc somebody shut me the fark up. Join Date: 06-26-09 Location: San Leandro, CA Downloads: 0 Uploads: 0	It might be worth doing another test just to make sure of the results. Maybe even turn the shield 45 degrees and see what happens. __________________ "perhaps...but then again...maybe not..." careful there son, those ribs are boiling hot... \_\|_/ (='.'=) Here there be bunnies... (")_(")ooo Pacific Rim BBQ Bob's Brew and Que

08-02-2009, 11:11 PM	#6
Thawley Take a breath! Join Date: 06-17-07 Location: Disneyland Downloads: 0 Uploads: 0	To be honest, this is a big improvement over what it did without the steel plate. I did the same a while back (before iPhone) so no photos. But the center of the grate was WAY hotter than the edges. Still got a ways to go though. __________________ E. John Thawley III UUDS™ Thawley on Tumblr

08-02-2009, 10:10 PM	#3
mranum Full Fledged Farker Join Date: 05-03-09 Location: Wisconsin Rapids, WI Downloads: 0 Uploads: 0	Is the change anywhere near the exhaust vent? That could maybe do it.

08-02-2009, 11:44 PM	#7
Kubbie Knows what a fatty is. Join Date: 06-10-09 Location: Mt. Prospect, IL Downloads: 0 Uploads: 0	Interesting test. I need to try this a few times. (Plate, no plate, changing exhaust position...) Noticed it again yesterday on a load of ABT's. One side was get done faster. I would spin the rack and rotate the lid so the exhaust would be in a different part. (Sorry - no after pic on this load - and as fast as they went, I needed to make about 3 times as much!) I have a shorter but wider basket - about 17" wide and 5" of height. You can just see in the second pic that when I start it in the middle, it doesn't always work itself out evenly in the first few hours or the burn (or if I have something smoking that is a heavy dripper) I thought it was my 2" exhaust that is to the side (flat lid). Need to get to know the drum better. Last edited by Kubbie; 08-03-2009 at 12:02 AM..

08-03-2009, 05:30 AM	#8
HoosierTrooper Full Fledged Farker Join Date: 06-25-07 Location: Jeffersonville, Indiana Downloads: 0 Uploads: 0	I added a grate 4 inched above the charcoal basket with a foiled water pan setting on it, WSM style, as a diffuser. I have 8 1/2 inch holes in the lid and never noticed any hot spots but since adding the pan I really like the results better than when the fat was dripping on the coals and wood. __________________ Chargriller with side fire box Two WSM's-18.5 and 22.5 Masterbuilt electric Certified MOINK Baller 11-9-08

08-03-2009, 05:39 AM	#9
Bbq Bubba somebody shut me the fark up. Join Date: 05-03-07 Location: New Baltimore, Mi. Downloads: 0 Uploads: 0	It's obvious your drum is sitting crooked. This explains everything. __________________ Pitmaster @ Lockharts BBQ Beer Snob I cook the best brisket north of Dallas. Get over it. Northern midwest director for OBR www.operationbbqrelief.com

08-03-2009, 05:44 AM	#10
Rick's Tropical Delight Permanent Timeout Join Date: 04-25-07 Location: Farmersville, Ohio Downloads: 0 Uploads: 0	the west side is always warmer after noon. did you eat those muffins or throw them at passsing cars?

08-03-2009, 11:45 AM	#12
Hog Warden Found some matches. Join Date: 07-28-09 Location: Columbia, MO Downloads: 0 Uploads: 0	Thawley: Great information! I have concluded the UDS is about as idiot proof and reliable as anything I've ever used to cook with.....but all things can be improved on and I've been thinking for a while these things need a baffle of some type to separate the meat from the fire. My unit.... Ash pan is a lid from a 30 gallon drum. Last smoke of baby backs, I used the ash pan from my ECB, setting the charcoal basket in that, and the 30 gallon lid on top of the charcoal basket. Worked just as well and eliminated some of the "blackened" look and taste, and some of the "burnt" smell coming from the stack during the smoke.... End results..... Up next is a full packer brisket......same process. HW (Who has been Matchlight free for years.......)

08-03-2009, 05:46 PM	#13
mgwerks Full Fledged Farker Join Date: 04-19-09 Location: Bandera, Texas Downloads: 0 Uploads: 0	Any chance there was a breeze blowing? That would cool the windward side a tad. __________________ Visit my (mostly) cooking blog at texascookin.blogspot.com.

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