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boiler93
04-04-2013, 09:24 PM
I have a new offset reverse flow smoker and i have very little experience Qing on this size rig. I feel like I'm losing too much heat from the smoker door. How much smoke/heat can you expect to be loss from here and are there any quick mods to remedy the situation?

Related problem(??) is that it takes about an hour for the temp to reach 225 with the box full of oak sticks and can't seem to get higher than about 240.

The smoker itself measures 36x60 and the firebox measures 20x 24.

Any and all help is appreciated!

El Ropo
04-04-2013, 09:30 PM
you haven't mentioned how much intake you are giving it. Franklin actually cracks his firebox doors open to allow more oxygen to get to the fire.

Many less than perfect offset COS cookers don't have large enough intake holes to allow for good draft. Easy solution is to crack the firebox door open and get a nice small clean fire goin.

On the smoker door, I'm sure it'll help to keep it closed. If there are signs of huge leaks in the door, a gasket kit might help.

Pyle's BBQ
04-04-2013, 09:33 PM
How big are the sticks you are starting with? You will have heat loss, but an hour is not that long to get to temp. Have you calibrated the thermometer so you know that it is accurate?

boiler93
04-04-2013, 09:46 PM
I have three nice sized air intakes: 2 on the side and 1 in the rear. I have not tested the accuracy of the thermometer but that is first on my list this weekend.

The sticks that i'm using are about 18 inches. Where can I locate a gasket kit if this ends up being the issue?

Bludawg
04-04-2013, 10:33 PM
What make is it and why do want to cook at such low temps? if it is a heavy gauge pit 1 hr is pretty decent to come up to temp. Offsets are all about draft and fire management>It could be you have to much fuel in the box at once blocking up your air flow to the fire. That will greatly reduce the air space needed for good combustion. It is better to have a small hot fire and develop a good coal base and gradually increase the fire size over time until you reach your desired cooking Zone IE 275-325.
I start out with a 1/2 bag of lump and 2 splits to establish a coal base the 1 preheated split every 45-1 hr to maintain my Zone. One thing you can do to increase the draft and get to temp sooner is to place a pan of coals on the grate on the far end of the pit to pull the cool air through the firebox thereby increasing the efficiency, then remove it as you get close to operating temp.

TuscaloosaQ
04-04-2013, 10:43 PM
In my opinion you firebox is undersized for that size cooker!!!!!!!!!

boiler93
04-04-2013, 10:48 PM
Im trying to accomplish/master similar temp zones as you mentioned. I would like the ability to cook from 225 to 325 depending on the food. I recent purchased an Model A1 from custom pits and probably need more grill time to find out how she works. I guess I'm a little impatient being a results orientated guy (too many years playing and coaching football). Just checked her out and temp is up to about 265 after about 1.75 hrs. I appreciate all the advice!

boiler93
04-04-2013, 10:50 PM
In my opinion you firebox is undersized for that size cooker!!!!!!!!!
What size would be adequate?

TuscaloosaQ
04-05-2013, 06:16 AM
What size would be adequate?

Well you only give 2 numbers 20x24 what is the other number??? If I am correct about the cooker being 36ODx60long and the above numbers are right your last number is going to have to be really big. You give me the length width and height and I can get you spot on, on the size it should be. I am assuming it is a rectangular fireox. If it is round and the above size again you are really very small. It is not about how big of a fire you build, many people over fire their cookers, if the firebox is sized right then it is better to start out small and to keep it stabilized feed it regular and consistent. Bigger aint always better on a fire!!!!!!! The right intake, exhaust, and firebox is the key. No need to have to over fire a cooker

ButtBurner
04-05-2013, 06:23 AM
posting pics of the pit would help too. Including one of the opening between the firebox and cook chamber

jacksedona
04-05-2013, 06:33 AM
you have not mentioned the weather conditions which contribute much to heat loss. what is the tempersature where you are? what is the wind speed?
is the smoker protected from wind? these factors can dranaticallty lower your internal temperature. when i lived in ny state i had my smokers located near several walls to protect them from wind

http://thebarbecuemaster.net

posey's_pork_pit
04-05-2013, 06:41 AM
If yours is like the one on their website, may I suggest the following:

When heating up, do not allow air flow from the cooking chamber to the warming box

The 2 side intakes, keep the top one closed and the bottom one wide open. The top one looks a bit high to me. Also keep the exhaust wide open. You want inbound air to flow under you coal bed not over it. I don't see a back intake in the picture but if it's high like the side one, I would keep it closed as well.

http://www.custompits.com/Bbq-Smokers.html

dwfisk
04-05-2013, 06:50 AM
Looked up your pit online.
http://www.custompits.com/Bbq-Smokers.html
It does look like a nice rig, but I to am a little concerned the firebox is a little small in relationship to the cook chamber and warmer. Here is what I would do:
1) Double check the thermometers!
2) Make sure you have a clean, hot fire. IMO a smaller hot fire is better than cramming it full and choking it down. I start small & hot, build a bed of coals then build it up to the size I need depending on how hot & long I'm going to cook.
3) I would not fret about an hour to get all that steel up to temp. Mine is 24x72 and can take 30-45 minutes.
4) + 1 on what Bludawg & TuscaloosaQ are saying.
Good luck, It really does look like a nice rig, I'm sure you will get it figured out.

dwfisk
04-05-2013, 06:59 AM
Hey neighbor, I just noticed I'm only 45 minutes down I75 (I'm in between Gianesville and Ocala). Since you are so close, one more tip: I've been using kiln dried hickory that it supposed to have <14&#37; moisture. Don't know about that but ut sure burns clean and hot. Anyhow, Southern Fuelwoods is just down the road from you in Newberry.
http://www.southernfuelwood.com/
Good luck.

boiler93
04-05-2013, 09:14 AM
Thanks for all the tips. I will definitely start with a smaller fire and add to it. Watched a small video on the lang site and he seemed to stuff it full of fuel but i may be wrong??

The two air intakes on the side are parallel to each other not sure how it looks on website and both are near the the bottom-half of the box, that being said i guess they could be lower. I will post pictures this weekend.

buttburnersbbq
04-05-2013, 08:17 PM
I have a reverse flow smoker I built . Main chamber is 30" x 72" and my fire box is 25"w x 18" L x 18" h . I have over sized my intakes that are adjustable. Also in my fire box my fire is on a stand so intakes are under rack in fire box. Which air is forced from under the fire and all heat and smoke is drawn through the main chamber. I have no issues on temp . It dose take a hour or so to get up to temp but only have to add one split per hour. You want your pit o run s efficient as possible. Look at air intake o make sure they are low enough and draw he heat and smoke to the main chamber. Second you need to make sure your exhaust is big enough. If you don't get enough draw you will starve your fire and will ill not be able to achieve temp you want.

boiler93
04-06-2013, 11:02 PM
Having trouble posting pics and don't know why (size within requirements). The box is 24Wx20Lx20D which should be large enough. The temp here in florida is mid to high 70s with little wind again not the problem. I have three med-large intakes below fire level so not sure where my issue is. Cooked again today and chick and ribs turned out good but would rather cook the chicken at 300 and can't get there. Have a small brisket on but don't want to stay up all night so Im getting ready to transfer to the bradley smoker it will stay at 225 all night without me. If anyone can help this newbie post pics, i would still enjoy everyone's thought on how to get the temp up in my smoker, thanks!

boiler93
04-07-2013, 04:28 PM
Finally figured out photo using photo bucket!

http://i1325.photobucket.com/albums/u627/puboiler93/IMG_0318_zps8df6252c.jpg
http://i1325.photobucket.com/albums/u627/puboiler93/photocopy_zpsc1d6d3cd.jpghttp://i1325.photobucket.com/albums/u627/puboiler93/photo_zpsd9f6425f.jpghttp://i1325.photobucket.com/albums/u627/puboiler93/photocopy2_zps1465e5bc.jpghttp://i1325.photobucket.com/albums/u627/puboiler93/photocopy3_zpse1a5be9b.jpg

As stated in the above post I'm still having trouble getting her above 260 and would love to get her to 300. All suggestions are welcome!

Smokin'Butts
04-07-2013, 07:11 PM
Just wondering where you got the smoker? I am looking at one just like it....never mind, just found it. Did you just pick it up yesterday? I was actually just at custom pits yesterday and I had my hands all over your pit I think...lol. It is a super nice pit. Just from looking at your pics, are your stacks closed when you are trying to get it up to temp?

morgaj1
04-07-2013, 07:33 PM
I still think that your firebox is too small. Take a look at this calculator:

http://www.feldoncentral.com/bbqcalculator.html

Based on the formula from this website, your pit should have a firebox of 20,347 cubic inches. You only provided 2 of the 3 dimensions of the firebox. But, assuming that your firebox is 24"x24"x20", you have a firebox volume of 11,520 cubic inches. So, based on these numbers, your firebox is only 56.6% as big as it should be. A firebox of 28"x28"x26" would be the perfect size.

boiler93
04-07-2013, 07:53 PM
I still think that your firebox is too small. Take a look at this calculator:

http://www.feldoncentral.com/bbqcalculator.html

Based on the formula from this website, your pit should have a firebox of 20,347 cubic inches. You only provided 2 of the 3 dimensions of the firebox. But, assuming that your firebox is 24"x24"x20", you have a firebox volume of 11,520 cubic inches. So, based on these numbers, your firebox is only 56.6% as big as it should be. A firebox of 28"x28"x26" would be the perfect size.

Is there anything I can do short of ripping the existing firebox and warming box off and fabricating a new one? Because i don't have those skill sets.

dwfisk
04-07-2013, 07:53 PM
OK, great pics, thanks for adding them. Is the exhaust the single square tube or the 2@ crome tubes or both/all? Looks to me like you have your exhust closed or choked down. I suggest you open your exhausts wide open and leave them alone; control your fire with the intakes! I still think its a great lookin pit and you will figure it out!

Smokin'Butts
04-07-2013, 07:58 PM
I was thinking the same thing as dwfisk...they looked closed. dwfisk.....there are actually 2 square exhaust tubes on this smoker. The 2 chrome tubes are for the rear charcoal grill only. I have seen these smokers personally and I cannot see why they would have trouble getting up to temp. Granted, I do not have one and I do not speak from experience...Let us know when you get it figured out though please.

boiler93
04-07-2013, 08:04 PM
OK, great pics, thanks for adding them. Is the exhaust the single square tube or the 2@ crome tubes or both/all? Looks to me like you have your exhust closed or choked down. I suggest you open your exhausts wide open and leave them alone; control your fire with the intakes! I still think its a great lookin pit and you will figure it out!

Not a great pic of the exhaust (its actually not shown due to the warming box being in the way). First, the 2 chrome exhausts are strictly for the 3x5 charcoal grill on the end-nice option. The other exhaust that is shown in the pic stays closed since it is a reverse flow smoker don't know why it has that one but custom pits said to keep it closed and after the 6 hr trip to p/u i didn't ask enough questions!

Smokin'Butts
04-07-2013, 08:09 PM
I actually just emailed with Brad from Custom Pits. He told me that starting this week they are increasing the exhaust from 3" to 5" so that should help with the airflow.

morgaj1
04-07-2013, 08:11 PM
Is there anything I can do short of ripping the existing firebox and warming box off and fabricating a new one? Because i don't have those skill sets.

I don't think so. However, I still think you should be able to reach 300*F. Do you have a flap that you can close to the warming box? If so, I would close that and open your smokestacks completely. Then play with the intake vents and fire size. You may even want to crack the door to the firebox and see if you can get better air flow.

dwfisk
04-07-2013, 08:13 PM
OK, so from your response and Smokin'Butts I'm assuming there is another square exhaust "hidden" in the pics behind the warming cabinet/firebox. Is it wide open & how big is it (the one on the other end that is closed looks to be a 3"x3")? If your exhaust is only 3"x3" I hate to say it but you gotta a problem - thats not anywhere near enough for your pit!

Smokin'Butts
04-07-2013, 08:23 PM
boiler93.....in emailing with Brad he would like to speak with you to see what he can do to fix it. Send me a PM if you would like or give him a call

dwfisk
04-07-2013, 08:26 PM
Sorry, last post was a little negative. This can be fixed! Either the mfg or I'm only 45 minutes down the road. Don't get too frustrated, you can get it workin!

boiler93
04-07-2013, 08:40 PM
Thanks smokin'butts and dwfisk, I will contact the mfg tomorrow to see what I can find out. Ive seen pics of people modifying their exhausts by lowering it to grate level-what does this mod accomplish?

Morgaj1: no opening or vent into warming box to close

dwfisk
04-07-2013, 08:47 PM
I did this when I built mine, put the intake for the exhaust down to the top grate level. I read it forced more smoke on te meat, seems to work pretty good. I'm hopin the mfg can make it right, if not I'm just down the road.

PS: your fire box is on the small size, but not so small as to think replacing it - get the exhaust & air flow right first!

PalmettoSmoke
04-07-2013, 08:53 PM
I have this exact pit (without warming box). I agree that the exhaust is too small. I may give them a call to see if I can retrofit a larger one on mine.

boiler93
04-07-2013, 09:04 PM
I have this exact pit (without warming box). I agree that the exhaust is too small. I may give them a call to see if I can retrofit a larger one on mine.

Are you having similar issues getting above 260? How long have you had yours?

PalmettoSmoke
04-07-2013, 09:49 PM
I've had it up to 275, but it takes a LOT of fuel. There are quite a few leaks in the pit. I plan to get some red silicone or fire rope stuff to seal it up better. That should help with temps.

I've had mine for about a month. I've done 3 cooks on it. I found lump was better than Kingsford for the coal (lump burns hotter). I also found a guy who sells oak and hickory firewood. The bigger logs help tremendously over the small chunks you get from the store.

mikeleonard81
04-07-2013, 11:42 PM
I just baught the same rig this weekend. Do you think insyalling a bbq guru would help? I wasen't so concerned with the heat up time(an hour isn't that long for all that steel I dont think) but getting it to hold at 250 is a problem i found out seasoning it yesterday.

PalmettoSmoke
04-08-2013, 05:58 AM
I just baught the same rig this weekend. Do you think insyalling a bbq guru would help? I wasen't so concerned with the heat up time(an hour isn't that long for all that steel I dont think) but getting it to hold at 250 is a problem i found out seasoning it yesterday.

Before installing a guru, you're going to have to deal with the leaks. You'll probably need two 25 CFM fans for it.

dwfisk
04-08-2013, 06:28 AM
Hey boiler93, just though of a cheap experiment to test the theory that the exhaust it to small. As I understand it you have two 3x3 square exhausts but the mfg has said keep the one opposite the firebox closed for RF cooking. I absolutely agree with the mfg IN THEORY but thats limiting your exhaust capacity to one 3x3 or 9 sq inches. But, before spending $'s or considering chopping the pit, why not try a run with both exhausts open just to see if it improves the fire & pit temp. Also a note from others that have the pit and reference "leaking smoke everywhere" - to me that is confirming the exhaust capacity is to small and the smoke is looking for somewhere to go. Bet if you can get the exhaust & intake balanced the leaks will stop also.

boiler93
04-08-2013, 07:02 AM
Hey boiler93, just though of a cheap experiment to test the theory that the exhaust it to small. As I understand it you have two 3x3 square exhausts but the mfg has said keep the one opposite the firebox closed for RF cooking. I absolutely agree with the mfg IN THEORY but thats limiting your exhaust capacity to one 3x3 or 9 sq inches. But, before spending $'s or considering chopping the pit, why not try a run with both exhausts open just to see if it improves the fire & pit temp. Also a note from others that have the pit and reference "leaking smoke everywhere" - to me that is confirming the exhaust capacity is to small and the smoke is looking for somewhere to go. Bet if you can get the exhaust & intake balanced the leaks will stop also.

Waiting to hear back from mfg, but you took the words right out of my mouth. I will play with the 2nd exhaust a little at a time and see if I can get it to draw more heat into the cooking chamber and still work RF.

PalmettoSmoke- I use a small amount of stubb's, then only large pieces of oak or pecan-let me know if you get it figured out.

PalmettoSmoke
04-08-2013, 07:08 AM
I keep both stacks open while getting up to temp. Once I'm up, I close off the second stack. I think that having larger exhausts is crucial. I'm going to call them today and see if I can bring the pit to them.

boiler93
04-08-2013, 11:29 AM
Talked to the mfg and he confirmed they are making the move to 5" exhaust which might extend the temp range 15-20 degrees but said the pit was designed to cook at 200. He said that if I brought it back he would exchange out the exhaust. I asked him to send me the new exhaust and I would pay for shipping vs the 10 hr round trip worth of gas I would spend. He said no problem! I"ll get the auto mechanic guys from the school I work at to weld it on for me. Ill keep you updated!

ButtBurner
04-08-2013, 11:53 AM
Talked to the mfg and he confirmed they are making the move to 5" exhaust which might extend the temp range 15-20 degrees but said the pit was designed to cook at 200. He said that if I brought it back he would exchange out the exhaust. I asked him to send me the new exhaust and I would pay for shipping vs the 10 hr round trip worth of gas I would spend. He said no problem! I"ll get the auto mechanic guys from the school I work at to weld it on for me. Ill keep you updated!

its only designed to go to 200f?

rexbbq
04-08-2013, 12:01 PM
I was just looking at the pics and I was wondering about the accuracy of those thermometers. Have you checked them with some boiling water to see if they are accurate. Also you may want to put a small oven thermometer on the grates to see what they are reading. I never trust a thermometer that I haven't checked the calibration on.

dwfisk
04-08-2013, 12:06 PM
Talked to the mfg and he confirmed they are making the move to 5" exhaust which might extend the temp range 15-20 degrees but said the pit was designed to cook at 200. He said that if I brought it back he would exchange out the exhaust. I asked him to send me the new exhaust and I would pay for shipping vs the 10 hr round trip worth of gas I would spend. He said no problem! I"ll get the auto mechanic guys from the school I work at to weld it on for me. Ill keep you updated!

:crazy:Boy, that is pretty amazing, I've been doin this a while and I thought 225*-250* was low-n-slow! If it is not just an excuse, it seems to me the mfg should at a minimum disclose that kind of info prior to making a sale. I bet the mod to get the 5x5 exhaust will significantly improve the draft, much more than +20*.

PalmettoSmoke
04-08-2013, 12:12 PM
Talked to the mfg and he confirmed they are making the move to 5" exhaust which might extend the temp range 15-20 degrees but said the pit was designed to cook at 200. He said that if I brought it back he would exchange out the exhaust. I asked him to send me the new exhaust and I would pay for shipping vs the 10 hr round trip worth of gas I would spend. He said no problem! I"ll get the auto mechanic guys from the school I work at to weld it on for me. Ill keep you updated!

That's odd, and sounds like an excuse. When I picked up my pit from them, they specifically told me to season it at 300+ degrees. I never made it that high!

boiler93
04-08-2013, 07:17 PM
Yeah I told him the same thing-"thats not how it was advertised" it was definitely an excuse. When asked why they decided to go to the 5" exhaust he gave me another excuse and said they were able to get them at a lower price instead of telling me they were making a design improvement. I hope the new exhaust will solve the problem because other than the temp issue i am very happy with the setup.

dwfisk
04-08-2013, 07:23 PM
Sound like you have a plan, sorry the mfg was so weird. If your buds in the auto shop can't get-r-done, we got a torch & a mig available. I'm pretty confident the larger exhaust will get the stars in alignment and I agree its a really good lookin pit.

boiler93
04-08-2013, 07:33 PM
Thanks for everyone's wealth of knowledge and support with my question. I will keep you updated. If anyone else with an A1 figures it out sooner please also post updates.

PalmettoSmoke
04-08-2013, 07:50 PM
boiler93,

I just sent you a PM.

mikeleonard81
04-08-2013, 09:37 PM
If this thing was designed for 200 I'm taking mine back! 275 is not to much to ask for in my opinion?? I got mine up to 300 when i seasoned it saturday but I had to take a leaf blower to the vent and after that I had to keep opening the fire box door to let it breath. I deffinatly didn't have it over filled either.

ButtBurner
04-09-2013, 04:56 AM
I am new to offsets so i am no expert

But another thing I noticed right away on this pit is that the firebox does not sit as low compared to the smoke chamber as mine, or other pits I have seen

I wonder if that has some affect also? I have always been told that since heat rises, its better to have the firebox low for better flow and to keep the heat from getting trapped in the upper part of the firebox

makes sense, although I dont know if its really an issue or not

Smokin'Butts
04-09-2013, 09:04 AM
As long as you have good airflow, no heat should be getting trapped in the firebox. BUT, with the undersized stacks on this smoker.....airflow I think is a serious issue

boiler93
04-09-2013, 09:10 AM
Lets hope the air flow correction fixes our problem! Stay tuned.

ButtBurner
04-09-2013, 09:13 AM
As long as you have good airflow, no heat should be getting trapped in the firebox. BUT, with the undersized stacks on this smoker.....airflow I think is a serious issue

I just question is since I have never seen a fire box mounted even with the smoke chamber before.

I thought they were mounted below the smoke chamber for better airflow and heat transfer, thats all

PalmettoSmoke
04-09-2013, 09:54 AM
I just got off the phone with the Custom Pits guys. They have not even gotten any of the 5-inch pipe in yet. They are looking at taking one of the stacks away, and just leaving a 5-inch stack by the firebox. I think I want to keep both stacks.

I found a welder here in Columbia that said he could do the work. I may just get him to provide the larger pipe as well.

boiler93
04-09-2013, 11:30 AM
Thanks for the update because i haven't gotten a price back on the shipping yet starting to think they were avoiding me like the plague.

PalmettoSmoke
04-09-2013, 11:45 AM
Thanks for the update because i haven't gotten a price back on the shipping yet starting to think they were avoiding me like the plague.

They are. He didn't seem happy to talk to me. That's why I've decided to just procure the parts elsewhere.

Also, look at this site below (measurements may not be exact). According to this, we need a 6" pipe at 20" long (I'll get exact measurements when I get home).

Link to BBQ Pit Calculator (http://feldoncentral.com/bbqcalculator.html?cc=36,60,0,0,0,0,61041.60,20347 .20&fb=24,20,24,0,0,11520.00,20347.20,56.6&ch=6,576.00,20.38&fi=0,0,6,34.56,1.22&fc=10.84,15.32,92.16)

PalmettoSmoke
04-09-2013, 11:46 AM
It's a shame. With the few modifications, this really is a nice cooker. However, I'm not sure I can recommend them to anyone...

boiler93
04-09-2013, 11:55 AM
If you find a good deal on the parts, please share

Smokin'Butts
04-09-2013, 11:57 AM
What additional mods if any are you thinking of making besides the stack?

PalmettoSmoke
04-09-2013, 12:22 PM
What additional mods if any are you thinking of making besides the stack?

Right now, just the stacks. I'll probably also go ahead and seal it using red silicone around the smoker door. And, just for my own personal preference, I'd like to add latches to the door.

PalmettoSmoke
04-09-2013, 12:26 PM
If you find a good deal on the parts, please share

Will do. I'm going to try to get the smoker to the welder today or tomorrow.

PalmettoSmoke
04-09-2013, 12:47 PM
I just spoke to a guy at Metal Supermarket (not sure if you have one there). He said that he could sell me 20" of 6" Schedule 40 pipe for a little over $28.00. I've never bought pipe before, so I don't really know if that's a good deal or not (or even what schedule 40 means)!

BBQ Bandit
04-09-2013, 02:17 PM
I just spoke to a guy at Metal Supermarket (not sure if you have one there). He said that he could sell me 20" of 6" Schedule 40 pipe for a little over $28.00. I've never bought pipe before, so I don't really know if that's a good deal or not (or even what schedule 40 means)!

Schedule 40 defines a particular pipe wall thickness based on diameter = .28" thick.

Ref: http://www.engineeringtoolbox.com/nominal-wall-thickness-pipe-d_1337.html

ButtBurner
04-09-2013, 02:19 PM
what is the thickness of the metal the smoke chamber is made of?

PalmettoSmoke
04-09-2013, 02:23 PM
Schedule 40 defines a particular pipe wall thickness based on diameter = .28" thick.

Ref: http://www.engineeringtoolbox.com/nominal-wall-thickness-pipe-d_1337.html

Cool. Thanks. I think that should be good enough for a smokestack. Don't you think?

PalmettoSmoke
04-09-2013, 02:31 PM
They are. He didn't seem happy to talk to me. That's why I've decided to just procure the parts elsewhere.

Also, look at this site below (measurements may not be exact). According to this, we need a 6" pipe at 20" long (I'll get exact measurements when I get home).

Link to BBQ Pit Calculator (http://feldoncentral.com/bbqcalculator.html?cc=36,60,0,0,0,0,61041.60,20347 .20&fb=24,20,24,0,0,11520.00,20347.20,56.6&ch=6,576.00,20.38&fi=0,0,6,34.56,1.22&fc=10.84,15.32,92.16)

Question for you all: Since there are 2 stacks, could that one 20" piece be cut in to two 10" stacks and achieve the same results? I would cook with one stack closed most of the time (since it is a reverse flow design).

BBQ Bandit
04-09-2013, 02:40 PM
Question for you all: Since there are 2 stacks, could that one 20" piece be cut in to two 10" stacks and achieve the same results? I would cook with one stack closed most of the time (since it is a reverse flow design).

As a R/f smoker - you need plenty of airflow... accomplished with a tall exhaust (known as draft).
Keep the 20" intact.

DownHomeQue
04-09-2013, 02:41 PM
I have 2 6 inch exhaust on my 250 gallon cooker.. it does good.. would definitely reccomend doing the same on yours to big is better than not enough.. because you can always close her down.. and i would do it!

PalmettoSmoke
04-09-2013, 02:42 PM
As a R/f smoker - you need plenty of airflow... accomplished with a tall exhaust (known as draft).
Keep the 20" intact.

That's what I thought. I'll make both stacks 20". Like I said, the one on the end is usually closed when I'm cooking. It would look funny with 2 different sized stacks.

DownHomeQue
04-09-2013, 02:42 PM
get a 40 inch pipe and make 2 20" 6" exhaust!

PalmettoSmoke
04-09-2013, 02:45 PM
get a 40 inch pipe and make 2 20" 6" exhaust!
Metal Supermarket will cut them any length I want. I'll get them to cut two 20" pipes. Then, hopefully the welder won't charge me an arm and a leg to put them on (I really need to learn to weld)!

ButtBurner
04-09-2013, 02:54 PM
Metal Supermarket will cut them any length I want. I'll get them to cut two 20" pipes. Then, hopefully the welder won't charge me an arm and a leg to put them on (I really need to learn to weld)!

how thick is the smoke chamber metal???

PalmettoSmoke
04-09-2013, 03:04 PM
how thick is the smoke chamber metal???

I'm not sure. I'm not at home right now. Does this make a difference in what I can use for the stacks?

ButtBurner
04-09-2013, 03:07 PM
I'm not sure. I'm not at home right now. Does this make a difference in what I can use for the stacks?

it might

I would try to get stacks that are close to the chamber in thickness since its a lot easier to weld the 2 together than 2 that are quite different. I would try to match the thickness of the stacks you already have.

A good welder will be able to do it but it would be good to know before you order stack material.

I just figured you would know, thats all.

PalmettoSmoke
04-09-2013, 03:11 PM
No problem. If I had to guess, I'd say 1/4" thick. Like I said earlier, I have no experience welding. I had no idea that it was easier to weld 2 things the same thickness together.

I may just take the smoker to the welder, and ask what he recommends.

ButtBurner
04-09-2013, 03:13 PM
No problem. If I had to guess, I'd say 1/4" thick. Like I said earlier, I have no experience welding. I had no idea that it was easier to weld 2 things the same thickness together.

I may just take the smoker to the welder, and ask what he recommends.

I think that would the best idea. You may take him something and then he suggests something else, might as well get his recommendation.

BBQ Bandit
04-09-2013, 03:50 PM
I think that would the best idea. You may take him something and then he suggests something else, might as well get his recommendation.

To add to that...if you develop a business relationship with a local welder/fabricator, try to barter BBQ with future welding jobs, yielding a win-win scenario.

ButtBurner
04-09-2013, 04:11 PM
To add to that...if you develop a business relationship with a local welder/fabricator, try to barter BBQ with future welding jobs, yielding a win-win scenario.

Oh yeah! welders (and mechanics) are good to know

glad I do both LOL ( I am a retired mechanic by trade)

jonboy
04-09-2013, 04:16 PM
What is the box on top of the firebox?
Is it a warmer? Does it have an exhaust?
jon

dwfisk
04-09-2013, 04:58 PM
Hey guys, just another option if you have any trouble sourcing tubing. I'm assuming all the discussion about 6 inch refers to round tubing. If round is OK, custom exhausts for big rigs are often made of 6 inch but it will be thinner wall, plenty for a smoker exhaust but whoever does the welding needs to be careful - it's not difficult just need to know what you are doing. I used exhaust tubing welded to my 1/4 thick tank and it works fine, its also comparatively cheap. Developing a relationship with the shop that will do the welding and listening to their recommendation is really solid advice.

boiler93
04-09-2013, 05:49 PM
What is the box on top of the firebox?
Is it a warmer? Does it have an exhaust?
jon

It's just a warming rack without intakes or exhaust

buttburnersbbq
04-09-2013, 06:50 PM
Metal Supermarket will cut them any length I want. I'll get them to cut two 20" pipes. Then, hopefully the welder won't charge me an arm and a leg to put them on (I really need to learn to weld)!

All you have to do is buy a flux core wire feed welder, watch a few you tube videos . Then you are on your way to welding .

dwfisk
04-09-2013, 06:53 PM
And get a pile of scrap steet - paractice, practice practice, then some more practice!

All you have to do is buy a flux core wire feed welder, watch a few you tube videos . Then you are on your way to welding .

ButtBurner
04-09-2013, 06:53 PM
All you have to do is buy a flux core wire feed welder, watch a few you tube videos . Then you are on your way to welding .


oh sure

dont forget he will have to remove the old stack, cut a hole for a new one, fab up an elbow or whatever it may need and weld it on his brand new smoker and make it look half way decent

yeah go watch some u tube and have at it LOL

J&B'sBBQ
04-09-2013, 07:34 PM
We got a pit a few weeks ago from the same guys and we're loving it, but still figuring it all out. The first cook took us 2hrs to get it up to temp and we struggled with getting it above 230 degrees according to the door thermo. The 2nd cook we were able to get it closer to 240 and a few weeks ago we hit 270. With that being said, the last time I took a wireless thermo and put it in different places on the two racks and found that my internal temps were WAY hotter than the door thermo stated. We were up to 300 in the top left corner and running at the door thermo temp in the bottom right corner.

Have you checked the variance of temps inside the pit? The door thermo isn't always a great representation. Let me know how it works out though because we would like to get higher temps (or have the choice) and if Brad changes out your stacks I might contact him and see if they'll do ours as well.

J&B'sBBQ
04-09-2013, 07:37 PM
No problem. If I had to guess, I'd say 1/4" thick. Like I said earlier, I have no experience welding. I had no idea that it was easier to weld 2 things the same thickness together.

I may just take the smoker to the welder, and ask what he recommends.

It is 1/4" thick. We have the same smoker.

boiler93
04-09-2013, 08:52 PM
Have you checked the variance of temps inside the pit? The door thermo isn't always a great representation. Let me know how it works out though because we would like to get higher temps (or have the choice) and if Brad changes out your stacks I might contact him and see if they'll do ours as well.

I bought 2 oven thermometers this weekend and the left side was about +20 h than then the door thermo and -20 on the right side.

mikeleonard81
04-09-2013, 09:32 PM
Thanks for all the info gentleman!! I can't wait till the weekend to try mine out for the first time:clap:

PalmettoSmoke
04-11-2013, 10:12 AM
Quick Update:

I've sources the 6" pipe. I'm getting them to cut me two 21" pieces. The welder said that he can do the work while I'm there. I'm going to try to sneak out of work early today or tomorrow to get it done.

I'll post the results (with pics) as soon as it's done.

J&B'sBBQ
04-11-2013, 11:50 AM
I bought 2 oven thermometers this weekend and the left side was about +20 h than then the door thermo and -20 on the right side.

I am so glad you checked! We see similar variances inside our pit too. I did a full day cook on a couple butts and moved my thermo all over the pit to find the differences in the temps so I could track it for cooks. I know exactly where to put different cuts now :).

J&B'sBBQ
04-11-2013, 11:51 AM
Quick Update:

I've sources the 6" pipe. I'm getting them to cut me two 21" pieces. The welder said that he can do the work while I'm there. I'm going to try to sneak out of work early today or tomorrow to get it done.

I'll post the results (with pics) as soon as it's done.

PLEASE let us know! Is it going to be pretty reaonsable in the cost department? If they only have 5" pipe to swap out for, I would almost be more willing to just go with the 6" and spend the money so it is correct...just havent decided yet for sure.

PalmettoSmoke
04-11-2013, 12:13 PM
PLEASE let us know! Is it going to be pretty reaonsable in the cost department? If they only have 5" pipe to swap out for, I would almost be more willing to just go with the 6" and spend the money so it is correct...just havent decided yet for sure.

JPS11 linked me to a forum post on another site where this exact discussion took place back in December. It looks like a 6" pipe extended down to just above the top grate and 20" or so above the smoker solved his issues. He didn't replace the 3" exhaust on the grill end (since it's pointless anyway). Another mod that they were talking about is to lower the grate in the firebox to only about 3"-4" above the floor. I'm not at my house to do measurements right now, but I'm thinking a 36" pipe would get the job done.

Between the pipe and the welder's labor, I'm coming in at less that $150 if I just replace the one exhaust. I'll probably jsut et the welder to either cut the other exhaust off and patch the hole, or just leave it there and leave it closed.

I'm not sure about the rules for posting links to other forums here, so I'll send you the link in a PM if you're interested in reading it.

ButtBurner
04-11-2013, 01:48 PM
I saw that thread saga

its a pretty interesting read.

J&B'sBBQ
04-12-2013, 08:13 AM
I spoke to the guys at Custom Pits yesterday and did have a pretty good conversation with them.

They did admit to me that there are flow issues if you're wanting to achieve higher temps, and are changing those for their new pits. They said they will replace the pipes for me (for free). Also, I brought up the shelf placement in the firebox being a bit high (6" off the floor) and he said they will gladly lower that for us to whatever level we want. I am not sure if we should go wtih 2" or 3" off the bottom of the box but it would gain us at least 3" of room in there.

I will also say that we've been using this pit every weekend for the last month and 1/2, and as you work with it (as any smoker) it becomes easier to adjust and achieve the temperatures you want. We have had the door gauge up to 265-270 which means the upper right hand corner was reaching about 290. It CAN get to the higher temps, it just takes a lot of practice and work to get it there.

I'll let y'all know how it goes with them swapping out the pipes and lowering the rack.

PalmettoSmoke
04-12-2013, 08:17 AM
Beth,

Thanks for the update. I'm glad that they have admitted the fault, and are replacing the stacks for free. I have chosen to get my own replacements because I live too far away. I'm only going to replace the exhaust closest to the firebox, as the other exhaust serves no purpose anyway.

As far as the grate in the firebox goes, I'd go 3" or 4" off the floor. You want to leave room for the ash to pile up and not smother your fire.

dwfisk
04-12-2013, 09:03 AM
"Also, I brought up the shelf placement in the firebox being a bit high (6" off the floor) and he said they will gladly lower that for us to whatever level we want. I am not sure if we should go wtih 2" or 3" off the bottom of the box but it would gain us at least 3" of room in there."

If it helps any, the firebox for my offset is 24" deep X 24 high X 22 wide and I have my firegrate about 2-1/2 inches off the floor. When I do a long cook, say 12-14 hours, I get about 1-1/2 inch of ash (burning hickory splits). I think 2-3 inches would be plenty. Best of luck!

PalmettoSmoke
04-12-2013, 09:06 AM
"Also, I brought up the shelf placement in the firebox being a bit high (6" off the floor) and he said they will gladly lower that for us to whatever level we want. I am not sure if we should go wtih 2" or 3" off the bottom of the box but it would gain us at least 3" of room in there."

If it helps any, the firebox for my offset is 24" deep X 24 high X 22 wide and I have my firegrate about 2-1/2 inches off the floor. When I do a long cook, say 12-14 hours, I get about 1-1/2 inch of ash (burning hickory splits). I think 2-3 inches would be plenty. Best of luck!

That's good to know. Thanks for the info.

boiler93
04-12-2013, 09:17 AM
They must have made that mod on mine before i bought it because if you go back and look at my pics my grate in the firebox is about 3 inches. Reading what everyone has posted here and the link that JPS11 sent out I should have my problem solved by swapping out the exhaust to a 6 inch. Thanks to all that helped!

PalmettoSmoke
04-12-2013, 09:20 AM
They must have made that mod on mine before i bought it because if you go back and look at my pics my grate in the firebox is about 3 inches. Reading what everyone has posted here and the link that JPS11 sent out I should have my problem solved by swapping out the exhaust to a 6 inch. Thanks to all that helped!

I'm taking my smoker to the welder on my lunch break. I'll post pictures of the new exhaust. I won't be able to cook anything until next weekend though. I've got a busy day doing family stuff tomorrow, and I leave to go out of town for work on Sunday.

J&B'sBBQ
04-12-2013, 10:59 AM
I will go with 2.5-3" of depth there then. Again, they were super helpful to me (not sure why they were not with others) and I will let everyone know how it goes. We'll be taking it to them on the 21st since we're competing next weekend in Cornelia and I do not want to make any mods to it right before the competition :).

TuscaloosaQ
04-12-2013, 12:15 PM
like I said way earlier in the post things were undersized intakes firebox and piping. I always wondered how they sold those for the price they do now I understand fully. One question how thick is the material on tha cooker is the firebox out of 1/4 inch sure don't look like it. I build em everyday and am not being critical I hope you get it worked out!!!! If that cooker is only designed to run 200 degrees..... That is truly sad !!!!! Every firebox we build is around 110&#37; of what it should be by calculations.... It's not because it needs that much fire it is about 02 and flow a well managed smaller fire with a good coal bed is better no need to over fire and wear the firebox out needlessly in my opinion. I had to learn this and now I call it the gospel

PalmettoSmoke
04-12-2013, 02:59 PM
I just got home from the welder. This is a big pipe! I may do a test burn tonight if I have time. For now, here are some pics I took at the welders:

About 21" above the cook chamber
http://i.imgur.com/UPtwaDv.jpg?1 (http://imgur.com/UPtwaDv)

The inside of the chamber
http://i.imgur.com/QfVBqor.jpg?1 (http://imgur.com/QfVBqor)

I left the other (3" pipe) exhaust on for now. I may have them cut it off (or even with the grill) in the future. It looks a little silly.

dwfisk
04-12-2013, 04:45 PM
Looks good & I'm thinkin this will fix the problem. Get yourself a #10 tin can to keep the rain & kritters out.
:clap2:
I just got home from the welder. This is a big pipe! I may do a test burn tonight if I have time. For now, here are some pics I took at the welders:

About 21" above the cook chamber
http://i.imgur.com/UPtwaDv.jpg?1 (http://imgur.com/UPtwaDv)

The inside of the chamber
http://i.imgur.com/QfVBqor.jpg?1 (http://imgur.com/QfVBqor)

I left the other (3" pipe) exhaust on for now. I may have them cut it off (or even with the grill) in the future. It looks a little silly.

PalmettoSmoke
04-12-2013, 07:43 PM
Looks good & I'm thinkin this will fix the problem. Get yourself a #10 tin can to keep the rain & kritters out.
:clap2:

Thanks. I hope this works! The welder cut a piece of scrap plate for a baffle (or whatever you call it). He welded a bolt to the exhaust and put the plate on there to cover the top.

1MoreFord
04-12-2013, 09:00 PM
Thanks. I hope this works! The welder cut a piece of scrap plate for a baffle (or whatever you call it). He welded a bolt to the exhaust and put the plate on there to cover the top.

Even with a damper it's still better to cover the stack with a can or bucket.

PalmettoSmoke
04-12-2013, 09:01 PM
Even with a damper it's still better to cover the stack with a can or bucket.

Can you explain why?

boiler93
04-12-2013, 10:14 PM
I'm going to have two holes drilled for probe access next week when I have new exhaust added. Drawing upon everyone's experience, is there a preferred location?

boiler93
04-12-2013, 10:15 PM
Looks good Palmetto!!

PalmettoSmoke
04-12-2013, 11:03 PM
I'm going to have two holes drilled for probe access next week when I have new exhaust added. Drawing upon everyone's experience, is there a preferred location?

That sounds like a good idea. I'd go right under the door.

jwmiser85
04-12-2013, 11:49 PM
Glad to see the issues being worked out. I ordered a Horizon pit..hope it's good to go and I dont have to go through this.

mikeleonard81
04-13-2013, 01:30 AM
I just ordered door seal and plan on droping the grate in the fire box to 3". I'm looking into getting a bbq guru for the back side of the fire box instead of installing another damper. Does anyone have experience with a guru? And do you think this will help with the air flow problem? Any and all advice is welcome :) Thanks!!

PalmettoSmoke
04-13-2013, 09:38 AM
Glad to see the issues being worked out. I ordered a Horizon pit..hope it's good to go and I dont have to go through this.

I've heard good things about Horizon pits. Hope you enjoy it!

I just ordered door seal and plan on droping the grate in the fire box to 3". I'm looking into getting a bbq guru for the back side of the fire box instead of installing another damper. Does anyone have experience with a guru? And do you think this will help with the air flow problem? Any and all advice is welcome :) Thanks!!

I'm adding some seal to my door today. Regardless of the Guru or not, I think you're going to have to get a larger exhaust.

1MoreFord
04-13-2013, 12:40 PM
That sounds like a good idea. I'd go right under the door.

Unless your damper actually covers the stack like a cap with sides coming down over the stack (or you cover the entire cooker with a water proof cover) you will still get some water down the stack.

boiler93
04-17-2013, 08:45 PM
http://i1325.photobucket.com/albums/u627/puboiler93/photocopy7_zps8632080f.jpg (http://s1325.photobucket.com/user/puboiler93/media/photocopy7_zps8632080f.jpg.html)

Added a 6" exhaust today and couldn't wait to get it home and fire her up. Works like a charm! no problem getting up past 300 and all of a sudden I don't have the heat and smoke bellowing from the door. THANKS FOR THE HELP!

NEXT QUESTION: Instead of throwing away the 3" stack I added it to my warming box. As of right now the warming box receives indirect heat from being on top of the fire box. If I want to turn the warming box into a vertical smoker for smaller cooks what ideas do you guys have have for an opening between the two?

J&B'sBBQ
04-17-2013, 09:44 PM
Looks great guys!! I'm excited to get my pit up to them to have them fix it now.

@boiler93; I was thinking that the larger exhaust would help fix all the smoke leaking because now the smoke has a logical place to go, and I am glad to hear that it is working as it should.

I'll make sure to post pics as well when we get ours fixed up.

PalmettoSmoke
04-18-2013, 12:07 AM
http://i1325.photobucket.com/albums/u627/puboiler93/photocopy7_zps8632080f.jpg (http://s1325.photobucket.com/user/puboiler93/media/photocopy7_zps8632080f.jpg.html)

Added a 6" exhaust today and couldn't wait to get it home and fire her up. Works like a charm! no problem getting up past 300 and all of a sudden I don't have the heat and smoke bellowing from the door. THANKS FOR THE HELP!

NEXT QUESTION: Instead of throwing away the 3" stack I added it to my warming box. As of right now the warming box receives indirect heat from being on top of the fire box. If I want to turn the warming box into a vertical smoker for smaller cooks what ideas do you guys have have for an opening between the two?

Glad it's working! I plan to cook this weekend when I get home from travel.