OK so I think I wasted close to $100 dollars in this fan :'(. It does move air around but not nearly enough to keep the temps even from top to bottom. I don't even have any racks in the smoker so there is nothing interfering with the air movement or lack there of ;D. Same results no matter where i put the probes. I checked the probes with boiling water and they are accurate :). I have a 25 degree difference :o >:(. Its in the garage so there is no wind and the temp outside is 71. The dual 500 mod is working fine with the PID. Hovering between 224-226. Set at 225F.
For those of you that are having great results, what do you think is going on with those of us who are not having the same luck ???. I am even willing to try the dual fan blades inside, back to back to see if it makes a difference. I read a thread on here were it was done. Said it pushes up to 25% more air. JZ is going to try it and hopefully post results.
Gonna post pics with my phone to show how it is pushing air. give me a sec, I'm on the laptop and gonna upload them from my phone. just in case some one reads this while I'm getting the pics. ;D
(http://img.tapatalk.com/4c1f4313-20c2-9786.jpg)
Here you can see the fan off and the tissue straight down. The probe is to the left of center and actually hanging between the v tray and where the bottom tray would be. The fan is not blowing straight at it. The top probe is down the vent also and its hanging right about where the first tray would be. (not shown on this pic)
(http://img.tapatalk.com/4c1f4313-20f1-a448.jpg)
Here the fan is on and the tissue although hard to tell, its actually moving and the bottom edge is right at the edge of the v-tray
(http://img.tapatalk.com/4c1f4313-267a-3b2a.jpg)
So here are the latest temps. I closed the vents on the v-tray towards the back. All but the one closest to the drain hole. Left the
Ones toward the front of the smoker open. Think read this from viper125 post.
(disregard the temp on the maverick food side it's 13 degrees off and sitting on the concrete. The oven probe reads perfect during water boil test.)
The ET732 is getting the RTV silicone treatment. ;D
Sent from my iPhone using Tapatalk
Same thing here. I didn't check temp variations inside the chamber with thermometers but the results were obvious on the meat.
I am going to stack the blades if there is room and will let you know what I find. But I don't think this will do the trick.
Mike, perhaps the higher temps that you are running it might be adding to the difference between top and bottom. Obviously that element is very hot and stays very hot.
Have you tried it at a low temp like 130 dgrees and checked to see what it was? I don't go over 170 with my OBS and have had no problems thus far.
I'm kinda thinking out loud, that's all.
What's the cfm rating on the fan blades you have? When I was shopping on the online Grainger site I remember they had a 2" blade with a 30cfm and a 2.5" with a 45cfm rating. If you're using the smaller blade you'd get a 50% airflow increase by going to the slightly larger size.
I bought one of those little fans also and was very disappointed in the performance so i did a mod myself. Not that i recommend anyone going to the extreme I did but I can tell you I now have a very effective fan with good air flow and constant temps through out the smoker.
(https://lh3.googleusercontent.com/-VAtrqOYmGHE/T0FAh_520fI/AAAAAAAACAo/Fxhpm7aZTHo/s720/DSC_0058.JPG)
(https://lh3.googleusercontent.com/-Pf2Ca4TWMjk/T0FAu4S2g7I/AAAAAAAACA4/PcGPXgnbXAg/s720/DSC_0059.JPG)
(https://lh5.googleusercontent.com/-2dYQOXPq_d4/T0FAhZRqd-I/AAAAAAAACAk/MU_AudVIbDc/s720/DSC_0060.JPG)
(https://lh4.googleusercontent.com/-SYbto5cyG2U/T0FByKEKGlI/AAAAAAAACBA/1uxNvm4JIEE/s720/DSC_0061.JPG)
Quote from: Sam3 on March 09, 2012, 08:43:18 AM
Mike, perhaps the higher temps that you are running it might be adding to the difference between top and bottom. Obviously that element is very hot and stays very hot.
Have you tried it at a low temp like 130 dgrees and checked to see what it was? I don't go over 170 with my OBS and have had no problems thus far.
Sam, now that i think about it, yes, when I was making sticks, the temps were even and or alot closer together when I was starting at 130. Even took a pic of it. When i got to 170 to finish, the temps were about 10 off from top to bottom. Ive been at this all morning trying different things. I was even going to buy an extra fan blade here locally for around $4 till I took my fan off and tried fitting both blades on the shaft inside just to see if they would fit. NOT >:(!! I put both blades on while the fan was off the smoker to see if I could tell the difference in flow. Cant really tell, thats not to say that once its inside mounted it will make a difference. JZ is also tinkering with his. Been PM'ing with him this morning. Hopefully he has better luck. :)
Quote from: TedEbear on March 09, 2012, 08:47:06 AM
What's the cfm rating on the fan blades you have? When I was shopping on the online Grainger site I remember they had a 2" blade with a 30cfm and a 2.5" with a 45cfm rating. If you're using the smaller blade you'd get a 50% airflow increase by going to the slightly larger size.
Problem is that I dont thing the bigger blade will fit. I will most likely hit the v tray, its already a close fit mounted using the template that came with it. It sits right between the bottom most tray and v tray. Dont want to spend the money on another then it will not fit :) ;)
Thanks for the reply. :)
Quote from: devo on March 09, 2012, 09:02:16 AM
I bought one of those little fans also and was very disappointed in the performance so i did a mod myself. Not that i recommend anyone going to the extreme I did but I can tell you I now have a very effective fan with good air flow and constant temps through out the smoker.
(https://lh3.googleusercontent.com/-VAtrqOYmGHE/T0FAh_520fI/AAAAAAAACAo/Fxhpm7aZTHo/s720/DSC_0058.JPG)
(https://lh3.googleusercontent.com/-Pf2Ca4TWMjk/T0FAu4S2g7I/AAAAAAAACA4/PcGPXgnbXAg/s720/DSC_0059.JPG)
(https://lh5.googleusercontent.com/-2dYQOXPq_d4/T0FAhZRqd-I/AAAAAAAACAk/MU_AudVIbDc/s720/DSC_0060.JPG)
(https://lh4.googleusercontent.com/-SYbto5cyG2U/T0FByKEKGlI/AAAAAAAACBA/1uxNvm4JIEE/s720/DSC_0061.JPG)
Where did you get that. I saw the thread where you commented on this saying that it wasnt pretty but it work. That doesnt look bad at all. LIL paint on there and BAM! coustom looking job. ;D
Quote from: mikecorn.1 on March 09, 2012, 09:20:06 AM
Quote from: Sam3 on March 09, 2012, 08:43:18 AM
Mike, perhaps the higher temps that you are running it might be adding to the difference between top and bottom. Obviously that element is very hot and stays very hot.
Have you tried it at a low temp like 130 dgrees and checked to see what it was? I don't go over 170 with my OBS and have had no problems thus far.
Sam, now that i think about it, yes, when I was making sticks, the temps were even and or alot closer together when I was starting at 130. Even took a pic of it. When i got to 170 to finish, the temps were about 10 off from top to bottom. Ive been at this all morning trying different things. I was even going to buy an extra fan blade here locally for around $4 till I took my fan off and tried fitting both blades on the shaft inside just to see if they would fit. NOT >:(!! I put both blades on while the fan was off the smoker to see if I could tell the difference in flow. Cant really tell, thats not to say that once its inside mounted it will make a difference. JZ is also tinkering with his. Been PM'ing with him this morning. Hopefully he has better luck. :)
hey mc did you happen to look at the post by Docz, i believe he had to add a piece of
dowel and then siliconed the 2 fans together to make them fit on orginal shaft,
i am thinking that is because like you said the 2 won't fit on orginal shaft alone.
just another thought for you
Quote from: mikecorn.1 on March 09, 2012, 09:20:06 AM
Quote from: Sam3 on March 09, 2012, 08:43:18 AM
Mike, perhaps the higher temps that you are running it might be adding to the difference between top and bottom. Obviously that element is very hot and stays very hot.
Have you tried it at a low temp like 130 dgrees and checked to see what it was? I don't go over 170 with my OBS and have had no problems thus far.
Sam, now that i think about it, yes, when I was making sticks, the temps were even and or alot closer together when I was starting at 130. Even took a pic of it. When i got to 170 to finish, the temps were about 10 off from top to bottom. Ive been at this all morning trying different things. I was even going to buy an extra fan blade here locally for around $4 till I took my fan off and tried fitting both blades on the shaft inside just to see if they would fit. NOT >:(!! I put both blades on while the fan was off the smoker to see if I could tell the difference in flow. Cant really tell, thats not to say that once its inside mounted it will make a difference. JZ is also tinkering with his. Been PM'ing with him this morning. Hopefully he has better luck. :)
It also helped with the circulation of the smoke when I was making sticks and such. Everything had a uniform color on it.
Maybe because of the higher heat, you need something larger that will move more air like devo posted.
Quote from: Sam3 on March 09, 2012, 09:34:29 AM
Quote from: mikecorn.1 on March 09, 2012, 09:20:06 AM
Quote from: Sam3 on March 09, 2012, 08:43:18 AM
Mike, perhaps the higher temps that you are running it might be adding to the difference between top and bottom. Obviously that element is very hot and stays very hot.
Have you tried it at a low temp like 130 dgrees and checked to see what it was? I don't go over 170 with my OBS and have had no problems thus far.
Sam, now that i think about it, yes, when I was making sticks, the temps were even and or alot closer together when I was starting at 130. Even took a pic of it. When i got to 170 to finish, the temps were about 10 off from top to bottom. Ive been at this all morning trying different things. I was even going to buy an extra fan blade here locally for around $4 till I took my fan off and tried fitting both blades on the shaft inside just to see if they would fit. NOT >:(!! I put both blades on while the fan was off the smoker to see if I could tell the difference in flow. Cant really tell, thats not to say that once its inside mounted it will make a difference. JZ is also tinkering with his. Been PM'ing with him this morning. Hopefully he has better luck. :)
It also helped with the circulation of the smoke when I was making sticks and such. Everything had a uniform color on it.
Maybe because of the higher heat, you need something larger that will move more air like devo posted.
TRUE. :) ;)
Quote from: mikecorn.1 on March 09, 2012, 09:26:14 AM
Problem is that I dont thing the bigger blade will fit. I will most likely hit the v tray, its already a close fit mounted using the template that came with it.
Well, it would only be 1/4" more at the top and bottom. I didn't think the tolerances were that tight.
I have a Dayton fan kit sitting in my basement that I bought from Grainger - I just haven't installed it yet. I think I bought the 2.5" blades for it. I noticed just now that they have a 3" blade with a 60cfm rating. I'll check the clearance when I get home this afternoon.
Ok I put the second blade on and fired it up. I had 3 temp gauges going 1 at the top, Auber PID in the middle and third one just above the vpan (about 3"). I set the PID to 200* and here are the results.
The middle and top readings stayed within 2 degrees of each other. The bottom one was different story. The temp difference between it and the other 2 was around 25* - 30* while the box was heating up and when it got to the set temp the difference started to drop. By the time the whole thing settled in for awhile the temp difference was around 16* - 18*. I did not check the temps at the back or front of the box and will go and move the probes to see if that makes a difference. NOTE THAT THIS IS WITHOUT A LOAD.
My conclusion is that the more heat that is required to maintain the set temp the more the variance will be. Once the set temp has been achieved it will take less energy to maintain it it and therefore the internal temps will be more even. Adding a large load of meat is going to mean more heat is required and as the temp differences will be greater because the elements will be on longer. Also as Sam3 pointed out the temp variations will be less at lower temps because less energy is required to maintain the lower temps.
I like Devos solution but not sure I want to take that step yet. Might just carry on with the current setup, since it is already installed.
Quote from: JZ on March 09, 2012, 09:39:33 AM
Ok I put the second blade on and fired it up. I had 3 temp gauges going 1 at the top, Auber PID in the middle and third one just above the vpan (about 3"). I set the PID to 200* and here are the results.
The middle and top readings stayed within 2 degrees of each other. The bottom one was different story. The temp difference between it and the other 2 was around 25* - 30* while the box was heating up and when it got to the set temp the difference started to drop. By the time the whole thing settled in for awhile the temp difference was around 16* - 18*. I did not check the temps at the back or front of the box and will go and move the probes to see if that makes a difference. NOTE THAT THIS IS WITHOUT A LOAD.
My conclusion is that the more heat that is required to maintain the set temp the more the variance will be. Once the set temp has been achieved it will take less energy to maintain it it and therefore the internal temps will be more even. Adding a large load of meat is going to mean more heat is required and as the temp differences will be greater because the elements will be on longer. Also as Sam3 pointed out the temp variations will be less at lower temps because less energy is required to maintain the lower temps.
I like Devos solution but not sure I want to take that step yet. Might just carry on with the current setup, since it is already installed.
By what you just posted, I am not adding a second blade, I have the exact same results with one blade. We might as well have been doing all the testing on cloned bradleys (I mean same readings, no joking) :o
Moved the probes as follows. Bottom one moved closer to the back wall and still just above the vtray. Middle one (PID) stayed in the middle of the box. The top one moved closer to the front and still near the top of the box. This time the temp differences were more pronounced. The difference between the bottom and the middle were up to 40* while the box was coming up to temp and the difference between the middle and top front were up to 10*.
Once everything settled in the temp differences between the bottom and other 2 was around 10*. Again this is with an empty box.
I am doing some stick tomorrow so will get some real world results and let you know how it goes.
Quote from: JZ on March 09, 2012, 10:17:23 AM
Moved the probes as follows. Bottom one moved closer to the back wall and still just above the vtray. Middle one (PID) stayed in the middle of the box. The top one moved closer to the front and still near the top of the box. This time the temp differences were more pronounced. The difference between the bottom and the middle were up to 40* while the box was coming up to temp and the difference between the middle and top front were up to 10*.
Once everything settled in the temp differences between the bottom and other 2 was around 10*. Again this is with an empty box.
I am doing some stick tomorrow so will get some real world results and let you know how it goes.
Good luck, will checking in to see. I was constistant at 130 and as I went on to 170 it kep getting further apart. At 170 it was 10 degree different. This on on my last snack stix smoke. With the fan on. Stick hanging with plenty of space in between especially in the middle, so that the air could circulate. 5 lbs.
(http://img.tapatalk.com/4c1f4313-2924-c08f.jpg)
Mike, if I understand your post correctly, the fan is blowing towards the door. If that's the case, there are others that have reversed the rotation of the motor so the fan draws towards the back of the cabinet. The fan is set about 1/2" away from the cabinet back. Reportedly, the circulation and temps are more even.
Quote from: Salmonsmoker on March 09, 2012, 05:44:25 PM
Mike, if I understand your post correctly, the fan is blowing towards the door. If that's the case, there are others that have reversed the rotation of the motor so the fan draws towards the back of the cabinet. The fan is set about 1/2" away from the cabinet back. Reportedly, the circulation and temps are more even.
Yes towards the front. I read somewhere on how to reverse it. Anyone know where the thread is? :)
Sent from my iPhone using Tapatalk
I put the 2.5 inch fan blade on and haven't had any problems. I only checked temp difference once and it wasn't way off, 3-4 degrees. I had to notch out the v-tray and it clears the 1st rack. It doesn't seem like it is pushing alot of air, but I don't have to rotate racks and it pretty much cooks even top to bottom. Hers's a couple pictures. Hope this helps.
(http://i1087.photobucket.com/albums/j466/kickedback1/DSC04760.jpg)
(http://i1087.photobucket.com/albums/j466/kickedback1/DSC04761-1.jpg)
Quote from: kickedback on March 09, 2012, 06:32:37 PM
I put the 2.5 inch fan blade on and haven't had any problems. I only checked temp difference once and it wasn't way off, 3-4 degrees. I had to notch out the v-tray and it clears the 1st rack. It doesn't seem like it is pushing alot of air, but I don't have to rotate racks and it pretty much cooks even top to bottom. Hers's a couple pictures. Hope this helps.
(http://i1087.photobucket.com/albums/j466/kickedback1/DSC04760.jpg)
(http://i1087.photobucket.com/albums/j466/kickedback1/DSC04761-1.jpg)
This is the second time I've read about the 2.5". Kinda figured that it wouldn't fit in place of where the 2" is without cutting something. Yep, that's the same place mine is. Did you center the hole for the 2" and replace with the 2.5"? So you didn't have to cut the tray, just the V-tray? What temps where you looking at that were even (2-3 off)? Thanks for the info BTW :)
Sent from my iPhone using Tapatalk
Mike
I originally reversed mine to pull air to the back of the cabinet. This cased even more heat at the back of the cabinet. I reversed the motor back to run the fan blowing the air towards the door and I had much better results.
Here's a few things to look at:
- make sure the fan is spaced away from the back wall as far as possible. If the fan blade is right up against the wall it will have no intake air. Mount the collar of the fan towards the back of the cabinet, this will help get the blade as far as possible away from the wall.
- I'm not sure you are using the same blade that I am but I saw a good improvement on mine and it's been that way for a number of years. Is it perfect... No, but it's vastly improved.
- Tweak the openings in the V-Pan. Slightly open the front half of the vents and slightly close the rear vents. This helps move some of the heat to the front of the cabinet.
- As a last resort, try tweaking the pitch of your fan blade to increase the amount of air flow.
Mike
Quote from: Mr Walleye on March 09, 2012, 07:01:37 PM
Mike
I originally reversed mine to pull air to the back of the cabinet. This cased even more heat at the back of the cabinet. I reversed the motor back to run the fan blowing the air towards the door and I had much better results.
Here's a few things to look at:
- make sure the fan is spaced away from the back wall as far as possible. If the fan blade is right up against the wall it will have no intake air. Mount the collar of the fan towards the back of the cabinet, this will help get the blade as far as possible away from the wall.
- I'm not sure you are using the same blade that I am but I saw a good improvement on mine and it's been that way for a number of years. Is it perfect... No, but it's vastly improved.
- Tweak the openings in the V-Pan. Slightly open the front half of the vents and slightly close the rear vents. This helps move some of the heat to the front of the cabinet.
- As a last resort, try tweaking the pitch of your fan blade to increase the amount of air flow.
Mike
Holy Carp!! What, where you in my garage this morning with me hiding in a corner? LOL. Everything you just said, I did. Must be cause were Mike and great minds think alike!! ;D.
All joking aside, everything you said, I did. Not on thing did I miss from what you mentioned. The last thing I tried was the closing and opening of the vents on the v tray and it helped somewhat. I was doing all this at the 225 range. As stated by other members, it's easier to stabilize at lower temps. At least with this 2" blade.
Sent from my iPhone using Tapatalk
Quote from: rigstar on March 09, 2012, 09:32:57 AM
Quote from: mikecorn.1 on March 09, 2012, 09:20:06 AM
Quote from: Sam3 on March 09, 2012, 08:43:18 AM
Mike, perhaps the higher temps that you are running it might be adding to the difference between top and bottom. Obviously that element is very hot and stays very hot.
Have you tried it at a low temp like 130 dgrees and checked to see what it was? I don't go over 170 with my OBS and have had no problems thus far.
Sam, now that i think about it, yes, when I was making sticks, the temps were even and or alot closer together when I was starting at 130. Even took a pic of it. When i got to 170 to finish, the temps were about 10 off from top to bottom. Ive been at this all morning trying different things. I was even going to buy an extra fan blade here locally for around $4 till I took my fan off and tried fitting both blades on the shaft inside just to see if they would fit. NOT >:(!! I put both blades on while the fan was off the smoker to see if I could tell the difference in flow. Cant really tell, thats not to say that once its inside mounted it will make a difference. JZ is also tinkering with his. Been PM'ing with him this morning. Hopefully he has better luck. :)
hey mc did you happen to look at the post by Docz, i believe he had to add a piece of
dowel and then siliconed the 2 fans together to make them fit on orginal shaft,
i am thinking that is because like you said the 2 won't fit on orginal shaft alone.
just another thought for you
Thanks for the info. Im not gonna mess with the 2 blades after seeing what Jz posted. Probably try the 2.5" ;D
Sent from my iPhone using Tapatalk
Mike, sorry to see that you are having problems. I am using the blade that came with the kit. I have the coller where the set screw is pointing to the door. I don't seem to have any trouble with maintaining even temps. After reading this thread I went out and fired up the OBS with out a load as I wanted to season the new Amazin pellet burner I just got. Temp outside was 77. Got a probe in the top about inches down and put a rack in the bottom and have the cabinet probe hanging to just below the rack to the front. As the OBS started to heat up I never got more than 3 degrees difference between the top and bottom. I held the temp at 255 degrees for 2 hrs and maintained a 1 to 2 degree difference between the top and bottom. I sure hope that you can get it figured out. I am glad I did the mod and wish that I would have done it sooner.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0455.jpg)
Quote from: Sailor on March 09, 2012, 08:14:44 PM
Mike, sorry to see that you are having problems. I am using the blade that came with the kit. I have the coller where the set screw is pointing to the door. I don't seem to have any trouble with maintaining even temps. After reading this thread I went out and fired up the OBS with out a load as I wanted to season the new Amazin pellet burner I just got. Temp outside was 77. Got a probe in the top about inches down and put a rack in the bottom and have the cabinet probe hanging to just below the rack to the front. As the OBS started to heat up I never got more than 3 degrees difference between the top and bottom. I held the temp at 255 degrees for 2 hrs and maintained a 1 to 2 degree difference between the top and bottom. I sure hope that you can get it figured out. I am glad I did the mod and wish that I would have done it sooner.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0455.jpg)
Well F*#k me, I just dont understand what is going on with mine and other member that are having the same problem. Thanks for rubbing it in ;D ;D. Were did you place the bottom probe, was is directly in front of the fan flow or off to the side? Thanks for the post.
WTF - why is mine and Mikes so much different. We are all using the same fan blade, it turns at 3000 rpm, it is mounted at the back of the smoker and above the vtray. So how can we get such different results? I don't get it. :o
I did see that Sailor has his blade reversed to mine (ie the collar is at the front - which would mean that his blade is closer to the back of the smoker). But Mike (Mr Walleye) said he had better luck with his further away from the back wall.
I think I am going to hook up a leaf blower to this thing and be done with it. LOL ;D ;D
Quote from: JZ on March 09, 2012, 10:01:54 PMI think I am going to hook up a leaf blower to this thing and be done with it. LOL ;D ;D
LOL - you'll shoot those butts across the yard.
One last comment before I hit the road on a 5 hr road trip.
Does anyone think that it could possibly be the blade itself. They are so cheap and mass produced that they could be different as far as how they are angled or curved. Both the ones I have are slight different. When you look up close. Just a thought.
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The cabinet temp probe was placed just below the bottom rack in the corner between the door and side.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0456.jpg)
Meat probe was thru the top
(http://i36.photobucket.com/albums/e25/jcompton1/100_0457.jpg)
Fan blade placement
(http://i36.photobucket.com/albums/e25/jcompton1/100_0459.jpg)
Trying to show how I have the blade attached and how far off the wall.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0458.jpg)
Without a load the temp from start (77 degrees) to hold (255) never got above 3 degrees walking up. Last load of pistachios that I did I had a 20 degree difference from top to bottom. The longer they were in there the closer the temps got. I do my pistachios at 225 and still rotate them every hr. After 3 hrs the temp from top to bottom are close to 10 degrees apart. I will be doing a load of jerky this morning and will try to document the temp swings.
With the fan mod my cook times are a lot shorter.
One thing not talked about this small fan kit is if you live any where you get below zero temps the fan will not even turn till the cabinet temp gets high enough to warm it up. This was another reason I went with a bigger fan. The small fan works but there is room for improvement. Doing your own fan mod is a lot cheaper than the $100 kit. All the parts are available from wholesalers at a fraction of the price.
Quote from: devo on March 10, 2012, 05:59:55 AM
One thing not talked about this small fan kit is if you live any where you get below zero temps the fan will not even turn till the cabinet temp gets high enough to warm it up. This was another reason I went with a bigger fan. The small fan works but there is room for improvement. Doing your own fan mod is a lot cheaper than the $100 kit. All the parts are available from wholesalers at a fraction of the price.
I read that when you wrote it. I was having that issue also. Thought it was just mine. Good now that it's warming back up.
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Quote from: Sailor on March 10, 2012, 05:49:24 AM
The cabinet temp probe was placed just below the bottom rack in the corner between the door and side.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0456.jpg)
Meat probe was thru the top
(http://i36.photobucket.com/albums/e25/jcompton1/100_0457.jpg)
Fan blade placement
(http://i36.photobucket.com/albums/e25/jcompton1/100_0459.jpg)
Trying to show how I have the blade attached and how far off the wall.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0458.jpg)
Without a load the temp from start (77 degrees) to hold (255) never got above 3 degrees walking up. Last load of pistachios that I did I had a 20 degree difference from top to bottom. The longer they were in there the closer the temps got. I do my pistachios at 225 and still rotate them every hr. After 3 hrs the temp from top to bottom are close to 10 degrees apart. I will be doing a load of jerky this morning and will try to document the temp swings.
With the fan mod my cook times are a lot shorter.
Thanks for this post Sailor!! :)
Will play around with it when I get
Back home Wednesday.
Sent from my iPhone using Tapatalk
Mixing the jerky up and starting the OBS. Top and bottom 76 with no load.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0460.jpg)
Upper rack is in and this is the temp reading. Got a 8 degree difference.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0462.jpg)
2nd rack was made and put in. Got a 21 degree difference from top to bottom
(http://i36.photobucket.com/albums/e25/jcompton1/100_0463.jpg)
3rd rack is in and have 18 degree difference from top to bottom
(http://i36.photobucket.com/albums/e25/jcompton1/100_0464.jpg)
4 trays are in and letting it come back to temp.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0465.jpg)
Placement of my cabinet temp probe.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0466.jpg)
Just went out to check and I still have a 20 degree difference between top and bottom. I am not concerned with a 20 degree difference. I don't have a blast furnace for a smoker ;D My main objective was to get better smoke circulation and this itty bitty fan is doing that. It is keeping the back of the rack from over cooking and that is also good. I still rotate the racks. I know that it has cut the time way down to do snack stix and chubs. Tomorrow I will do a butt and give some feed back regarding temps. This is the 2nd load of jerky that I have done and I was happy on how the fan worked on the 1st try.
Quote from: devo on March 10, 2012, 05:59:55 AM
One thing not talked about this small fan kit is if you live any where you get below zero temps the fan will not even turn till the cabinet temp gets high enough to warm it up.
That wouldn't be a problem with mine since I store it in the basement until I'm going to use it.
On the blade sizes and different cfm ratings it appears that a 2.5" blade requires a bit of modification to the V-tray, from what I read. I was wondering if mounting it on the opposite wall across from the SG would be a good idea as far as being able to use a larger blade and thus more airflow without running into any interference. It wouldn't be pushing air toward the door but with the better air circulation I wonder if it would swirl everything around more and not really matter which direction the fan was pointing.
With the additional room in the "V" a shroud could also be added to keep the fan from blowing directly on the meat and drying it out. Someone else had a pic of one of these in their Bradley.
2" blade - 30 cfm
2.5" blade - 45 cfm
3" blade - 60 cfm
3.5" blade - 100 cfm
Here it is: Fan Shroud (http://www.susanminor.org/forums/showthread.php?186-Fan&p=848#post848)
(http://www.susanminor.org/users/Hab/Misc_Files/Other/Walleye_Fan/Circfanshield2.jpg)
what a boat of great info about the fan mod, i was on the fence before about
doing it, now i am really unsure :-\;
Tedebear - just curious if you mounted it facing the sg would you not run the risk
of potentially blowing smoke back out thru the sg, eventhough it is above the v-tray,
or do you think that would not be a problem?
just thinking if there is smoke going back thru there it would gum up smoke pushing
mechanism and slider
MC - I bought 6 of those fans and they all look pretty much the same to me. Besides when I stacked 2 blades on the inside of the smoker I was still getting big temp differences. I don't have the fan not working issue with the colder temps. I have been starting mine up at -5*C and it started just fine - but I didn't get the Grainger motor or Smoke and stuff kit. I got mine from a local supplier for $31.
I might get the 2 1/2" blade, a 3" blade and the 3" that pushes out 100cfm and give them a try. The way I mounted mine I will likely loose the use of the bottom rack but thats ok since I have 7 others. I would also have to trim the vtray for the 3" and probably the 2 1/2".
Well I am off to start some sticks and will let you know how that works on a separate thread.
Cool. Hurry up before I get back home. Lol. :)
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I ain't no rocket scientist and don't have any engineering schoolin either. :o I am thinking that we may be expecting too much from the fan mod and the Bradley. The Bradley 4 rack has roughly 3 cubic feet inside. The fan blade is rated at roughly 30 cfm. We should be turning the air over 30 times per min. Now you put meat in and the meat is going to absorb heat. You got moisture in the meat that is going to absorb and evaporate and cool the inside. The element is at the bottom and the cool evaporated moisture is being drawn up and out the top vent. I would think that this is going to really affect the temps inside the cabinet. The reason that I did the fan mod is I wanted to get the heat off the back of the unit and to circulate the smoke for a more even smoke. The iddy biddy fan is doing what I wanted. ;D
I am a thinkin that if we want even temps through out the cabinet with a load then a much larger fan set up is needed. When I get around to building a proofer smoker I will put ductwork on the outside to draw heat from the bottom and channels between each rack so that each rack is receiving equal amounts of heat.
For now I just don't see the need to have the temps be critically equal at every point in the smoker. When I hang snack stixs I get closer temps because the meat is hanging vertical and the heat can move around. I still get swings from top to bottom but I am not burning or drying out the bottom waiting for the top of the stixs to get up to IT. I can now do a 10 pound load of hanging stixs in a shorter amount of time than what I was doing a load of 5 pounds of stixs. Fan mod is responsible for this. The smoke on the stixs is more even and the fan mod is responsible for this. This is a good thing.
I do 3 pound loads of pistachios and rotate every hour and have no over roasted nuts. Before the mod I would always have over roasted nuts to the back of the rack. The fan mod evened out the heat enough that they roast even. I am very happy about that.
Never did jerky before the fan mod so I am not able to compare. What I can say is that I am getting a very even smoke on the jerky and not over cooking the rear of the racks. I am still rotating.
I have done lots of brisket and butts in the Bradley before the mod but none since the mod. I will be doing a Butt tonight for tomorrow's dinner and will be able to provide feedback then.
I guess the bottom line is the "I" am very happy with the mod and would do it again in a heartbeat. It is doing what I wanted which is to get the heat off the back and to circulate the smoke. Regardless of having equal temps at all times at every point in the cabinet my smokes are coming out better and taking less time. ;D
It has been 1 hour since the smoke has stopped rolling and I have turned the SG off. My temps are now starting to narrow. The probes are still in the same place. I now have a 13 degree difference compared to a 20 plus degree difference. I don't know if the heat from the generator has anything to do with this or if the moisture in the meat is being reduced so the heat is being more evenly distributed.
(http://i36.photobucket.com/albums/e25/jcompton1/100_0468.jpg)
MC - I won't have any results for the bigger fan blades and still not sure if I will do it. Depends on how things turn out today with my sticks. If I decide to get the bigger blades it will be 2 to 3 weeks before my local Grainger store will get them in. At least that is what it took to get the last ones in.
The 5 racks of sticks have been in for about 2 1/2 hrs and the temp differences I am seeing between just below the bottom rack and just above the top rack is around 13*. When the PID ramps up to the next set point the difference increase to about 18* and then settles back into a 12 - 13* once it gets to the set point. This happens fairly quickly.
As far as the fan mod goes, we may not all have the same expectations or end goals. My desire was to be able to put whatever into the smoker, set the PID and walk away until the stuff was done, without having to rotate the racks. I don't think this fan is going to produce that. But I will have a better understanding of what it will or won't do after my sticks are done later today. Right now they are in the smoke cycle.
My sticks are racked - not hanging and maybe as Sailor points out the results may be better if they are hung.
the biggest problem i see in this type of fan mod is that the fan is above the v tray. To a point it is good, however the bulk of the heat is still under the heat tray and of course the bottom will be hotter.
I still believe that my heater fan is still better over all for heat consistency through out the cabinet i have checked it the temps a while back .. once up to temp there was less then 5 degrees between top and bottom unless the heater was on them it climbed.
here is the link to my mod
http://forum.bradleysmoker.com/index.php?topic=17329.0
Now this is just my opinion but I think part of the problem is that the small fan just does not move enough air to overcome the racks, frog mats, food, ect. The temps look even when the cabinet is empty but changes with a load. That CFM rating has to be lower when the cabinet is loaded. I think it more has to do with fan blade size than location. The whole point is to circulate the heated air in the cabinet.
I would think the larger fan blades will yield better results.
Here's an update on my smoke - I am not going to get realistic results today because of the wind. :( It has been blowing all day and once in awhile a real big gust comes along for about a minute or 2. The outside temp is 9*C.
I was watching the therms and the temps were 10* apart and a really big blow came along and the temp on the top dropped by 10* in less than a minute and smoke was blowing out of where the SG connects to the box. I thought my Bradley therm was going to get blown off the top of the smoker. It took quite a while for the top temp to recover from that and I am thinking it is just too windy today.
Woe lot of good info since I left this morning. Thanks for all the input. Gonna wait to see if JZ has any luck with a bigger size. :)
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I put the Butt on last night at 10pm. Forgot all about the time change so basically it was 11pm :o At any rate I preheated to 225 and top and bottom were spot on. Loaded the 10 pound Butt and temps came down but both top and bottom were within 2 degrees of each other. I used the PID meat probe to stick in the meat so broke out the maverick to get the top temp readings. I rolled smoke for 4 hrs and changed the water and went to bed at 3am with both top and bottom reading 225. This morning I changed out the water again and Butt was at 150 and top and bottom at 225. It is now 12:30pm EST and I upped the smoker to 250. The Butt is at 171 and top and bottom temp is at 237 with 1 to 2 degree difference.
What does all this mean? Well, I think someone already said that the use of frog mats and having stix and jerky laying horizontal may be the problem. I think I tend to agree with this. With a empty cabinet the fan keeps temps with 2 degrees. When I am doing nuts or jerky I get a 20 to 25 degree difference. I put a Butt in and keep within 2 degrees.
Personally I think the small blade is doing what it is intended to do. We are moving air. It may not be enough for some but for what I want it to do it is just fine. I personally will not be making any adjustments or adding any blades or putting bigger motors on. I am very happy with what I gots. Just thought I would give my results.
Yeah I know.....no pics didn't happen ;D Will go out and shoot a couple of shots and post in another thread. Was to busy last night to get the prep shots.
Quote from: Sailor on March 11, 2012, 09:41:15 AM
I put the Butt on last night at 10pm. Forgot all about the time change so basically it was 11pm :o At any rate I preheated to 225 and top and bottom were spot on. Loaded the 10 pound Butt and temps came down but both top and bottom were within 2 degrees of each other. I used the PID meat probe to stick in the meat so broke out the maverick to get the top temp readings. I rolled smoke for 4 hrs and changed the water and went to bed at 3am with both top and bottom reading 225. This morning I changed out the water again and Butt was at 150 and top and bottom at 225. It is now 12:30pm EST and I upped the smoker to 250. The Butt is at 171 and top and bottom temp is at 237 with 1 to 2 degree difference.
What does all this mean? Well, I think someone already said that the use of frog mats and having stix and jerky laying horizontal may be the problem. I think I tend to agree with this. With a empty cabinet the fan keeps temps with 2 degrees. When I am doing nuts or jerky I get a 20 to 25 degree difference. I put a Butt in and keep within 2 degrees.
Personally I think the small blade is doing what it is intended to do. We are moving air. It may not be enough for some but for what I want it to do it is just fine. I personally will not be making any adjustments or adding any blades or putting bigger motors on. I am very happy with what I gots. Just thought I would give my results.
Yeah I know.....no pics didn't happen ;D Will go out and shoot a couple of shots and post in another thread. Was to busy last night to get the prep shots.
Good info, thanks. :) I BELIEVE YOU, even with no pics:)
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I suspect the reason some people have uneven temperatures in their smokers is because they put too much meat or sausage in their smoker, either sausages, jerky, or fish on racks, or hanging sausages. There needs to be enough room between the meat products for the smoke to circulate. You could put several temperature probes in your smoker and experiment with different densities of meat, possibly using pieces of 1"x2" wood or pieces of heavy aluminum foil to substitute for meat products. You could start by measuring the temperature with empty racks, then measure with lightly loaded racks, medium loaded racks, and heavily loaded racks. That experiment might give you a feel for how much room you need to leave between the meat for air circulation.
I know that some people have reported uneven temperatures with empty racks. I suspect that they need a bigger fan, or a second fan at a different location in the smoker. The temperature certainly isn't going to get more even when you add meat to the racks.
Thread resurrection!
Question for those of you with the fan mod...
The moving air hasn't caused any ash to fly around in the smoker? Like the idea, but don't want to get ash on the meat.
Also - have any of you tried the cylindrical fan blades that don't push air forward or back, but 360 degrees out perpendicularly to the fan shaft? That might do the trick not sure if it would even need a shroud/shield, and would not pull heat to the back (eliminating need for exterior cooling fan...)
Any comments/suggestions appreciated.
- Dan
Rider, don't have a fan mod, but here are some thoughts on your questions.
In a Bradley, ash wouldn't be a problem. Pucks do not burn to ash. They burn to the point of carbonization. Then pucks are discharged from the puck burner into a water filled puck bowl while they are still intact in a puck form.
I think the use of fan shrouds is as much a function of where the fan mods are usually located (below the bottom food rack) as they are a function of the style of fan used. Without a shroud to control and direct air flow, I'd think that any fan would have a tendency to stir a small pocket of air, rather than circulate air thoughout the smoker cabinet. I remember seeing pictures of a fan mod that used a squirrel cage fan, and the person who did the mod built a shroud to control the air flow.
The cooling fans on some fan mods may be a bit of overkill. The back wall of the smoker is insulated, so any heat a fan motor is picking up from inside the smoker should be coming from the motor shaft, not through the wall of the smoker. As forum members engineer things like fan mods, they tend to err on the side of caution. Since heat is bad for electric motors, installing a cooling fan helps ensure that the fan motor won't overheat. Don't know if it needs a cooling fan. But, for a few bucks, it's cheap insurance that the mod won't have to be rebuilt due to a motor failure.
I hear you on the exterior cooling fan, just means I need a longer shaft to accommodate both blades.
I've done some testing with my maverick and the Auber dual probe PID and the heat in the back (and bottom, bit more in the back) is higher than the front. I think the fan location of just below the bottom rack in the center of the back wall is the best place for evening out the heat.
Just bought the 900w element, now trying to find a suitable motor.
- Dan
Rider, this is what I did to mine and it works great. I pull the v tray as far forward as I can before closing the door, that way the heat goes right up to the fans to be distributed. I used 2 1/2" blades from grainger.
(http://i1281.photobucket.com/albums/a508/myrsdavedave01/P1080510-Version2_zpsa3b52b9f.jpg) (http://s1281.photobucket.com/user/myrsdavedave01/media/P1080510-Version2_zpsa3b52b9f.jpg.html)
Good luck, Dave
Dave - that looks like an excellent set up. Any chance you could post up the fan motor and blade parts you used? Did you also use the original heat shroud over the 900w element? Maybe also provide a pic of the motors mounted to the back?
Any help appreciated - going to pull the back off and try to install the 900W element over the weekend, and will get more familiar with the parts to plan for the fan mod(s).
_ Dan
Rider,
The fan motors I used are Dayton 4M077D. The blades are aluminum 2 1/2" clockwise. I got everything from Grainger. Total cost was about $100.00
The heat shield is used now on the edge of the bottom tray just to keep droppings off the fan blades and direct them to the drip pan.
I mounted theaters into 2 steel electrical boxes and after centering the motor shaft in the hole just drilled though the box in all for corners through the smoker. You can see the 4 bolts around each motor in the photo. The 900 watt heater is just mounted to 1/8 aluminum and I used the existing wires.
Let me know if you have any other questions,
Dave
Dave, has you looked at your heat distribution with your dual fan mod? I'm still chewing on Rider's fan shroud question and trying to figure out if fan shrouds are necessary, a good idea, or overkill.
tskeeter,
on the rack above the fans I use the old heat guard to keep drippings from hitting the fan. No fan shroud. I leave the drip pan all the way forward so that the heat can come up the back wall behind the fans, it seems to be the fastest way to distribute it. I have smoked quite a few racks of ribs and fish and have never had to rotate racks, everything is done at the same time.
Dave
Thanks Dave! Your's is the first dual fan set up I've seen. I've been kind of looking for something to even out the temp distribution in my six rack and it looks like your solution would do the trick with minimal fabrication effort.
Did you do something to beef up the the back of your smoker as you mounted the fan motors and their boxes? Or did you find the back wall of the smoker, combined with the back panel were heavy enough to provide adequate support for the weight you hung on them?
tskeeter,
I didn't do anything with the back of the smoker but if I did it again I would beef up the back a little or cut bushings to fit over the bolts between the inner and outer walls of the smoker. It would make it easier to tighten the motor down without throwing the shaft out of alignment. Either way it's not a hard mod to do.
Dave
Thanks, Dave. Bushings is an option I hadn't thought of.