BRADLEY SMOKER | "Taste the Great Outdoors"

Bradley Smokers => Smoke Generator with Adaptor (BTSG1) => Topic started by: KRAKMT on December 25, 2010, 12:17:27 PM

Title: New guy/ new project
Post by: KRAKMT on December 25, 2010, 12:17:27 PM
Merry Christmas!

So a couple weeks ago a buddy was headed to town to buy a smoker, his wife got a monster bull elk, old bull- think lots of sausage. I mentioned that my neighbor had offered me an old fridge/smoker because neighbor's wife wasn't a fan of smoked meat. Well after my buddy decided he didn't want to spend $ we started.
I think I have read every thread and have gleaned about as much as will fit in my brain. So then I ordered a generator.
Fridge inside is 17x19x31. It has 12 inches height space below which is where we plumbed in the smoke generator and the heat source. We welded in two baffles to make two separate chambers. We have a 1000 watt hot plate we plan to install in the back heat chamber but we might need more power.
We plan to install two 2" stacks between the heat chamber and the meat chamber. Same for between the smoke generator chamber and the meat chamber.   

Any suggestions/comments? We will revise the electronics after we see if the mechanics work.

(http://i1217.photobucket.com/albums/dd381/KRAKMT/IMG_3673.jpg)

Fridge/smoker came with a two inch square smokestack which doesn't seem like enough but we may just add a exhausting fan to remove the smoke and move the heat up.
   
Title: Re: New guy/ new project
Post by: DTAggie on December 25, 2010, 12:53:41 PM
Welcome KRAKMT.  I am no help but somebody will be along soon that is.  Board is a little slow today as well enjoy Christmas.
Title: Re: New guy/ new project
Post by: beefmann on December 25, 2010, 02:25:25 PM
here is a few ideas as well. first is a 900 watt finned heater ( and yes they make larger )

http://forum.bradleysmoker.com/index.php?topic=17329.0

and a timer / pid

http://forum.bradleysmoker.com/index.php?topic=17304.0

the timer switches between the smoking and the cooking, the pid is a  digital temperature control , if you are going to be running a 1000 watt or  more, you  do need a temperature controller  of some kind to regulate the  heat not  just regulate the  power to the  heater.

on that size of unit i would consider a fan or blower to move the air over the  heater and  back into the box, if possible mount the heating  element  near the top. the blower behind it and force the  air down along the back and into the bottom below your bottom rack and above your grease catch tray.

good luck and looks like a good project
Title: Re: New guy/ new project
Post by: BuyLowSellHigh on December 25, 2010, 02:33:23 PM
That looks like a very cool project!  Look forward to seeing how this goes.

A few of questions:

1.  What temperatures do you expect to run in the meat section of the smoker?

2.  How do you plan to control that temperature ?

3.  How does the smoke get into the meat section form the SG chamber ?
Title: Re: New guy/ new project
Post by: KRAKMT on December 25, 2010, 03:12:31 PM
Quote from: BuyLowSellHigh on December 25, 2010, 02:33:23 PM
That looks like a very cool project!  Look forward to seeing how this goes.

A few of questions:

1.  What temperatures do you expect to run in the meat section of the smoker?

2.  How do you plan to control that temperature ?

3.  How does the smoke get into the meat section form the SG chamber ?

We stuck the hot plate inside with a couple cinder blocks from outside(below zero) and were able to get to 165 within 7 minutes. I will be happy if it will hold 200 on the highend.
Ifn the mechanics work I will tackle the Pid. The hotplate has a control knob that we will stick out the back for early testing.
On the line on the inside(in the first picture) will be a row of 2 inch holes- 2 in the smoke chamber and 2 in the heat chamber. We have a diffuser/ drip cover to go over the holes and room for drip trays on the insides. We hope the two 2" holes will be enough but we can go bigger if need be.
I came to the forum before I drilled to double check to see if I was missing something.
Still need to put stoverope around the door, caulk a few gaps and figure out some racks but forging ahead. 


(http://i1217.photobucket.com/albums/dd381/KRAKMT/IMG_3671.jpg)
Title: Re: New guy/ new project
Post by: BuyLowSellHigh on December 25, 2010, 06:12:46 PM
Is the interior of the planned meat compartment metal or plastic ?  I can't tell from the pics.
Title: Re: New guy/ new project
Post by: KRAKMT on December 25, 2010, 07:29:18 PM
Its all steel- oldstyle steel.Probably from the 40s? Whole fridge is metal with 2inches of insulation all around it.
I had to dremel the hole for the generator because the hf hole bit wouldn't touch it.
Got the racks rebuilt and need to make a few adjustments and install sausage hangers somehow.
Title: Re: New guy/ new project
Post by: BuyLowSellHigh on December 25, 2010, 10:38:47 PM
Cool! 

Sounds more like a tank than a refrigerator.
Title: Re: New guy/ new project
Post by: KRAKMT on December 26, 2010, 07:08:30 AM

A couple questions and possible design option.
1. When smoking we need to exhaust the smoke. But what is the highend temp needed just for smoking?

2. After 2 hours of smoke there is no need to exhaust, right?
So the recirulation of air across the heating element should come from the inside of the meat chamber rather than from the outside?
I am thinking of putting a stand of pipe in the corner from high in the meat chamber all the way to the bottom into the heat chamber for my circulation fan. 
Thoughts?
Title: Re: New guy/ new project
Post by: KRAKMT on December 26, 2010, 07:45:23 AM
I am thinking about adding a fan like this

http://cgi.ebay.com/RUSSO-STOVE-CONVECTION-BLOWER-FAN-/160361158538?pt=LH_DefaultDomain_0&hash=item255645178a

that will vent smoke either outside or recirc air back down to the firebox.
(not that fan but to function like it and use an electronic air control to direct the air)
Title: Re: New guy/ new project
Post by: BuyLowSellHigh on December 26, 2010, 07:50:09 AM
The answers to your questions depends on what you plan to smoke and what you want to achieve.  Personally, I would lean towards a simple circulation fan inside the meat compartment to keep the air well circulated (as in a convention oven), but always with an open vent to the outside.  There will almost always be moisture that should be vented.  That is the way convection ovens are built.
Title: Re: New guy/ new project
Post by: Sailor on December 26, 2010, 07:54:06 AM
Quote from: KRAKMT on December 26, 2010, 07:08:30 AM

A couple questions and possible design option.
1. When smoking we need to exhaust the smoke. But what is the highend temp needed just for smoking?

2. After 2 hours of smoke there is no need to exhaust, right?
So the recirulation of air across the heating element should come from the inside of the meat chamber rather than from the outside?
I am thinking of putting a stand of pipe in the corner from high in the meat chamber all the way to the bottom into the heat chamber for my circulation fan. 
Thoughts?


1. If you are doing Butt or Brisket I would say 200 to 225 degrees. 

2. I think you need air exchange.  The meat will give off moisture and you have to exhaust it.  If you seal it up you will not release the moisture and the heat in the smoker will go down because the moisture is sapping all of the heat.  Sounds weird I know but a closed off vent will prevent the smoker from building heat.

I have been thinking about your project and how to make the smoke chamber and heat chamber work the best with the meat chamber.  Thing you have to remember is that heat rises and cold drops.  If you put a stand pipe at the top you are pulling hot air back into your heat chamber and not heating the colder air.   I guess if you have a fan that is changing the air you would be OK with that set up.  Pikeman (Kirby) built a smoker out of a RR switching cabinet and I bet he could give you some pointers.
Title: Re: New guy/ new project
Post by: Sailor on December 26, 2010, 08:06:07 AM
Here is the thread on how Kirby did his RR Switch cabinet.  You might be able to get some ideas from looking his photos.  http://forum.bradleysmoker.com/index.php?topic=18181.msg220803#msg220803
Title: Re: New guy/ new project
Post by: KRAKMT on December 26, 2010, 10:04:27 AM
Good call. I made a air vent cover for fresh air to get into the heat box and still building racks.
Do you all think the convection fan will circulate enough? and where to install, in the meat area and hope it draws the heat up from the hot box or in the hot box to blow up into the meat area? In the hotbox is much easier, single wall and plenty of room.
Title: Re: New guy/ new project
Post by: Sailor on December 26, 2010, 10:40:24 AM
KRAKMT,  Been thinking about your set up and by no means am I a certified engineer (I am certifiable)  ;D.  My thoughts are that with the smoke generator you are bringing in fresh air because of the design of the SG so you are getting an air exchange into the meat changer from the smoke chamber as it pushes smoke out the top from the smoke stack.  So with that I am thinking that you are ejecting the moisture from the meat chamber.  I don't think you will want to add a lot more fresh air in than needed.  What would happen if you cut a slot or hole from the heat chamber to the smoke chamber and then run your circulating fan drawing meat chamber air forcing it back into the heat chamber which will force it into the smoke chamber and back into the meat chamber? 

If you don't have a hole from the meat chamber into your heat chamber you will not run the risk of having grease drip into your heat element.  This is a good thing.  If you turn off your SG after the smoke you will still get an even flow of air going from the smoke chamber to the meat chamber back to the heat chamber and into the smoke chamber.  Seems to me that circulating the heat and air this way would give you what you are looking for.  The less "holes" that you have in the meat chamber the better.  This way you only have to have one hole in the bottom over the smoke chamber and if you get any grease drippings it goes into your water pan. 

You could cut a hole on the back of the meat chamber down low and pipe it to the heat chamber and have your fan mounted outside the box.  It pulls cooler air "from the bottom" and forces it into the heat chamber and then into the smoke chamber.

Not sure if you get what I am trying to explain.  ;D
Title: Re: New guy/ new project
Post by: BuyLowSellHigh on December 26, 2010, 12:15:02 PM
For heat and smoke transfer from the heat chamber to the smoke chamber you should be able to rely on the chimney or stack effect.  You should have an inlet into the heat/smoke chamber, an opening between the two chambers and an outlet at the top of the upper chamber.  The inlet and outlet can be about the same size in area, and you can easily damper both for adjustability.  The transfer opening between the two chambers should be at least as large as the inlet opening so that it is non-restrictive for flow from hot to cold.

For forced convection within the meat chamber, a capacity of 10X the volume of the closed chamber should be plenty - you're not looking for a hurricane, just a steady, gentle stirring of the air.  In it's simplest form, just a circulating fan inside, will probably require that the motor be outside.  A more complex but probably more efficient design would be augment what would be natural convection by taking hot air from the top of the chamber, running through an external duct, then injecting it back into the bottom of the chamber.  A "squirrel cage" fan similar to pikeman's RR-switch cabinet would work great, but again don't overdo the  flow capacity.  If I did the calc right you have ~ 5.8 cu ft of volume, so something on the order of 40-60 cfm should be plenty.

Just a thought ... one design for the heat & smoke transfer that you might want to consider would be something similar to that used in the larger smokehouse from SausageMaker -- this one (http://www.sausagemaker.com/45200electricsmokehouse100lbstainlesssteelinsidealuminumoutside.aspx).  It is similar but larger to yours in that it has separate heating and smoking chambers.  In horizontal wall between the two there is a central hole that in the meat chamber becomes a stack with a deflector shield over the opening.  I don't think you need to extend the cap as high as they show, but the stack and cap allows the floor of the meat chamber to function as a grease catch.
Title: Re: New guy/ new project
Post by: KRAKMT on December 26, 2010, 04:14:14 PM
I really appreciate everyone's suggestions.
I had planned to use two chambers so I could separate the smoke process from the heating process. From reading many of the threads it seemed like the most efficient. And I had plenty of room under the fridge. I will post some more photos to show the progress and maybe a dry run. I can always add a fan or two after we see what our temp spectrum is. I had thought of the recirc plumbing from the top to the heatbox and was debating outside or inside but have to see if it is needed or if I am just over engineering.
We have a stainless defuser to go over the chimneys that lead up between the two lower boxes and with two cookie sheets to catch the drippings nothing should go down. We will stick our chimneys up a little to create a lip.
Title: Re: New guy/ new project
Post by: KRAKMT on December 26, 2010, 05:05:27 PM
UMMM,
Suggestions? The new 2" Milwaukee bi-metal hole saw manage to get through the paint after 4 minutes. Anyone know if they make a step bit in 2". Tells ya how heavy the metal inside is.
K
Title: Re: New guy/ new project
Post by: KRAKMT on December 27, 2010, 09:07:05 AM
Here is the latest photo
(http://i1217.photobucket.com/albums/dd381/KRAKMT/IMG_3680.jpg)
Title: Re: New guy/ new project
Post by: BuyLowSellHigh on December 27, 2010, 09:34:47 AM
Looking really cool!

I'm wondering if a metal blade on a jigsaw (hacksaw type edge) might be better for cutting through the metal liner ?  Drill hole, insert blade, cut away ?
Title: Re: New guy/ new project
Post by: NePaSmoKer on December 27, 2010, 05:26:57 PM
Porcelain coated metal. It chews up hole saws. a plasma cutter works good
Title: Re: New guy/ new project
Post by: Habanero Smoker on December 28, 2010, 02:18:14 AM
I've never used one on porcelain, but a Multi Tool Saw a.k.a. Sonic Saw, may work. If you have a tool rental shop you may be able to rent one for the day. You are probably won't have to cut through more then a 1/4", and will have to cut through both sides.

Or be on the safe side and rent a plasma cutter. That will make quick work of it.
Title: Re: New guy/ new project
Post by: KRAKMT on January 01, 2011, 08:52:40 AM
After the fiance recovers I will get some pictures posted. The welding shop couldn't plasma cut the holes because of the porceline liner and the paper backed insulation so they were able to grind off where the holes went and hole sawed in the tubes- stainless 2 inch tubes welded in.
Working on calking- I have some high temp silicon is that recommended?
Title: Re: New guy/ new project
Post by: Mr Walleye on January 01, 2011, 07:26:37 PM
I've used high temp silicone in the smokers I'm built and had no problem with it. It holds up well.

Mike
Title: Re: New guy/ new project
Post by: KRAKMT on January 01, 2011, 09:18:32 PM
Thanks Mr. Walleye. We will season it tomorrow.


(http://i1217.photobucket.com/albums/dd381/KRAKMT/1293934730.jpg)
Title: Re: New guy/ new project
Post by: KRAKMT on January 03, 2011, 08:50:20 AM
Quote from: BuyLowSellHigh on December 25, 2010, 02:33:23 PM
That looks like a very cool project!  Look forward to seeing how this goes.

A few of questions:

1.  What temperatures do you expect to run in the meat section of the smoker?

2.  How do you plan to control that temperature ?

3.  How does the smoke get into the meat section form the SG chamber ?

Test run went well, smoke flows out of SG and up the first hole.  I tied to get a pic of the smoke but not good enough photographer. Cool to watch as it streams up even without the front smoke chamber door on. I did get some reflux back out the SG mounting bracket when I open the main meat door and lost draft. Is that OK? I saw a horror post here of a burnt SG. It only lasts until draft restarts. Suppose I could open the bottom door anytime I open the meat area door.
The hot plate got the temp to 180 after along time. I guess I am now going to tackle the heating and PID. Time to reread all the posts about PIDS. I will go shopping for a fin element or two.

I did have a little acidic smell during the run- not sure if it was an overburnt puck or if I am getting a carcinogen off something. Any experts on toxins?
Title: Re: New guy/ new project
Post by: Mr Walleye on January 03, 2011, 09:34:33 AM
KRAKMT

On my large smoker, when I open the door, then close it, I do get some smoke backing up and out the generator. This resolves itself moments later when the draft corrects itself. I've never had any problems with my generator. I think the amount of smoke that gets in the generator in this situation is very limited. What you what to watch is that your top vent is open enough to allow the draft to develop as soon as possible after the door is closed.

I would suspect the acidic smell you got was off the high temp silicone. I know from my experience the high temp silicone gives of an acidic smell until it's fully curred. On my smokers I have ran smoke through them for a few hours at around 200 degrees to cure them. It does go away once it's curred fully.

Mike
Title: Re: New guy/ new project
Post by: KRAKMT on January 03, 2011, 10:47:38 AM
Walleye you are the barrier of good news. ;D The smell seemed like silicon and I had hoped that was what it was but the girl folks smelled it and.... I was also a little worried about the smoke venting since the stack is only 2inch but it recovers in under a minute. Just didn't want to burn the SG up.
Next, suggestions on PID and watts? I looked at your wiring diagram and calculations for the large one you did- seems like two 600 watt fins should be enough? I would think at 5.8 cu ft 30 or 40 pounds of meat would be max?   
would prefer 120VAC.
 
Title: Re: New guy/ new project
Post by: Mr Walleye on January 03, 2011, 12:06:06 PM
My first heating setup was two - 1100 watt finned strip heaters. These were 110v but had to be ran with a seperate power supply for each one. Although a single PID can control 2 seperate SSRs. Finned strip heaters are designed to have an air flo going over them. Without the air flow they will burn out prematurely. If you intruduce a fan in your design you will have to be carefull to not preasurize the lower "smoke" cabinet as this will cause smoke to backup out the generator.

It's hard to say on the size of element. I tend to go larger then I think and let the PID do it's job. Although keeping it running on 110v will limit the size. If you have a 1000 watt hot plate I would plug it in and throw it inside and see how it responds to 1000 watts of heat. It might give you a starting point.

Are you planing on having the element in the lower chamber as well?

If you use finned strip heaters and install a blower, where will your intake for the blower draw it's air from?


Mike
Title: Re: New guy/ new project
Post by: KRAKMT on January 04, 2011, 08:04:18 AM
I stuck the hot plate directly inside the smoker and the plate got it to 225 rather quickly. At 225f I opened the door for 1 minute- the heat dropped to 199 but raised back to 225 after 3 minutes.
so looks like I either need more power or a fan if I plan to use the lower heat chamber. I guess I could just put a couple bradley elements under my shield?
K
Title: Re: New guy/ new project
Post by: KRAKMT on January 13, 2011, 11:10:25 AM
I emailed the smoker project to an older cousin and brother and found out my cousin used to design electronics for case/ih. He is way into designing the electronics. I am wondering on the ball park smoking steps, the fish recipe I am trying calls for 130 preheat then smoke for xhours then finish at 175. I can reach that with convection but working on adding a fan over http://www.sausagemaker.com/49100electricheatingelementfor100lbsmoker.aspx to reach the higher ends.
My question is whether one ever needs to add smoke at say above 160 degrees? Taking Walleye's concern to heart about back drafting the smoke generator when using a fan. My exhaust port of only 2inches could easily cause that. But if smoke and heat can somewhat be separate function then shouldn't be a prob.
 
Title: Re: New guy/ new project
Post by: Mr Walleye on January 13, 2011, 05:54:21 PM
Krakmt

I guess weather you apply smoke above 160 depends on what you plan on smoking. Certainly if you are mainly doing sausage, jerky, fish, etc, then you may not be doing much smoking over 160. I use mine for many things such as butts, brisket, turkey, chicken, etc, which all are smoked above 160 so it really comes down to what you plan on using the smoker for the majority of the time.

Mike
Title: Re: New guy/ new project
Post by: KRAKMT on December 24, 2011, 08:16:01 AM

MERRY XMAS 2011

It has been a year and I have been working on the smoker between other projects-
So for a progress update-

Here is the schematic I used for the pid
http://i1217.photobucket.com/albums/dd381/KRAKMT/smoker.jpg
The controller will handle either 220v or or currently a 110v hotplate. depending I might add some btu if necessary.
It also has a fan controller that too can be added if necessary.
I will upload a few pictures but it still needs wheels, new handle and paint

So progress, it is doing its magic on a 22 pound turkey right now.
Title: Re: New guy/ new project
Post by: KRAKMT on December 24, 2011, 09:17:18 AM
- just bumped the turkey to program 17 on the pid. at 276 and climbing rapidly to 300.
(http://i1217.photobucket.com/albums/dd381/KRAKMT/IMG_2562.jpg)
Title: Re: New guy/ new project
Post by: CowtownSmoker on April 30, 2013, 06:35:43 PM
Personally I would not make a smoker w/ a plastic interior even at 225F.
Title: Re: New guy/ new project
Post by: KyNola on April 30, 2013, 07:13:21 PM
That's good because this 3 year old project didn't have plastic interior either. :o