Retaining heat .....

[outdoorsfellar]

Hello all ! It's been a lil while since I've looked around here due to being away for the last week & then some due to deer camp .... no, there wasn't any hunting involved, just a bunch of guys getting away from work & our wives. ANYWAY, while at camp, an idea came to mind & I wanted to ask here if anyone has ever done this. To begin with, we all know about using bricks to retain heat. What I come across at camp each year is one of my buddies uses a fire brick to heat his camper at night. This is a special brick just a bit bigger in size than a regular brick that is heated per a gas stove inside for a while, then the stove is turned off & the brick stays heated. Maybe this has been already discussed here, but since I keep seeing references to using a brick, I'm not so sure. I certainly think this is a good way of keeping the IT up, & has anyone ever tried this method ?

[FLBentRider]

I usually keep a foil wrapped brick in my smoker.

I saw mentioned here that someone heated their bricks in the oven at 500F first. I have not tried that.

[ArnieM]

Firebrick is intended to be used at higher temps than regular building brick.  It's typically used to line fireplaces or commercial furnaces.  For BS temps, I doubt it has much if any advantage.  The key to holding the heat is mass.  Maybe a firebrick has more mass than a regular old brick - I dunno, I'm not an authority here.

I have preheated my bricks (I usually use 2, space permitting) to 450-500 while the BS is preheating.  The bricks do help to reduce the preheat time and then later on stabilize the temp.

Others have replaced the stock water bowl with a cast iron pan and water.  Again, we have more mass here.  But, the cast iron is supposed to stay oily.  They rust quite a bit when only cooking water.  But, then, they'd have to rust a HECK of a lot before disintegrating.

[ArnieM]

Oh yeah, last thing.  I've also thought of using rocks.  They seem to be pretty dense.  Here in southern New England, I can barely dig a hole.  I have stone walls on all four sides of my property and one in the middle.  So, I figured I'd try a couple of 'bare' rocks.  I could put them back on the stone wall after they'd cooled down.  The raccoons, 'possums and skunks would probably lick them clean, ready for the next smoke.   :D  I'm doing a pork loin tomorrow and I think I'll give that a try.

[KevinG]

It hasn't happened to me, but I heard some rumors that rocks will explode due to the moisture content. The moisture boils and expands and blows the rock apart. I don't suspect cooking at low temps would be too much of a problem though.

[BigJohnT]

It's all about density. Bricks are 1922 kg/m3 and Fire Bricks are 2403 which is a slight improvement. Now if you chunk in a brick sized chunk of steel it is 7850 kg/m3 quite a bit of difference there. So my brick sized chunk of steel will have almost 8 times the density of a brick. Once heated it will have almost 8 times the energy potential as a brick. Even with that if you load 25 lbs of meat in the Bradley don't expect the temp to stay up until the heat energy has transferred from the 25 lbs of steel to the 25 lbs of meat.

John

[FLBentRider]

I don't want to see the shipping charges on a "JT Brick"

LOL

[outdoorsfellar]

Man o man, you guys REALLY get in to this & have great knowledge ! I appreciate that. So , the way it sounds, it looks as if a regular brick is a good way to go. At least I'm not going to concern myself with trying to remember to buy a different type of brick when what I have nearby will do the trick !

[BigJohnT]

I don't want to see the shipping charges on a "JT Brick"

LOL

Ya go to a local scrap yard and pick your own brick and wrap it with tin foil... that is if you don't want it engraved so it burns you initials in your hand when you pick it up  ;D

JT

[squirtthecat]

I use a square Lodge cast iron skillet w/ the handle lopped off...   It is just the right size to fit a 8.3x8.3" foil pan from WallyMart (you can get a 3 pack of pans for about $1.85 - they last 2 or 3 smokes each before they start to leak) inside of it to hold the water/spent pucks. 

I haven't had any major rust issues, but then I don't plan on using it for anything but this application!

[ArnieM]

I'm getting kinda worried about the rocks.  Yeah, it's been raining here quite a bit.  I know the rocks don't really absorb rain and the temp isn't too hot in the smoker.  But still ...

They've been building down the street a ways.  Maybe I could borrow a blast blanket to put over the OBS, just in case.  ;D ;D

I'd listen to JT.  He seems to know his thermo-dynamics pretty well.