Soft fire brick weight, K23

JTknives

JTknives

Blade Heat Treating www.jarodtodd.com
Knifemaker / Craftsman / Service Provider
Joined
Jun 11, 2006
Messages
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I'm in the process of rounding up all the things I need for a heat treat oven build and I have been looking for firebricks. I want the good K23 bricks so I have been calling around. There is a good deal on eBay but shipping is a killer and costing almost as much as the bricks. so I called www.sheffield-pottery.com as thy seam to be a big brick dealer. I told them I needed 40 bricks and wondered what the shipping cost would be. She said it would be over $200 for shipping, in my shock I asked why and she said because 40 bricks weighs over 200Lbs. I said no I need the soft K23 fire bricks not the hard. She says that is the soft bricks, thy weigh 5lbs each. I told her that seams hard to believe and she says that's what thy are and the hard are 8lbs each. So my question is this, are these really 5lbs for a 9"x4.5"x3" stright. I was trying to find densitys listed for these bricks but no luck. It seams like if my memory is correct that in the past when using these bricks thy could not be more then a few pounds each. If there soft bricks are that much heavier then real K23 then I'm thinking I should steer clear of them. Thanks guys, I will start a post later about the oven build, it's going to be rather sweet.
 
It depend on size (dimensions) of the bricks. It have about 480kg/m3. Standard dimension 230x114x74 mm should have weight cca 0,9kg (cca 2lbs). Maybe the bricks she offered to You are fire clay bricks ?
 
Yeah I don't know, when she said 5lbs I said no soft fire bricks for heat treat ovens and kilns. And she said yeah 5lbs each for the 9"x4.5"x3"
 
I get this often with other light weight supplies. What she is quoting is the "Shipping Weight". It really isn't the actual weight. Soft bricks are often individually packaged to keep them from damage.

I will occasionally order ten of something that weighs only an ounce or two and the shipping is calculated as ten pounds.

Check out High Temp Tools and see what they will charge. Also send a PM to Charles at Atlas. He buys by the truck load now.
 
JT, I'm sure you have chased this option down, but see if there are any pottery/clay supply places in your area. I found a hole in the wall pottery supply store that sold me K23 bricks individually.
 
There are hard and soft firebrkcks
Don't call them soft firebricks



Call them Insulating Fire Bricks


I weighed one.
910 grams per brick
That's 2 pounds per brick..



Try Morgan Thermal Ceramics webpage and find a different dealer.
 
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I get mine from Pennsylvania, BNZ Materials. I'm super happy with the quality compared to Morgan. However, I've ordered a couple pallets from Washington. Are you close to seattle? They've got bricks in stock, I believe, $4.50 each for K25 3". Might be worth the trip over.

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I'm in rice which is a few hrs north of Spokane which is like 4hrs from Seattle. I found a place in Spokane that had the bricks, thy where more then happy to sell them to me at a whopping $10 each lol. The eBay guy has the real K23 for like $62 a case shipped (10 bricks in a case).
 
Morgan Thermal Ceramics insulating fire bricks JM23/K23 are the best bar none, they weight around 900 grams (2lbs) the texture is chalky and the colour is not white, its more like cream.


Pablo
 
Also, go with K26 instead of K23, the manufacturing process is slightly different and the brick is much higher quality. They weigh a few ounces more, but it's definitely worth it.
 
JTknives said:
I'm in rice which is a few hrs north of Spokane which is like 4hrs from Seattle. I found a place in Spokane that had the bricks, thy where more then happy to sell them to me at a whopping $10 each lol. The eBay guy has the real K23 for like $62 a case shipped (10 bricks in a case).
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I have dealt with this situation in the past by talking to the store owner. I show them the printout of the online source and tell them that I would rather shop local, but can't pay them nearly twice the price. If they are willing to meet the price, I will buy from them. Some just say, "No", but others have been willing to get the sale and met the competition price.
 
I have to disagree here.

For a forge (which is after all what Atlas do), I'd completely agree that the JM23/K23 are not the best choice. I have tried other IFBs which are much more resilient and which have a significantly higher melting temperature.

However, for an electric HT oven, which will never see more than 2300 degF, the better insulation afforded by the K23/JM23 IFBs makes them the better choice. In addition, they are easier to work by hand than the denser IFBs I have used. The difference is enough to be significant in terms of time taken and cost of tools when building a one-off HT oven. I built my first with "other" IFBs and my second with JM23s. With one exception, every one I've built since (I think I'm up to 7 now) has used the JM23s, despite them costing nearly twice as much here, because IME they are so much better for HT ovens.

The exception was a sword-length oven built quick, cheap and dirty. For that, I used Ceramic Fiber board for the roof, backed up with Calcium Silicate board, which meant I could build it with a 9" wide chamber without having a problem spanning the gap. As a result, I only needed to cut 2 bricks to fit. I was not greatly concerned about the lower insulation value because it was only ever going to be used for Carbon steels, though I did test it to 1100 degC, 2012 degF. I had the cheap IFBs to hand because I'd bought in enough for a couple of forges.

I use a router to cut the element grooves and the cutter has no problem at all with any of the IFBs I've used so far. Filing the grooves into the first one was enough. Sawing the JM23s is easy with a cheap hardpoint woodsaw and the saw lasts pretty well, though it's no good for wood afterwards. The others wear away the teeth and take the set off the saw *very* quickly.

For a forge, I've tended to go with cheap no-name 23-grade IFBs. These have lasted pretty well for my occasional use. When I was playing with burners, I used a chunk of a JM23 to restrict the opening on a forge and it dribbled. Peak temperature measured was 1445 degC, 2633 degF.

 
Thanks guys for all your help. Just order the 4 cases of k23, was looking at the k26 but thy are less efficent and more money. I will start an oven Build thread to continue this conversation.
 
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