Matrikote, plistix, or itc?

[Gijotoole]

I know these have a different purpose, but I'm trying to find a way to get my brick forge hotter. Everybody uses itc, but it'd pricey and hightemptools charges more to ship it to me than it costs. I have heard plistix isn't as good, either. I can't find metrikote anywhere on the forum. I'm using a zoeller mod sidearm-no guage so I'm not sure what psi I'm at but it's full open backed off 4 turns on a bayou 0-30. I did s bit with Tom McGinnis over a year ago, to make a couple hawks, and he uses a blown burner. Do I need forced air to reach the right temps? I'm just starting this craziness so I can't get HH6 to tie off on the full-up forge layout. That, and I'm probably not supposed to be doing this in my backyard.

Thanks for the help, all of you handsome, kind, burly, wickedly smart and talented prople.

[SoCal Dave]

An attached photo of your forge might help.  What temp is the right temp for you.  I believe you will get higher temps with forced air, but is it what you want/need.  With forced air you get a lot more O2 and scale.  The addition of a blower may not be your problem if you forge is not retaining the heat.  You can reach welding heat with a one burner forge if it is the right size, reflects the heat, and retains the heat and has the right mixture of fuel and air.  Good luck.  

[Frosty]

You can get more than welding heat from a sidearm burner as you can with one of my "T" burners. They were both born of a coffee table napkin sketch talk some years ago but that's an irrelevant story.

 

A gauge would be a real help, if you're cranking the regulator to 30psi you're NOT helping things. A 3/4" sidearm running at 9+psi should bring the bulk of a 350 cu/in forge chamber to med yellow and have a sweet spot under the burner that'll melt steel.

 

Are there ceramic studios or suppliers available? If so you should be able to buy kiln was, ITC-100 is a kiln wash but there are others. More than a good IR reflective kiln wash your forge needs some insulation. If you can buy a small quantity of kaolin clay (porcelain when fired) You can mix it with dampened sawdust and when it's tempered, that's allowed to rest in a sealed container till the moisture is equalized through the mix, a day or so, you can ram it into bricks. When dry you bisque fire them slowly and burn the sawdust out leaving voids. Then final vitrifying firing evacuates the voids and seals them into little vacuum chambers for decent insulation. Porcelain is a high cone 12 ceramic and being high alumina is resistant to caustics so flux ill have minimum effect.

 

You can do the same with fire clay and make light fire brick but it will be susceptible to flux damage.

 

Frosty The Lucky.

[Gijotoole]

My pic is my forge. I live in Germany and it's relatively impossible to find stuff on Google over here. The setup I have now is three and a half 4x9x1" hard fire bricks, to make the chamber, with a vermiculite ceiling. The entire thing is surrounded with ytong, an aerated concrete, to form an insulative case around the chamber. The bricks are heating up real fast, glowing for quite a while after the gas is shut off, but the ytong is baking and falling apart at a rapid pace. I have used this twice and I should probably replace my faceplate to the chamber. The vermiculite is baking right through and is falling apart like crazy. I have pretty much cooked the whole thing a few times.

The temp is about 40* here and I use scrap to warm the anvil before I start striking. I think I'm just going to give up on welding until I get back to the states. At least I can gnd some good stores there. Shipping costs are killing me. Any more suggestions are appreciated.

[Gijotoole]

Has anybody heard of Matrikote or used it? If Kaolin clay turns into ceramic after firing, can I use ceramic tiles to line the forge walls inside the chamber?

[VaughnT]

Hard firebricks are not a great insulator.  The aerated concrete surrounding it is even worse.

 

Having said that, coating the firebricks like you intend will make a great difference in how hot it gets.  Metrikote is good stuff according to Wayne Coe's website:    Metrikote IR reflective (similar to ITC 100 and Plistix).  My supplier builds large furnaces, kilns and forges and tells me that they like the Metrikote better than the Plistix.  The last time I re-coated my gas forge I used the Metrikote and it seems to work well and hold up well.  Not having done a side by side comparison I can not determine if one is better than the other.  $15.00 per pint plus shipping.

[WayneCoeArtistBlacksmith]

I have Plistix at $10.00 per pint and Metrikote for $15.00 per pint.  I have used both and ITC-100.  I have not done any side by side comparisons but I believe that the main difference is that Plistix costs $10.00 a pint, Metrikote $15.00 a pint and ITC-100 is $69.95 per pint.

 

My supplier is a builder of large kilns and furnaces.  They used to use Plistix and switched to Metrikote.  When I ask why they just say, "We like the Metrikote better."

They now have to special order the Plistix for me. 

[Gijotoole]

Mr Coe,
What would the price be for 1 pint of metrikote to apo, AE 09139?

[WayneCoeArtistBlacksmith]

It looks like a Small Flat Rate Box (which will hold up to 3 Pints of Metrikote) is $5.80.

 

Send me a PM for further information.

[timgunn1962]

Has anybody heard of Matrikote or used it? If Kaolin clay turns into ceramic after firing, can I use ceramic tiles to line the forge walls inside the chamber?

 

Ceramics are a whole class of materials. Rather like metals.

 

Most ceramic tiles are not up to handling the temperatures we need.

 

Unglazed porcelain floor tiles are a relatively new development, in part made possible by the development of the technology to fire big flat tiles to the sort of temperatures needed for porcelain.

 

I cut a porcelain floor tile to fit in my HT oven and it's much more resilient than the soft brick. It cracked, with a single crack about 16" long, after the third time up to 2200 degF, but is still in one piece.

 

I don't think it would be good for forge walls because I don't think it could handle the temperature gradients in a typical forge (a heat-treat oven is intended to give even heating, it is a large part of the design brief. Most forges can happily function with a relatively small hotspot) or the much higher rate at which the temperature rises on startup.

 

If I build a flat-bottomed all-fiber forge anytime soon for forging temperatures only (i.e. not welding), I'll try a removable porcelain tile floor.

[Gijotoole]

Mr Coe et al,
The ytong (aerated concrete) I have now, although falling apart rather expeditiously, is cheap and easy to get. If I replaced the interior of my forge with ceramic blanket and coated with metrikote or plistix while keeping the shell as-is with the ytong, would that serve the same purpose at a standard barrel-type forge? The concrete is very easy to cut and the local hardware shop has it in massive supply. Mr Coe's prices make the ceramic blanket and metrikote/plistix very attractive. I appreciate the help from all of you. I still have problems sleeping at night before a day with an open schedule (filled-in with heating metal).

This is great!

[WayneCoeArtistBlacksmith]

The Metrikote nor Plistix have any strength.  If you paint it over the ceramic blanket you will poke a hole in it every time you touch it with a piece of metal.  I suggest casting over the blanket about 1/2" thick then paint over that with the Metrikote or Plistix.

[Gijotoole]

So could I use ceramic blanket between the hard bricks and the concrete and coat the hard bricks with metrikote? Is that the same as using a castable refractory? If I went that route, would I still need to coat the blanket to avoid airborne (GERONIMO!!) fibers?

[Gijotoole]

I can find schamottemörtel, which is fireplace mortar, that has a 1400*C max temp and sold in 5 kilo bags. Can I just mix this with some sawdust for insulating bricks? I can build a brick form pretty easily but I don't know how to fire them. How about a fire pit with some charcoal? I could also just pour/ram it between the hard bricks and the concrete I have now. I'll use the search button a bit more to see what I can dig up.

[Gijotoole]

I looked-up bisque firing-recommended cone4-8 temps. That's over 2k*. I don't have a device or know how to regulate that high of a temp. I don't have a pyrometers nor do I have a thermal-regulator-solenoid-thingy. Crap. I actually caught my concrete on fire for a little bit today. I'm going to hold off for a bit until I get my pressure guage.

[Gijotoole]

Bump. I'm using some vermiculite board to shield the hot spot from the concrete, which has helped improve the life of my concrete on the sides, but would painting plistix on the inside of the chamber act the same as painting it on some castable? I can get fireplace mortar that's good to 3000, would that work in place of cast able also? I hit the search button again, thanks.