Forge rebuild: castable refractory

[Urthman]

Hey folks.  My propane forge has served me well, but two years of hard use have beat up the interior (kaowool with satanite coating)

I'm getting ready to cast new solid interior walls (using Kast-O-lite 30).  I'll still use kaowool to surround the Kast-O-lite casting.

My initial plan is to cast the interior all in one piece- but I'm a bit worried about how prone to cracks a 1-piece design would be.

Have any of you cast a forge interior in one piece using Kast-O-lite?  How did it hold up?  Should I cast the interior in several pieces, and/or add some metal mesh to bind things together?

I'm very interested to hear from folks that have actually done this.  Thanks!

[John in Oly, WA]

My forge is a one piece Kast-o-lite 30 interior with kaowool outside of that, all inside an old propane tank. I've only fired it up about a dozen times so far (I'm a noob), but it's handled the temp cycles fine so far. Being a noob, I never thought about a one-piece design cracking (red face).

[WayneCoeArtistBlacksmith]

Check out the Build A Gas Forge attachment at www.WayneCoeArtistBlacksmith.com.  You will see that the way I like to build a gas forge will cure your problems.  It also be good to paint the interior with Plistix or Metrikote infrared reflective to increase the efficiency of your forge.  You should have no cracking, if you mix the Kast-0-Lite dry.  Cracking comes from the evaporation of the water and therefore shrinking. A dryer mix will also yield a stronger casting.

Let me know if I can help you.

Wayne

[Urthman]

Thanks for chiming in guys.

Wayne- Interesting design!  The split feature allowing you to raise the roof is particularly clever.

[Mikey98118]

Ive used a three piece design; cast cylindrical hot face wall, with high alumina round kiln shelves for front and back walls with separate pieces of insulation behind each face,