INSULATING CASTABLE ( Firebrick ) REFRACTORY Start Price USD 43.06 Current Price USD 43.06 Time Left - Bid Count 0 Buy It Now Price - Reserve Price - Start Time Monday, August 18, 2008 End Time Monday, August 25, 2008 Location Benzonia, Michigan See more about 'INSULATING CASTABLE ( Firebrick ) REFRACTORY ' Description High Temperature Insulating Castable Refractory Each 50 lb Box makes 100 lbs of Castable Refractory after you add 50 lbs of your own all purpose Sand.100 lbs of Refractory is about 1.4 cubic Feet.1 cubic foot of finished refractory weighs about 73lbs. Build Your Own Kiln, Furnace, or anneling oven. Our High Temperature Insulating Castable Refractory is dry, cement based, High Alumina, insulating material which can be cast into a form to make a kiln or melting furnace for glass, clay objects, annealing ovens, metal casting, or any other use which requires resistance to high temperatures Pictured is a small (holds a #10 Crucible) furnace that we made by pouring the mix into Cardboard forms.    Forms can be made using the same techniques that are used to pour concrete. Wood, metal, cardboard, and other materials that will hold their shape while the cement based components of the refractory mix harden, can be used. Duct tape can be used to hold the forms together while the mix is curing. How to use your Castable Refractory: Add 50 lbs of Clean, Dry, All-Purpose Sand, add clean water, and mix well. It should be the consistency of cookie dough. Pour into the mold making sure that you have included the holes necessary for flame inlet, and exaust vents. While pouring, vibrate the mold to remove any air pockets or bubbles from the casting. Air pockets can be dangerous during the drying/fireing stage; Trapped air can explode as the furnace body is heated. Allow to cure for 24 hrs. Full strength will be acheived in 36 to 48 hours. Once it is cured, remove the mold material and allow it to dry (in the sun is good) for a couple of days or for a couple of hours at 200 degrees F.  Once it appears dry you can start firing it. Firing Procedure: Firing is critical. If you heat your new furnace too fast it will begin to steam. If it begins to steam it will form cracks. Castable refractory mix is sensitive to quick changes in temperature. Some cracks are usually ok, as long as your furnace remains substantially intact it should work just fine. The furnace shown is NOW over a year old and we fire it up about once a week. Over time it has developed some major cracks but it still works very well. Begin firing very slowly. Ideally, do not raise the temperature more than 100 degrees per hour. If it begins to steam turn of the flame and let it cool down until the steaming stops. There is alot of internal water to be removed. We, like most people, tend to be impatient and just blast away. For best results follow the above schedule closely. Once the steaming stops, turn the flame on again and slowly heat it up. Over time you will get to 2400 to 3200 degrees F and you can then let your furnace body slowly cool down. Additional Information: This particular furnace has 3" walls and the outside barely gets hot while the aluminum is molten inside the crucible, when fired the inside glows bright red and I can still touch the outside of the furnace... (Not a recommended procedure) This furnace took about 150 lbs of mix (3 batches) including the cover not shown. 12" tall inside x 8" inside diameter. You can add metal or carbon fibres, or other strengthing materials (up to 10% by weight) if you like. **** NOTE: CASTING METAL IS INHERENTLY DANGEROUS. YOU ARE RESPONSABLE FOR WHAT YOU DO WITH THIS PRODUCT. BY PURCHASING AND USING THIS MATERIAL YOU ARE AGREEING THAT YOU WILL NOT HOLD US LIABLE FOR ANYTHING THAT YOU DO IN CONNECTION WITH THIS PRODUCT. USE EXTREME CAUTION AROUND MOLTEN METALS AND HIGH TEMPERATURES. MAY CONTAIN FREE SILICA; USE A BREATHER MASK WHEN HANDLING THE DRY PRODUCT.********Contains Portland Cement wear gloves and avoid contact of the wet product with your skin *** This product is sold on the assumption that you are able to safeguard yourself and others in using this product. No liability or warranty is assumed by anyone associated with Frostic Inc. that this product is safe to use or that it is suitable to your specific application. Purchase a sample for your own evaluation before buying any large quantity of this product for use. see our other auctions or our ebay store for sample listings. You are purchasing 50 lbs of High Temperature Insulating Castable Refractory. Each Package makes 100 lbs of Mix after you add 50 lbs of your own Clean, Dry, All-Purpose Sand. Density of the finished product is about 73 lbs per Cubic Foot. 100 lbs of product is about 1.4 cubic feet. Please use the shipping calculator and compare the total cost with the cost of 100 lbs standard refractory shipped to your door. Place a Bid!