The Breakroom > The Water Cooler


<< < (3/3)

tom osselton:
Yeah that ITC 100 looked clear with gravely bits in the bottom but it works a charm with the blanket. Iíve always stayed away from cast furnaces due to having to dry the castings before pouring on the heat every blue moon but with the blanket just fire it up!

Well now I am earning a bit of extra "shop money" I can afford to splash out a bit, for now though the project I wanted the casting for is not a major concern so theres no need to rush into remaking it. When I first made it I did a lot of searching and did notice the plaster of paris but as it was going to be harder to come by went another suggestion which was portland cement. Live and learn I guess.

Tom do you melt iron?

Dwayne, my local hardware store carries plaster of Paris. It's used in walls. So very easy to find -- as easy as Portland cement. It comes (dry) in gallon plastic tubs, and larger quantities in bags.

But it is NOT the same thing as drywalll or joint compound, or spackle, both of which dry very slowly by evaporation. Those are completely different materials and unsuitable for a furnace, and also would never dry in the thickness needed.

Plaster of Paris, cures by chemical reaction with water, releasing heat. It cures very quickly and you have to pour very soon after mixing it. It is fairly inexpensive -- not a lot more than cement.

tom osselton:
I havenít cast iron yet I want to though aluminum and brass Iíve done. I would like to get a size 20 crucible (or at least bigger than my #6) I stayed out of the backyard this year to let the fox raise her litter.

Thanks Tom.  :beer: Well iron temps with an oil blast furnace are much, much harder on a furnace lining, so I was just wondering when you said the ITC 100HT coating works a charm with the blanket, whether that was with experience at iron temps and melting times.

Looking at what I've done here, I'm a little skeptical yet that this coating is going to work well on an iron furnace. It seems very fragile over the soft fiber insulation.

The coating Ironman uses in the videos looks to be a very different consistency going on -- fairly thick and syrup-like and doesn't appear to absorb into the blanket like this very thin water mixed stuff does. The Australian product paints over the surface, and appears to give a rigid coating.

Even two coats of the ITC 100HT doesn't give much thickness, It seems fragile/crumbly and there are small flaws and folds where the white of the blanket shows. Brushing over the flaws doesn't bridge gaps well.

Well I guess I won't be able to tell until it gets fired. Maybe it hardens up into  a more rigid structural shell. I want to wait for a first heat until a little warmer weather is predicted. As I understand it it also needs a lower temp initial cure, not to exceed 600F for 6 hours. We have -4F predicted for Thursday night, and won't get above freezing until next week.


[0] Message Index

[*] Previous page

Go to full version