Where can I buy refractory CONCRETE?

[jbriggs]

Re: Where can I buy refractory CONCRETE?

Oh damn is should proof read more often.....

[azpizzanut]

Re: Where can I buy refractory CONCRETE?

Hi All,

For those of you that want to cast oven parts of refractory concrete I suggest you do your very best to calculate how much you need before starting a project. I made a cast vent from some bags of castable refractory left over from a job. I was certain the three bags would fill the form........it didn't, not quite. Fortunately, I was able to accommodate the shortage because the chimney base still fit the top opening.

The castable refractory set-up fairly fast but stayed tacky for several hours. A hammer drill with a suitable bolt fitted to the chuck made a good vibratory tool when pressed hard on the outside of the wooden form. Don't forget to do this or you may get lots of air bubble casts.

I lined the form with 2" wide box sealing tape. The finished surface of the vent was smooth as glass. I got lucky with that. From my limited, prior, experience with castable refractory I learned that it sticks to raw wood and makes form removal difficult. It isn't like Portland concrete. Maybe you will find my experiences helpful.

Cheers,

[david s]

Re: Where can I buy refractory CONCRETE?

You must use a release agent. I use 50% motor oil and 50% kerosene. This seems to work well, you don't want too much oil residue left on the cast surface, that's why I dilute it.

[olddough]

Re: Where can I buy refractory CONCRETE?

Anyone know of any sources for refractory cement and firebricks in the boston area? Planning on building a frankenwebber.
Thanks

[azpizzanut]

Re: Where can I buy refractory CONCRETE?

Hi Olddough,

If I recall correctly, the Frankenweber was first cast of regular Portland cement and perlite. This mixture makes for a suitable but temporary casting. You will see the videos of the Frankenweber where the edges are chipped, with deep cracks or broken areas.

If you want to buy bagged castable refractory then you need to decide which type since some are for insulating and some for their heat retaining ability. Also note, some refractory products are very heavy and the finished cast will surprise you with its weight. Maybe you can discuss your needs with a factory rep. If you use the Portland recipe then allow it to cure thoroughly before handling.

If you have a hard time finding refractory cement then maybe contact a boiler/furnace repair contractor for help in sourcing what you need.

Cheers,

[Jimney]

Re: Where can I buy refractory CONCRETE?

Menards in Michigan has 50 lb bags of refractory cement for $56. I don't know if they have any in your state, but it looks like you can order it on line. Right now there is a 6 dollar rebate per bag.