Guidance on refractory, crucible size and ceramic tidiness

Hello all!

I have a CastMaster GG-5000 that I picked up from a local Craig’s list ad. I am very new to the hobby and come to ask humbly for some guidance.

First lets get to the pictures so we can discuss properly!

Refractory:

I would like to add some refractory before I do my first burn. Satanite seems like the most recommended option as I have been reading through the forum. Do you all think going with a DIY slurry of Satanite is the best bet here?


I am concerned that the crucible that was shipped with the unit is too big. Especially considering that I would like to add refractory to the furnace. I have taken some measurements, but I remain unsure as to the numbering system of the crucibles. I think it is a #5 and I would probably do ok with a #4 or #3…???



Ceramic wool tidiness… Well as you can see from the back of the furnace, the wool overlaps itself near the hinge. Before I make a cut to form a butt joint, I wanted to get some opinions on whether or not I should. Also, when I shut the furnace lid it seems like the wool is busting out where the lid and body touch.

Should I try to compress the wool and tuck it into place a bit better?

Thank you in advance!

 

Satanite. Paint a thin layer, fire it red, cool down and repeat 2-3 times.

I would straighten on that kaowool before you coat it. Wear a mask when screwing with it. Welcome aboard.

 

https://www.ebay.com/itm/174865785492?hash=item28b6d02294:g:P9sAAOSwUbVhHqff
https://www.ebay.com/itm/184971991733?epid=1900191866&hash=item2b11309ab5:g:0K8AAOSwIThhA-2-
A couple of guys I know of use tools similar to the links above to lift and pour their small crucibles. I’m not suggesting that you buy them, just showing the idea. The tongs have 3 points of contact when lifting from above. The crucible can be lifted out, set on a flat surface, and then the tongs can be repositioned for a side grip for pouring. Or else use the other type of tool for pouring. Just make sure they are robust enough to handle the weight. You need enough room to get the tongs around the crucible without too much contact with the sides of the furnace bore.
If you go to https://www.lmine.com/graphite-crucibles-c-1_2_142/ you will find crucibles listed with their dimensions. I use the “budget” crucibles for aluminum and “salamander super” for higher temp like bronze and cast iron. The numbers and letters you see describing crucibles can be confusing so I’d go by specific dimensions for the time being.
Don’t worry to much about altering the manufacturers installation. They’re obviously not rocket scientists. If that wool is just stuffed in there I’d take it out, lay it on a bench and cut the ends of the wool at a bias to match. Cut ends at an angle to get maximum overlap. It cuts easily with a razor knife. Even if it’s glued in you can probably trim it insitu.

Pete

 

You need to get the wool as smooth as possible especially the lid and where it meets the body wool. That will be the seal for the lid. Chamfer the wool around the vent and the burner entry with scissors. I cut the wool at the burner enough to make a cone that acts as a flare. A couple coats of Satanite will add about 1/8" to the wool so cut it back to accommodate it.
Five pounds of Satanite will be plenty.
Did you see my video of application?
One thin layer at a time bringing each layer to red heat. No more than two layers on the unsupported part of the lid.
Where the lid and body meet you can paint multiple layers on to get a good seal. If you can get the hinge loose you can spin the lid to lap the joint and you will get a perfect seal.

 

From your pics, that crucible does look a little too big for that furnace but my advise is, leave it for now and deal with the Satanite coating first, that will stabilize the Kaowool and maybe compact it a little, at that point, you'll be better positioned to determine if a smaller crucible is warranted. And once you've settled on a crucible size, buy or make a set of more appropriate tongs, ones that do better than grip the crucible by a single point on its rim.

 

Thank you all very much for taking the time to read and provide feedback. I am now very comfortable with how I am going to get to my first burn.

1. Trim wool and tidy it up
2. Procure Satanite, apply, and cure - This video: @FishbonzWV ?
3. Order some decent tools for handling crucible
4. Check crucible fit and fire that darn thing... chomping at the bit to get to this part!
5. Order new crucible - one for copper

After I have done that a few times, I am going to procure the ingredients for sand casting... can't flippin wait.

 

That is a beauty furnace. Would love to see what it looked like after the excess wool was cut, that crucible did look a bit cramped to me.