Metal Casting Zone

mctc wrote:
excitedly waiting for the results. They look good. Thicker then I had imagined.too thick ???? the book said 5/8 of an inch all round. these are just a bit over 5/8 but not 3/4.

OddDuck wrote:
Just a hint to help keep it from cracking, fire it with the opening down, in other words upside down. Put a piece of cardboard between it and the floor of your furnace to make sure it doesn't stick to it. I'm interested in the results as well, I have yet to make the follow-up to my cruciform rig, I was going to do it on my vacation but doing the rest of my roof sucked up all the time. Sometime in the near future, though. The nice thing about the Gingery method is that it does work, even if the mold is a bit cumbersome. Good luck with the firing! after the last "heat" from the oven i took one straight to the furnace.... loaded it with brass .... slowly got the fire going... then went for the melt.... it was just a small melt to try and i must say i was surprised just how smooth the pour was. just a stick of 5/8 brass to use in the lathe.

thanks guys. im calling it a success. flushed with just how well the crucible held up i went for a full melt but it was getting late and....... (9 pm at night) i poked at the brass thinking that it had bridged in the top and..... cracked the crucible. ...my fault... ah well i have seven more left to play with.

Sounds good XL, keep us posted.

a few more pics.
the mold assembled




the interior of the mold plus the firebrick samples in different stages.


my fault!!



you can see the unmelted fitting. this had a flange and i forgot the the pot was tapered as im used to the straight sides of my others. also the bar of brass from the first pour.

ive already ground the pot up but i kept this fragment . its from our first rammed pot and first fired pot... its very uniform in texture through out the profile.

I put a bunch of hockey puck ingots in a new clay crucible and cracked the whole side out. It was from the expansion as they heated up.

Well, that proves they do work. Just out of curiosity, do they ping when you tap the side or thunk? If they aren't fully fired they will be rather fragile and quite prone to cracking unexpectedly. The ones I have made I have tried to get them to blinding white temps and hold it for a half hour or so. Then again the mix I use is pretty low on fluxes, I am using more or less kaolin with some grog and fine sand. I noticed a big difference in half-fired and completely fired.

OddDuck wrote:
Well, that proves they do work. Just out of curiosity, do they ping when you tap the side or thunk? If they aren't fully fired they will be rather fragile and quite prone to cracking unexpectedly. The ones I have made I have tried to get them to blinding white temps and hold it for a half hour or so. Then again the mix I use is pretty low on fluxes, I am using more or less kaolin with some grog and fine sand. I noticed a big difference in half-fired and completely fired.after the first melt and before i went for a second it had a real ping to it like a china cup. i havent fired the rest yet as im going flat out on my new furnace.

im very happy with the crucibles but... they only last for one or two melts of brass.
i went through three pots today but i cast these.


they weigh 4.2 kgs which is the largest brass casting session ive done in one day. ive still got one rear wheel to get to complete the set. the crucibles had small cracks and as they they dont take much to make i decided not to try and grabbed another. i will experiment with different mixes soon...

the pics are great!
They speak for your ability.