3d printed mold for silicon carbide
example of use: make a mix of silicon carbide powder (800 grit) and sodium silicate(10% or more, till there are no more dust coming off while mixing it with a power drill) for this you need ~400grams of silicon carbide powder.
use demolding agent or make the walls in contact smoother with sandpaper.
you can pack it with a long allen key, you put one spoon and pack it, then next spoon and pack it and so on. all operation are done with mold assembled. then you put in in oven at 60 degree for 1 hour. then remove inner part with a knife and put it another hour at 100 degree C
after this you wrap it in ceramic fiber and put in microwave oven 30-40 minutes, or until ceramic fiber stick to the crucible.
packing part is very important also drying part in the oven coz if not done it will crack
inner part probably need support i did not try without but it could work.
for second part to come off you gently smash it on a hard and stable surface like concrete floor of table, with the big opening facing downward till it will get out. if it doesnt that mean you add too much sodium silicate.
other binder beside sodium silicates can be used
also co2 can be used to harden sodium silicate but you still need to dry it after demolding in the oven. 200 degree or gas oven will crack it so better not try to speed up the process.
Use stp file for printing, much better quality.😛