Graphite crucible breaking down quickly

[Chalamba]

Depends on cooling cycles the most. If you cast like 3-5 flasks at a time, 20 castings will do with one cruicable.

[Wdshea]

we get our flasks from Rio. 10 cycles sounds about right.

i don't heat the flask to melting temp. i start off ~200* above whatever the melter is reading, for instance:

Temp 75*
i set it to 275*

then temp overshoots to 450*
setpoint -> 650*

then SP -> 850*

and so on till i get to melting temp.


i have achieved longer life using this method. eventually, the top of the crucible which i grab with "tongs" wears thin, so i use a drimel tool to cut a groove to prevent the tongs from slipping off. learned that the hard way.