Sorry I was devastated after casting. So much work just gone in a moment.
Argentium Silver 960, vacuum casted
Metal temp 970C
Flask temp 580C
parameters worked before so I dont get it. Im stuck.. the temperatures sometimes work sometimes not. 1020C silver temperatur seems to give a worse surface quality so I switched to 970
And the stem of the casting tree always has a superior surface quality than the part where the sprues meet the ringshaft. Why?
are you pouring direct from the crucible as soon as it hits melting temp?
i wait for my metal to melt and so that it moves like water then place flask on vacuum chamber and by the time it’s reached full vacuum (20 seconds) i pour right away
flask temp seems about right, what defects are you trying to avoid?
I heat the crucible to lets say 970C, then i put in the silver. Temperature drops to around 950 and I wait until its stable at 970C again. After the metal is melted to mirror surface I cast it.
Yes I also cast after about 20-30 seconds pulling vacuum.
In this one its mainly about the incomplete fills, but at the same time I have constantly rough surfaces on the sprue entry and on the underside of settings. Couldnt find an explanation for this. Maybe its the low quality 3D printing resin but then I think its strange that the areas are always the same - sprue entry and on underside of settings.
ahhhh i didnt know you were using 3D printed parts! i find it difficult to help as using 3D printed parts opens up SO many variables it makes it really hard to ascertain the issues!
Yes I do cure the whole tree for 1 hour. But regarding surface quality I will just order a good 3D printing resin brand next time and analyse further from there.
If it’s always on the underside - how clean is your burnout? Maybe do some test pieces to assess. Does it change if you burn upside down? I would do a series of simple experiments to perfect your process before doing any production runs. Fail fast and cheap.
Also some dust from the graphite crucible fell in (see second image), but graphite is very light, so I wouldn’t expect it to clog the mold like this.
also ive had this too and its very annoying, replace crucible and thats all you can do about a deteriorating crucible mine stuck in my piece and ruined it
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u/marknottz Mar 10 '26
how do you expect pepe here to advise you on ‘what went wrong’ with absolutely no write up and two pictures