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when cutting a mold for jewelry i am not getting all the details?

i am confused with this one, i have vented it (from a couple of times to many times) i am using a silicone rubber. the piece is only 1 inch but has a lot of writing on it. i have cured the mold properly. i have played around with wax temp. (i use a injectomatic) i have also done alot of different pressure tests. need help badly thanks

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jtobako7 years ago
Have you powdered the mold so that the trace of powder will hold open the vents so that the air can escape? What exactly do the flaws look like: bubbles, smooth/rounded edges, ripples? Are you at high enough pressure to start getting flashing around the edge?
seandogue7 years ago
As suggested by orksecurity, are you using a vibratory or centrifugal system to ensure the mold is being penetrated in the fine details and that air bubbles are released? you might also consider immersing the mold in a warm/hot-water bath to make sure that you're not cooling the outer shell of the wax template (where it meets the silicone mold) too fast.
How about microwaving it very gently for a couple of minutes post-pour ?
Not a bad idea, but I'm not sure how much heat the silicone will pick up, since microwave ovens are tuned to water. Conduction just seems an easier route to me...
I was thinking of keeping the wax liquid for a few more seconds, directly - waxes heat up beautifully in microwaves.
Ah...I see... yes...that makes sense. I thought you meant to warm the mold prior to pour...
orksecurity7 years ago
Uninformed guesses: If the problem's the mold: Make sure you get all the air out when making the mold.. and when you remove the object from the mold do so gently to make sure you don't take any details with it. You are using some sort of mold release on the object to avoid sticking, right? Make sure it's a sufficient, but sufficiently thin, coating. If the problem's the casting... again, is there a possibility of air trapped at the surface? (Vibrate the mold while casting, pour slowly enough, ...)