Author Topic: Mini Tutorial on Investment Mold Making  (Read 1088 times)

Offline Ron Scott

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Mini Tutorial on Investment Mold Making
« on: January 09, 2022, 09:09:41 PM »
I had posted a photo of a pistol butt cap yesterday , received some question and decided to share some on my experiences. I teach a seminar which utilizes cast mounts derived from original Flintlocks, so having authentic form  and high detail are desired. I make the frames from cabinet grade plywood scraps cut and assembled to approximated the shape of the part. The molds should be as smooth as possible and surface sealed. The mold pictured shows the transparency of the mold, enabling a clear view to cut out the original master. This mold is complex in that a pull core is used to make the ramrod pipe a tube. I am using a Shore 50 (firm) rubber from PolyTech. It enables me to use a higher PSI for wax injection, without deformation. I use a 60 PSI pressure chamber to cure the rubber. This reduced all bubbles to microscopic size. This wax is a new product to me. It has a good memory and is much less brittle than some I have tried. Not having a foundry available nearby, I have to carefully package and ship my waxes, hence the need to a non brittle, flexible wax.

I am sure there will be some additional question, so fire away.






Offline Carl Young

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Re: Mini Tutorial on Investment Mold Making
« Reply #1 on: January 09, 2022, 09:38:06 PM »
Thanks for posting this Ron. I understand your process, did similar though more primitive process back when. I find your work to be inspirational, as I am sure many others do.

Best regards
Carl
Already long ago, from when we sold our vote to no man, the People have abdicated our duties; for the People who once upon a time handed out military command, high civil office, legions — everything, now restrains itself and anxiously hopes for just two things: bread and circuses. -Juvenal

Offline okieboy

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Re: Mini Tutorial on Investment Mold Making
« Reply #2 on: January 09, 2022, 10:12:14 PM »
 This is very interesting.
 Since you ship your waxes to a foundry for casting, how many do you have to do each batch in order to get a reasonable casting price?
Okieboy

Offline Ron Scott

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Re: Mini Tutorial on Investment Mold Making
« Reply #3 on: January 10, 2022, 12:08:21 AM »
The foundry suggested they would like 100 pieces to be cast of the same alloy. They have been somewhat  flexible about the number

Offline moodyholler

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Re: Mini Tutorial on Investment Mold Making
« Reply #4 on: January 10, 2022, 06:00:36 PM »
How are you injecting wax into mold? Thank you for your time?

Offline Ron Scott

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Re: Mini Tutorial on Investment Mold Making
« Reply #5 on: January 11, 2022, 04:58:56 AM »
I have a small wax injector purchased fro Rio Grande Jewelers supply about twenty years ago. Used compressed air. I find 3-5 PSI works well for most of my work.

Offline moodyholler

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Re: Mini Tutorial on Investment Mold Making
« Reply #6 on: January 11, 2022, 05:22:23 AM »
Thanks!