Author Topic: Finish on pattern  (Read 9424 times)

PatJ

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Re: Finish on pattern
« Reply #15 on: November 26, 2013, 11:55:07 PM »
They make special releasing agent, which is just paste wax.
Johnson floor wax works just as well.

I wipe the pattern down with a light coat of it each time before I use it, and wipe off any excess.

Offline stevehuckss396

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Re: Finish on pattern
« Reply #16 on: November 27, 2013, 01:22:42 AM »
After some searching on the web and asking some more advanced founders the problem might lie in the enamel coating. I am not the only one having the sticking problem believed to be from enamel coating. There are some special coatings that can be used. Others have had good luck with varnish and some lacquer coats. I guess they dry to a real hard shell finish.
Do not be like the cat who wanted a fish but was afraid to get his paws wet.

Offline ART

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Re: Finish on pattern
« Reply #17 on: November 27, 2013, 01:51:20 AM »
Steve, There might be some solvent reaction between the petrobond ( alchol) and the enamel on your patterns which cause the sticking. I, also, use petrobond, and all of my patterns are coated with clear shelac then rubbed with 000 steel wool, then re-coated with krylon red primer. The patterns are re-rubbed with 000 steel wool again then used for casting. The "NEW" Krylon paint in the cans with a tapered cap are enamel. The "OLD' paint with the straight caps were laquer which worked very well, but not now. ART

Offline Jo

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Re: Finish on pattern
« Reply #18 on: November 27, 2013, 07:29:55 AM »
 :headscratch: If it is a solvent reaction would the use of acrylic car paint not be better?

Jo
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Offline Jasonb

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Re: Finish on pattern
« Reply #19 on: November 27, 2013, 07:43:57 AM »
Best talk to the foundry Jo to see what they prefer depending on their sand and moulding methods. John Winters sell the traditional red pattern paint.

Offline Dave Otto

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Re: Finish on pattern
« Reply #20 on: November 27, 2013, 04:28:02 PM »
I have only done a few patterns and they were all painted with two part polyurethane automotive paint. I didn't have any complaints from the foundry and the castings came out great; so I guess it was ok.

Dave