They are caused by ejector pins. Moldings don’t automatically eject from the dies and have to be pushed out. I agree they can be a pain, especially in older dies where you can find flash standing normal to the surface, which has to be shaved off.
From: STMFC@yahoogroups.com [mailto:STMFC@yahoogroups.com]
Sent: Sunday, August 07, 2016 12:44 PM
Subject: [STMFC] Circles in Plastic Castings
Just a question here. Nothing we can do about it except fill them in but, why are there small circular holes or impressions in various plastic castings? They can't be for material-flow in the casting process ???
As example, I have several Proto 2000 War Emerg. hoppers (and other kits) with these holes in the interior slope sheets, etc. Will have to file/fill them in. Just curious. What are they really for? Would be nice if they weren't there.
Thanks, Paul Hillman
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