How should I cast these clips?

General Composites Discussions Composites Talk
#1

I think the only way, besides CADing and printing these damn clips, would be to cast them in a filled toughened resin, using silicone. All of which I have.
Drawing is crude, but I was thinking making a box around each clip, and then filling half way, to the green line, or to the top of the “cup” support. Add release, and then fill up the rest of the box. That will give me a two part mold. Seems like it SHOULD work…

#2

You will need to cut open the top part, but it might indeed work.

For releasing silicone from silicone, petroleum jelly works good.

#3

I’m interested to know how it turns out. Please keep us updated.

#4

wire edm comparable clips out of aluminum sheet.

#5

Printing might be the best, might not be strong enough.

Or wire edm some comparable clips from aluminum.

#6

I smegged up the pour because my silicone is old and was VERY VERY VERY thick. That or the schmuck who used it last added the thixotropic additive in the Part A of the silicone :-/ So there were many holes, even after degassing the silicone WHILE it was in the part cup!!!

Still, I got a 5min epoxy test part…without the top clip. I injected it before the hole filler (red) was fully cured. And I think the whole top section is a smeg up anyway. Will be ordering new silicone ASAP and redoing it.

#7

how resistant are, made with only resin? I tried with only resin and the piece has not a resistence (about 1 or 2 mm thickness).
I tried with a 1 layer of 160 gr glass inside and it’s more resistant

#8

I squeezed the sides together, and it was very tough. I didn’t try to break it though. I plan on using either a 3M 8115 epoxy, or making my own with milled CF fibers, or even just cab-o-sil. They only need to be moved a few times. I bet even the 5min epoxy is stronger than the ABS plastic ones :slight_smile: I’ve had enough plastic clips break off during normal use.

#9

Is the 3m 8115 epoxy good for certain applications? Just wondering why you’re choosing that particular one.

#10

I have it, along with mix tubes and the gun :slight_smile: This way, I can inject the resin in the vent hole I made, instead of trying to fill it up by pouring it in.