What process/ resin used in this part?

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#1

Anybody ever seen a yellowish/ greenish resin like this? (It’s pooled in the corner)

This part was made by a manufacturer here in the states that makes alot of stuff for Nascar, and is venturing into the hobby industry. (This is a wing for an RC car) They claim there is no post trimming and you can see a parting line (on the right side of the pooled resin, where the straight edge meets- you can barely make it out), so they obviously used a multiple piece mold.

I’m intrigued by this part because it’s freaking STRONG. The infused wing I’m making is strong too, but it certainly has it’s limits. This thing they are making seems bullet proof, and it’s half the thickness of mine. LOL

I’m pretty sure the fabric is cut on a plotter, which kinda explains not having to trim the part after cure, and it definitely looks to be close molded. A friend of a friend thought they could be using a press to apply pressure to the mold halves. Anybody ever done something like that? If so, do the molds have to be billet? Or at least something more heavy duty than fiberglass and gelcoat tooling? Not sure of what kind of pressure is needed to do something like that.

It doesn’t appear to have been placed in a bagged open mold, then autoclaved as the finish on it looks like a fresh clear coat on all sides. No minute pin holes or imperfections in the surface at all.

Any ideas? I currently infuse all of my parts, but I just have to know how this was made!!

Thanks in advance,
Danny

#2

I say pre-preg. it’s the easiest material to cut and place exactly, using the right tools. Dry fiber is 100x harder.
As for the strength…many factors play a role. Resin, Layup schedule, and core material (or none). Even the SHAPE can play a roll. It might be shaped in a way that it reinforces itself (think flat panel, vs one with a raised V along one direction the middle. Won’t bend along that direction)
If closed molded, yeah, again pre0preg would work. If it is a production piece, I’m sure Al, Invar, or steel mold would be used.

As for the resin, many resins out there, many colors by default (Derakane 510a is clear greenish, while 8084 is clear dark green/brown, Polymeric SC15 is opaque white, Cytec 5250-4 is opaque yellow)

Can you ask them directly? Might provide some good clues on what they do, and give ideas on how to make it work for you?

#3

My guess is resin rich vinyl ester and the green puddling is the glue they used to hold on the fins.

#4

It does look like some sort of “glue” in the corners.

If you want a really strong room temp cure epoxy and color is of little importance… try West Systems. It sometimes cures with that yellowish-green hue, but the parts will be strong as heck.

#5

*** Cleaned up the thread. Please stay on topic, as people that find the site can get turned off by too much off topic info in threads.