Need resin for overlay work

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#1

Ok I think I need to find a different resin. I have been doing a lot of carbon overlay work lately and I’m currently using silmar 249 resin. I have noticed lots of microscopic air bubbles in the resin after cure so I think I need to find one that I can degas prior to applying and the silmar cures to quick for this.

I also don’t thing the polyester is saturating the fibers very well compared to epoxy is this because of the quick set times or a characteristic of PE?

I’d like to hear what others are using for carbon overlay work.
Thank you,
Erick

#2

Have you had any issues with poly bonding to ABS? Im trialing iso 7x later today.
My best results have been with Alchemie’s EP519/H50. Sorry it’s a UK product and probably of no help to you.

UPDATE: I did a test patch with the poly. I sanded it with 80 grit. It just peeled off in a similar way that hot glue peels off polypropylene. Shame because it was really clear and had good mechanics plus UV stability. Back to epoxy and clear coat it is then…

I will try Resin Research next, they supposedly have a UV stable epoxy. Spoke to a surfboard maker last week, he was saying that until recently UV stable epoxies were practically non existent, but that he’s made several surfboards with this Resin Research epoxy, and theyve been sat out in the sun for weeks with no yellowing or milking. Ill give it a try and post results.

#3

Curious to see that. If you like, I can toss a sample in our accelerated weathering rig (UV + moisture) for a week or so, or even longer, to see what the stuff looks like after a year or more in the Miami sun.

This offer is for anyone: At this moment we have quite some samples to test, so the rig is on 24/7, but there is plenty of room for more samples.

Samples should be 7,5x15cm (3"x6")

#4

My latest issue was with ABS and I was unable to get a good bond. I ended up buying the customer a new part. :frowning:

#5

I’ve been covering up some motorcycle parts with West System 105 & 206 this week. Seems to be doing quite well considering I’m a bit new to doing things this way. What I did learn about it (on my boat) was that gas bubbles are pretty easy to pop with a heat gun while it’s still syrupy. Makes it a little runny temporarily, and makes it go off quicker, but the end product looks fine.

try a heat gun? don’t mix it so fast? vacuum bag it? …just some thoughts…

todd

#6

I try not to do too much overlay work but since my molded parts cater to a smaller market I do my share of overlays. I only use epoxy and like the Raka UV Inhibited Epoxy System. Living in Arizona I tried a number of resins to find one that could hold up to our intense sun and this one has proven to do well and is pretty good to work with. I only use it for some of my smaller molded parts but almost always use it for overlay. You can see some my parts at roguese7ens.com/photos.

#7

Can you go epoxy then poly over the top to get a good bond and a nice clear with UV protection?Have you tried making really deep sanding marks?