Ski Builders Forum

Has anyone else worked with Isosport's ICP 8210 clear topsheet material and had bonding issues? I'm using it for the first time on a pair to put graphics on top of a veneer topsheet (and protect the veneer). I just pulled the skis out of the press (vacuum bag) and though I haven't trimmed them out yet, when I tested the bond along the edge, I'm able to pull up the topsheet just using my fingernail. The cores aren't cut to shape (that'll be done as part of the trimming process), so where I tested isn't part of the skis.

The only topsheets I've used so far, I've gotten from CODA and the bond side is pre-prepped (it's almost "hairy"). If I sanded the bond side of the 8210 though, I'd think the clarity would be lost....

On the positive side, for previous skis I've been using epoxy to finish veneer topsheets after pressing and trimming, but it's a very labor/time intensive process. Sandwiching a layer of epoxy between the veneer and a peel off plastic sheet seems like it could be an easier/better way to get a nice smooth epoxy finish on the veneer during pressing.

Scott

I get a really nice smooth top on my veneers using just parchment paper. For me the trick is to adhere the parchment to the top Alu skin with spray adhesive. Make sure it lays nice and smooth on the Alu and somewhat tight. As the pressure is applied it will put some tension on the paper which helps to flatten it. I've had no wrinkling issues doing it this way.

Then I do some light sanding and finish with 2 brush coats of spar so it builds up quickly and 2 spray coats. I sand lightly between coats with 220-400 grit. They come out smooth and glossy for me this way.

i do it the same way as vinman described. works rellay well!!

Thanks Vinman and Chrismp. Good tips for the future. For this pair though, I wanted to overlay a graphic on to the veneer, which was the main reason for using the clear topsheet (with the graphic printed on the underside). Seemed like a better way to do that and also avoid the extra time/work of multiple coats of SU and sanding..... BTW, the graphic only covers a small portion of the underside of the topsheet and where I tested the bond, there wasn't any ink that might have caused issues.

Scott

you sure you put in on the right way? easy to screw it up with that iso slear. It has a peal ply application tape and its tough to tell what side is down.

I did a test with straight 8210 and some I flamed prior to layup.
The bond was good with the straight 8210 but better on the side I flamed.

Yeah, I peeled back the protective film on one of the corners a bit before pressing just to make sure I could easily tell up from down.... Flame treating wouldn't have been an option as I'm pretty sure it would have screwed up the graphics (printed on the underside).

I haven't cut/trimmed the skis out yet, so hopefully after beveling and chamfering the sidewalls, it'll hold alright. I'm also going to finish the sidewalls with epoxy and spar urethane, which will overlap the edge of the topsheet and should help.

Scott

Did anyone solve this issue? I am having the same problem.

Clean & flame. Never had this issue.

Are you laying the ICP directly on the veneer? I believe this might be the issue. Getting two stiff, relatively resin phobic sheet goods to bond directly to eachother in a dynamic situation like this is a challenge. Adding fiber inbetween would help. Perhaps a very light fiberglass veil would help?

I never had any issues bonding them. Material is PA12, which should bond decently without preparation. But as far as I know the bonding side has been corona treated to further improve bonding.

Are you bonding the right side? The top side has a protective film on it which releases easily......

Protective film not always on 8210, depends on your order!

I flame the clear topsheet before layup. No issues. Use plenty of epoxy, more than you think you’d need and take the time to push air bubbles out towards the edge of the layup.