Hotcoat Issues

I’m not an expert but getting good results by following advice here. I’m using epoxy.
Key the lam lightly with 120 paper, vacuum, blow off with compressed air with air filter, wipe with tack cloth, clean with dna, blow off, don’t touch. Squeegee down small amount and scrap it off, brush down fill coat. Hit with hot air gun several times with 5 min between. Turn off fans, heat anything that will churn the air.
After sending I do same on Gloss coat. But do hot air gun after 15 min

Hello Foil, 

Just reached your post in the archives, I’m having the same problem as you at hotcoat, I made a post about it, but would like to ask you if you find some solution for the tiny pinholes that appeared on your board.

Here my post:

https://www.swaylocks.com/forums/hotcoat-problem

***Hello, 

I’m having a problem with a polyester hotcoat, after I made the bottom of the longboard, pinholes started to appear in some areas. After sanding I’ll give a Gloss Coat, my concerne is that the gloss coat doesn’t cover this pinholes, as it happened on the last longboard I did. To solve that, I used some UV resin, but It was painful to cover each one of them (AHAH). So I would like to hear some opinions, to help prevent this, and if Gloss Coat doesn’t cover up, what’s the best choices I have. I found some good information in the archives, maybe it can be related with a lot of variables, like temp, humidity, outside/inside, mixing bucket… but would like to know a “fresh” opinion.

The board I’m working is a 9’4 longboard (6oz bottom and 2x 6oz deck) with a tail patch. Laminated with light grey resin tint.

I Hotcoated the deck first, and no problems with pinholes, just did a mixture of Silmar resin 249BB (1200kg* a bit more than necessary, as I have little experience* + 4% Wax in styrene + 2%Cat) and went OK.

I was proud of the deck hotcoat. After thar I made the bottom with almost the same quantities, just add a bit less Catalyst, because that day was hotter (20ºc in glassing room). So, 1200Kg resin +4%/48g wax in styrene + 1.75%21gr Cat. When I was applying hotcoat, at the beginning I passed the squegee over the board, to resin get inside. When finished, I started to see in some areas of the board pinholes appearing, I’ll attach some photos. I’m worried about that because last longboard I have done had the same problem, and cant find a reason for that.

I was thinking maybe should be the quantities of Catalyst, should put a bit more/less?

Can also be the way I mixed the resin, I had to stear well to mix with wax in styrene. After mixing it seems that the resin was not as translucent as before (I think it’s normal, even if you move slowly it happens);

Environment of the glassing room, I have a fan, but works really slow when hotcoating and its above my head, doesn’t directly interfere with the board;

Want to mention that the deck’s hotcoat went well, and it was with almost the same conditions. In deck I had the 2x6oz, at bottom 1x6oz, maybe have some dry areas there.

All advice is welcome, cheers!**

 

Thanks