Finishing conundrum

[chuck van dyck]

Hi all


I am finishing a project made of sapele plywood. Its a custom layup on 1” baltic birch by a renown local veneer shop.


I’m spraying GF high performance in satin. Well I got some runs and per usual I scrape the runs back with a card scraper. I thought I did a good job sanding afterwards to give a consistent scratch pattern, but apparently not. So I went back to 120grit and progressed back up to 220. Im still getting this super smooth spot that appears much darker than the rest. Maybe I just havent sanded back far enough? Its scary as these sheets were $700/pc for 5x10s. Any ideas? Maybe a chemical stripper to lessen the need for sanding…


Thanks for looking
IMG_8430.jpg

[Maurice Mcmurry]

My best guess is that you have gone trough all of the finish on that dark spot. I will have to google what GF High Performance Satin is. I would dab a tiny bit of finish on tiny area of the the dark spot and see what happens.

[chuck van dyck]

Thanks Maurice.

Its interesting because its almost like the opposite. The dark spot is the finish that was burnished by the card scraper… I think my only recourse is to find a similar patch and test there. Unfortunately there are a few spots where I used the scraper, some more hidden on the final product.

[chuck van dyck]

My best guess is that you have gone trough all of the finish on that dark spot. I will have to google what GF High Performance Satin is. I would dab a tiny bit of finish on tiny area of the the dark spot and see what happens.

Maurice, I take it back. Im not 100% yet that I have solved it, but it seems sanding further seems to solves the issue. Fingers crossed. Its gonna be a nerve wracking night.

[John TenEyck]

I've used a fair amount of High Performance and never experienced anything like that. I usually just sand off runs, but a card scraper should do just as well. My only guess is that you might have scraped/sanded into the veneer far enough that the bonding glue is starting to show itself. How thick is the veneer? 120 grit is fine on 1/16" shop sawn veneer but aggressive on commercial stuff.

John