|Forum topic by Peter Oxley||posted 1895 days ago||758 views||0 times favorited||16 replies|
1895 days ago
In addition to staining or dyeing, I often color projects by tinting my varnish with stain. This avoids problems like grain reversal and over-coloring, while giving a subtle glaze effect. I’ve done it dozens of times without any problems.
This week I had problems. I had put down two coats of clear varnish without any issues, and put colored varnish on 80% of the project without any issues. But when I put on the colored varnish on the last four doors, I got dots. When I am pressed for time, sometimes I try to solve problems in ways that I’m sure won’t work: when the coat of colored varnish cured, I put on a second coat, hoping to cover the dots. What I got was a piece that was way too dark and the dots were even more obvious.
The only thing I can think is that, since these were the last few items, they may have had a little overspray from the previous parts. But if they did have some overspray, it would have only been there for a couple of minutes. I would think it would just mix/blend when I put down the coat of varnish.
I’m sure it wasn’t silicone – I don’t use it in the shop specifically because I want to avoid this sort of thing. And I’m pretty sure it wasn’t dust nibs in a previous coat because I scuffed before spraying (the dust you see in the photo is there because the photo was taken in the sanding area, not in the spray booth).
Eventually, I removed all the varnish with a scraper and sandpaper and started again.
So the question is … have you ever had this happen to you, and do you know what causes it?