Minwax Polycrylic question

[BartMan]

I'm in the process of refinishing my Fernandes Mustang copy. After reading about the Polycrylic being used as a grain filler and sanding sealer, I've decided to give it a try. Since I don't have a spray gun (and have no plan of getting one), I've been using foam brushes to apply it. At the moment, I'm on my 3rd coat of Polycrylic. But up to now I still can see the open grains. So please bear with me with these questions.

1. How many coats before I expect the pores to get covered?

2. I've flat sanded with 220 grits in between the coats. It seems like I'm just sanding off the coats. Even with light sanding, it seems like the grains are getting exposed over again. Is sanding in between application necessary if I'm going to use solid colors anyway?

3. Which is more effective for maximum coverage, brushing along the grains or across them?

4. Will it make a big difference if I also apply 3-4 coats of sanding sealer (Zinsser) over the Polycrylic during the final stage of the sealing process?

Thanks so much.

[Narco Martenot]

I have never used this as a grain filler, but I have used this a lot within the past six months as a clear coat. However, I have only used this in a spray form (they do make this in spray cans). I will help all I can:


1. I am not sure, but I'm going to guess two thick coats.

2. I usually lightly scuff the surface only, and I have never had a problem by doing it this way. Otherwise, you are just removing the existing paint. When you sand polyurethane, it reacts a lot differently than a typical lacquer/enamel. It kind of just peels off; so be careful.



I am not sure about your other two questions, but I am curious as to why you would want to put the Zinsser over the Polycrylic?

Sorry I can't be of any more help than this.

Also, the longer you let the Polycrylic dry, the harder it will get. When it is has cured, it is VERY durable. I think it usually takes about a week for it to fully harden, but I am thinking it would be fine to paint over this within a few hours as it dries so quickly.

[Dave]

I've not used this but using shellac sanding sealer I was applying a good 3 coats (and thick) before gently sanding down. Do a light sand over everything hold up to the light and the matt areas are sanded and the reflective show the 'dips' The ultimate aim is to sand everything matt (i.e flat) but without exposing any wood. I shoudl also warn you that its possible, depending on the product, that after a couple of weeks drying it will start to show grain again. It would be worth waiting after final flat sanding and checking again after this time. if it has then perhaps sand some more and if need be put another coat on.

I think 220 grit might be a bit too rough here...start off higher and increase the grit until it hits that happy medium of working but not too fast.

I'd probably brush on along the grain and across to ensure penetration.

If you use other sanding sealer on top the only difference is if the two are going to react badly to each other. Other than same story: Apply 3 coats, lightly sand back, check, repeat

[BartMan]

Great. Thanks, guys.