# Confused On Mineral Spirits/Poly



## mattisthename (Jul 10, 2013)

Hey all.

I have done lots of small projects before, but this is my first significant effort. I have laid an nice walnut wood inlay strip in to maple. I stained it (natural) and then applied my first coat of semi gloss poly.

I read that I should sand (400+) then wipe with mineral spirits. I am using an oil based poly and an oil based mineral spirit. 

Once the 1st poly coat was dry (about 24hours) I sanded. There was one place on the inlay that the sanding seemed to leave a very light haze. I couldnt tell if it was sand, dust or scuff. The rest of the inlay did ok. So I decided to do the mineral spirits to clean. 

It wiped well for most of it, but the white haze took a lot of rubbing. I got maybe 80% of it up. Then I decided that whatever it was is not coming up, and that a second coat of poly should remedy it. So I dried it with a cloth and waited 20 minutes and applied the second coat of poly. 

My questions:

1) Will using the mineral spirits remove too much poly? I read some things that made me wonder.

2) Will applying oil poly over oil mineral spirits be OK?

3) I didnt wait long after doing the mineral spirits rub down (20 minutes?) Was that dumb? Should I have waited longer? It seemed dry to the touch.

Thanks for the help!
Matt


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## Fred Hargis (Apr 28, 2012)

2nd question first: Applying the varnish over the MS is OK. Worst case would be if it was wet it might the varnish would absorb it becoming , well, thinner. As for wiping the first coat with MS after the scuff sanding....the varnish may not have been cured enough to use the MS. I've some difference across brands with how quickly they cure. If they aren't cured enough, putting MS on them can creates problems; it redissolves the finish. My suggestion would be if you have to use a fluid to wipe it down after scuff sanding....use water. Then wait for it to dry completely before another coat. I'd also probably use a little coarser sandpaper for the scuff coat, but that's me. As for the haze, it may have just been a spot in the piece where the finish was absorbed into the wood, moreso than the balance. I wouldn't try to solve the problem on the first coat, apply the second and then see what you have. The first coat should completely seal the wood, which means the second coat should look much more uniform.


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## mattisthename (Jul 10, 2013)

Thanks for taking the time to respond Fred.

That all makes sense. So on the whole, it sounds like I should be ok in the end. The MS may dilute the poly, but I wont get any crazy bubbling up or anything. 

Whew. :thumbsup:


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## Bill White 2 (Jun 23, 2012)

If the poly is dry, MS will not damage it.
Just remember that "dry" and "cure" are two entirely different issues.
Let the finish cure before final rub out.
Bill


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## mattisthename (Jul 10, 2013)

Thanks Bill. I did not know this.


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## Rick Mosher (Feb 26, 2009)

400 grit is way too fine to sand maple before finishing with a film type finish. 180 is the finest grit I would sand the wood before finish. Burnishing the wood can cause finish adhesion issues. (The finish could peel off the wood later because it hasn't penetrated into the pores enough) Do samples before you work on your project to make sure everything works like it is supposed to.


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