# Mineral Spirits vs. Paint Thinner



## djg (Dec 24, 2009)

I'm getting ready to stain my fiberglas door with a gel stain and the prep calls for wiping the surface down with mineral spirits. I thought I had a gallon around here, put all I have is paint thinner. Does paint thinner evaporate without leaving a residue like mineral spirits? I know they're both organic solvents, but not all sovents are the same. Has anyone used PT instead of MS this way? Thanks


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## woodnthings (Jan 24, 2009)

*pt vs ms*

Here Ya go: http://www.doityourself.com/stry/3-advantages-of-using-mineral-spirits-over-paint-thinner 
In brief ms is more refined and therefore more expensive.  bill


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## cabinetman (Jul 5, 2007)

I would use mineral spirits. Any residue would be compatible with an oil base gel stain. You might want to use a dry tack cloth like this before staining.












 







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## djg (Dec 24, 2009)

cabinetman said:


> I would use mineral spirits. Any residue would be compatible with an oil base gel stain. You might want to use a dry tack cloth like this before staining.


Thanks, but you were a little too late. Ok you weren't, I was too impatient and ill prepared. Man I don't care for that Gel stain. Kind of like that antiqueing process popular years ago. By the time I got the 2nd side done I had a fairly good method. I have to restrip the long stiles on the first side because I didn't do them as a whole. I did top section, then bottom section. But I'll try to blend it better first after it's dry. Anyway, the point of replying is this: when I tried to blend in the two halves, The areas became blotchy. The finish stuck fairly well to the surface despite using paint thinner. And I have previously scrubbed the door down with Simply Green and a nylon pad.


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## cabinetman (Jul 5, 2007)

djg said:


> And I have previously scrubbed the door down with Simply Green and a nylon pad.


Did the instructions say that stuff was OK to use for preparation to stain?












 







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## djg (Dec 24, 2009)

No it didn't. But after the Simply Green, I washed down the door with a generous amount of hot water and a rag to remove any possible water soluble residue. The door was pretty grimmy. Then I let it dry for 2-3 days and today wiped it down with the paint thinner. After I let that evaporate (ca 1 hr) I hit it with the gel stain.


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## cabinetman (Jul 5, 2007)

djg said:


> No it didn't. But after the Simply Green, I washed down the door with a generous amount of hot water and a rag to remove any possible water soluble residue. The door was pretty grimmy. Then I let it dry for 2-3 days and today wiped it down with the paint thinner. After I let that evaporate (ca 1 hr) I hit it with the gel stain.


I'm not saying that this happened in your case, but, with some regimens, it takes very little to cause a contamination. It may show up like yours or in other ways.












 







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## Even (Aug 4, 2016)

I have the same question about mineral spirits. I stained a garage workbench (has never been finished). After 4 days a very small area on the edge was still tacky. Shewin Williams tech support told me to lightly wipe down the area with mineral spirits but It took off some of the stain. After I let it dry overnight, I tried to lightly stain over that area but it doesn't want to take. I think the MS left an oil deposit and now I can't touch up the stain. How do I fix this?


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## Steve Neul (Sep 2, 2011)

Even said:


> I have the same question about mineral spirits. I stained a garage workbench (has never been finished). After 4 days a very small area on the edge was still tacky. Shewin Williams tech support told me to lightly wipe down the area with mineral spirits but It took off some of the stain. After I let it dry overnight, I tried to lightly stain over that area but it doesn't want to take. I think the MS left an oil deposit and now I can't touch up the stain. How do I fix this?


Are you working with oil stain or gel stain? You can't use oil stain like paint where you brush it on and let it dry. You have to wipe off the excess completely. Wood will only accept so much stain and it seals the wood in the process. I suspect all you did in wiping the wood off with mineral spirits is remove the excess sitting on the surface which should have been wiped off in the first place. An oil stain doesn't have a binder in it which will adhere to the surface. If the excess is not wiped off it will lay on the surface like dirt. Then when you varnish over it the varnish adheres to the stain instead of the wood and it the weeks to follow starts pealing off. 

If this describes what you have I would wipe the project down with lacquer thinner removing as much stain as possible. Then use an alcohol based dye stain to bring the color you desire back. The dye stain is more similar to ink and won't affect the adhesion of the finish you apply over the top. http://www.mohawk-finishing.com/catalog_browse.asp?ictNbr=178


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## Even (Aug 4, 2016)

I stained with Sherwin Williams oil based Wood Classics. I had the tint adjusted with more yellow if that makes any difference. It's a pine work bench and has been in the garage 10 years. I washed it with tsp and sanded it with 60 grit. It was in the low 80's when I stained and we have humidity but wasn't real high. By the time I finished the other side of the top (more than the 15 minutes in the instructions), there was little to take off. I did wipe it but it was so dry already, that I think I must have missed this little section on the bench.

I brushed it on with the grain then perpendicular to get it in the grooves and then finished with grain. I am concerned that stain in the grooves have retained heavy stain that may still be tacky. The lighter tones have some shine...don't know what that means. 

Does the mineral spirits not remove dry stain when wiped lightly so the stain that came off was the stain that never dried? I didn't wipe the entire top but when I wiped that which was dry, it didn't seem to produce any stain on the rag. 

Is there a way to just touch this area up without removing everything?


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## Steve Neul (Sep 2, 2011)

By sanding the wood with 60 grit paper it made it very porous. You pretty much needed to apply it with one hand while wiping it off with the other hand. Letting it sit for 15 minutes in summer was enough for that stain to dry on the surface hard enough that mineral spirits would do little to clean it off. At this point you pretty much need to strip it with paint and varnish remover. I don't think even lacquer thinner would do it. If it were me I would strip it and sand the wood to 180 grit and re-stain it. This time don't stain too much of an area at one time. Work about three feet lineal length at a time.


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## Even (Aug 4, 2016)

Are you saying that even though the stain has dried over most of the bench that it will fail with a polyurethane? If the wood was porous isn't that good for absorption? 

It may be hard removing the stain from the open grain. This grade of wood is more like what you find in framing and subfloors. Not high quality and not sure if I strip and resand it, if I won't be causing the wood to splinter. It was doing it a bit on the edges.

I guess if the whole bench is in jeopardy, I would strip and start over.


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## Steve Neul (Sep 2, 2011)

Even said:


> Are you saying that even though the stain has dried over most of the bench that it will fail with a polyurethane? If the wood was porous isn't that good for absorption?
> 
> It may be hard removing the stain from the open grain. This grade of wood is more like what you find in framing and subfloors. Not high quality and not sure if I strip and resand it, if I won't be causing the wood to splinter. It was doing it a bit on the edges.
> 
> I guess if the whole bench is in jeopardy, I would strip and start over.


I'm not there where I can see it but there must not be any dried stain on top of the wood. Stain is mostly pigment with a little linseed oil to hold it together to prevent the pigment from settling to the bottom of the can. The linseed oil isn't enough to bond the pigment to the surface. It's more like a layer of dirt on the wood. Then if you apply poly over the top it will adhere to the layer of dirt instead of the wood and peal off in sheets. I had a table in my shop one time someone sprayed on a stain pretty thick and just let it dry and then finished over it. I was able to pick one corner loose and peal the finish off the table like it was shelf paper. If the stain did absorb into the wood completely on your bench you maybe are alright however if the stain set for four days and not dried then there is probably stain on the surface. On new wood not wiping the stain off is the likely suspect. 

What you might do is spots that are especially dark you might try scraping the color off with your fingernail. If you are able to scrape some of it off then you have dried stain on the surface. If you are not able to remove any color then that is a better sign.


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