# Can mineral spirits spoil?



## Thairiam (Mar 1, 2012)

I have two Christmas Bandsaw boxes I planed to ship cross country by tomorrow. (Needless to say I'm rushing.) Anyway, last night I decided to remove the sawdust with MS as preparation for a light application of shellac Seal Coat followed by several coats of canned spray lacquer. This morning the boxes and drawers are still mostly dark from unevaporated MS! I left a very small amount (teaspoon) in a tuna can on my workbench. It also hasn't evaporated! It was cold for here last night at around 40 degrees. The boxes I brought inside the house so temp shouldn't be an issue.

At the moment I have everything as near to an electric space heater as possible in hopes of drying them. I've decided to skip the shellac and go right into the lacquer application to save time.

If the boxes aren't completely dry of the MS and I spray am I asking for trouble?

If they won't completely dry would applying the Seal coat be an option?

Thanks for any suggestions.
Rich L.


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## mrbob (Nov 3, 2016)

You can seal coat them, one finishing method is wipe wood with BLO, wipe off any excess, seal coat right over it.


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## Kazooman (Jan 20, 2013)

I have never seen this with any I have used. Either your mineral spirits were somehow contaminated (by pouring something back in the can) or it had an unusually high percentage of unsaturated hydrocarbons and air oxidation may have led to some polymerization. Another possibility could be that the can was not sealed well and the more volatile components evaporated leaving a greater amount of higher boiling components than usually present.

I would hesitate to put any finish on over the gunk if it is not completely dry. I would get some fresh mineral spirits or lacquer thinner and wipe the boxes down well to remove whatever is stuck on them.


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## Kazooman (Jan 20, 2013)

> You can seal coat them, one finishing method is wipe wood with BLO, wipe off any excess, seal coat right over it.
> 
> - mrbob


If I recall correctly, boiled linseed oil is a drying type finish that contains metallic catalysts to speed up the oxygen catalyzed drying process. The BLO that penetrates the wood would continue to "dry" even after applying a seal coat. The finishing technique you mentioned does work well.

Unfortunately, there is no way to know whether the gunk that Rich has on his boxes will ever dry. Putting a seal coat or lacquer over it may lead to a real mess.


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## wapakfred (Jul 29, 2011)

Mineral spirits do not spoil, but I suppose you might have contaminated your supply in some way. You might want to take a piece of scrap (same wood as the workpiece) and try your MS, then shellac (or lacquer) on it to see if the finish dries, those dry so fast it wouldn't be too much effort to test.


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## Thairiam (Mar 1, 2012)

Actually there is no gunk. The wood is just darker/moister where the MS penetrated. I decided to try a heat gun on high setting to try drying the parts and after quite some time they did dry. However in many areas it continues to weep back out of the wood!

BTW I got the MS from a neighbor that was moving and the can is about one year old also; So guesses of contaminated or partly evaporated MS could be possibilities. Either way, lesson learned. No more products that I don't buy and control myself!

If i try the BLO/Seal Coat method are you saying to put the Seal Coat right over the freshly applied BLO?

Thanks for the replys


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## mrbob (Nov 3, 2016)

> Actually there is no gunk. The wood is just darker/moister where the MS penetrated. I decided to try a heat gun on high setting to try drying the parts and after quite some time they did dry. However in many areas it continues to weep back out of the wood!
> 
> BTW I got the MS from a neighbor that was moving and the can is about one year old also; So guesses of contaminated or partly evaporated MS could be possibilities. Either way, lesson learned. No more products that I don t buy and control myself!
> 
> ...


I was useing that as an example, that you could put the seal coat over your still wet MS.


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## JAAune (Jan 22, 2012)

> BTW I got the MS from a neighbor that was moving and the can is about one year old also; So guesses of contaminated or partly evaporated MS could be possibilities. Either way, lesson learned. No more products that I don t buy and control myself!
> 
> - Rich L.


He may have used it to do cleaning then poured the leftover solvent back in the can. It's certainly best to use only new solvent for critical tasks and put the second-hand stuff to use in general cleaning where it can't cause any harm.


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## MrUnix (May 18, 2012)

Mineral spirits (and most other solvents like acetone, naptha, etc…) do not have a shelf life unless you leave the container open and it evaporates. But based on your description, it sounds like you used way too much, as it should not be 'weeping' back out of the wood. Did you flood the wood with the stuff? All that should have been needed is a rag dampened with it (not dripping wet) to wipe it down and remove any remaining sawdust or contamination that may still be on the wood.

Is/was the MS clear? If so, then it's probably fine. Try wiping a thin coat on another piece of wood and see what happens. As for your current problem, you probably just need to give it enough time to evaporate off completely.

Cheers,
Brad


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## OSU55 (Dec 14, 2012)

Try wiping the wet areas with naptha, it should remove the heavy volitils from the surface. Continue using the heat gun to help dry it out. I would not put any finish but ob varnish or poly on unless you can get it dry. Next time if you are going to coat with shellac, use dna. If using an ob varnish naptha is better than ms - faster evaporation. I use micro fiber towels dry with excellent results.


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## Dark_Lightning (Nov 20, 2009)

Mineral spirits should evaporate within minutes. That 40 degrees may change it a little bit, but I'll bet that you have contamination. One of my neighbors moved awhile back, and gave me a gallon of MS that was in a rusty can! It works just fine.


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## ScottM (Jul 10, 2012)

Try bringing the boxes indoors for a bit to warm up and see if that helps the evaporation. Would at least narrow down what's happening; weather or bad MS.


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## Thairiam (Mar 1, 2012)

Thanks everyone for your responses. I did finally get rid of almost all of the problem. A few small spots kept weeping from the bottom of the drawers but time was running out so I took a chance and sprayed them. They came out OK I think. I'll post some pics on projects. I'd love to hear opinions, good or bad.


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