Mineral Spirits is cloudy? Is this causing problem of poly not drying?

[Linnea Lahlum]

I noticed this container of Mineral Spirits I had around (in the attached garage) was cloudy when I poured it out. I’d never seen that before, so I checked the label and saw it was “odorless”. I thought that maybe that is just the way it looks. I used it as normal for cleaning off wood after stripping then cleaning my brushes after staining. The can I poured for cleaning my brushes did clear after a while.

I waited 2 days after staining. Then last night I did what I normally do, and blended 2 kinds of polyurethane together, satin and semi-gloss (because I like a finish half way between the two). Then cut it with about half mineral spirits, to make it dry faster. I do this to reduce the dust that falls into the surface. This is no different from what I’ve done many times before. Both cans of finish were new and stirred thoroughly. The cloudy mineral spirits makes it look like butterscotch in the jar.

I checked about 12 hours later, to see if it was ready for sanding. To my surprise, it was still tacky. So I turned the dehumidifier on,which has been off since the heat was turned on (midwest, Chicago area). Turned on a swing-arm incandescent lamp to provide a little mild warmth. A small fan a few feet away. I just checked again: no real difference, 7 hours later. I had even brushed a thinner coat than usual. I have never had half strength poly not dry to the touch really quickly, so to be able to recoat the next day if not earlier.

I don't think it's a problem with the stain I used (Oil based, brushed on, wiped off 20 minutes later. Same ones I have used before.). All 3 had different colors of stain. The two oak pieces are tacky. One had one coat of stain, the other 2 coats. The walnut table top (1 coat of stain) is slightly drier. Unless the 2 days I allowed were also not enough.

I don’t normally finish at this time of year. But I avoided rainy days. I misplaced my humidity meter, which I normally check before finishing.

What do you think? Humidity that was higher than I thought, or something wrong with the mineral spirits? Will I need to remove the finish? I hope not, as I don't want to damage the stain job. Thanks.

[Wayne Lomman]

The spirit is most likely contaminated with water. You are probably going to have to do it all again. Sorry I have no better advice. Cheers

[Steve Eure]

I bought what I thought was a bargain jug of mineral spirits from wally world last year that was white and odorless. Instead of mixing it, I asked about it on this forum. I was advised not to use it to mix, but for brush cleanup,etc. Thats all I've done with it. My finishes are too important to ruin with bargain basement ms. Too me, the finishing process is the hardest part of my projects, and at times either makes or breaks the work.
I don't have a answer for you as far as time, wait and see if you have it, or sand and start over.

[Linnea Lahlum]

Thank you both. My husband had thrown outmy mineral spirits, and I made him go out and buy a new can. It came in a plastic jug, which I thought wasvery weird to begin with. I would nothave chosen one that claimed to be odorless. I thought maybe it had frozen out in the garage.

This is upsetting. I have already investedmuch time into refinishing these pieces. I’ll give it some time first, and hopefor the best.

[John TenEyck]

Sorry, but I doubt it's going to turn out OK. You can try turning a fan on it, but if it doesn't dry in another day I think you'll have to strip it and start over.

Odorless MS is completely unsuitable as a thinner for clear finishes. To be perfectly honest, I think it's unsuitable for anything related to wood working. What you want is 100% mineral spirits, sometimes sold as "paint thinner".

John

[John K Jordan]

Sorry, but I doubt it's going to turn out OK. You can try turning a fan on it, but if it doesn't dry in another day I think you'll have to strip it and start over.

Odorless MS is completely unsuitable as a thinner for clear finishes. To be perfectly honest, I think it's unsuitable for anything related to wood working. What you want is 100% mineral spirits, sometimes sold as "paint thinner".

I've read the same thing on other wood forums. I'm careful not to buy the odorless now.

And maybe time to train the hubby! Or send him back to the store with written instructions. My Lovely Bride is not allowed in the shop without a guide. And I'm not allowed around her culinary supplies. (just kidding, of course!)

JKJ

[Conrad Fiore]

I have been using Klean-Strip Odorless Mineral Spirits for years and have had none of the problems listed above. The SDS lists the components as follows:
Hydrotreated light distillate (petroleum) 100.0 %

[Linnea Lahlum]

Thanks. Sigh....

I have only ever stripped pieces where I was doing a total refinish (like I started out with these pieces in the first place), trying to get down to as bare a wood as possible. This always ended up removing any stain as well.

If I go back to using my stripper, do I need to re-stain as well? I ask because I did a very finicky staining job, applying extra in some areas, to even out lighter, less absorbent areas, etc.

Or, because it's still tacky, is there as easier way to remove the poly?

[John TenEyck]

You can try removing the sticky finish with some real mineral spirits. If all the stars are aligned, the finish will come off but the stain won't. I'd rate the probability of that at less than 25%. If you have to strip it the stripper will likely remove the stain, too, especially if you used a typical oil pigment based stain. Sorry I don't have a more optimistic outlook on this.

John

[Linnea Lahlum]

I decided to rub one of the pieces down with mineral spirits and see what happened. I’ve got nothing to lose at this point.

I got quite a bit of finish off on a rag. It immediately lost the tackiness. I’ll have to see what it’s like after it dries. Some of the stain came off as well. I don’t usually rub down pieces with mineral spirits after staining, so I don’t know if that normally would have happened. It's a red oak stain, so red might have come off anyway.

The stain coming off made me think that possibly the stain was not fully dry before I applied the finish…? Though I had left it for 2 days, which would be usual, I likely did not take the high humidity into account. It’s only slightly lighter than before. I had stained it to match existing furniture in the room, so it no longer is quite dark enough.


I put a humidity meter in the room. It started at 75%, and it has not gone below 70%, even with the dehumidifier running round the clock. I am really surprised it is that high, considering the forced air heat is on. I am keeping that room closed off. It did rain all day yesterday.