OK, this is driving me nuts. Am doing some sample boards using tung oil and varnish, with either mineral spirits or Naptha as thinner. Am moving away from the Naptha, I think, so let’s say just mineral spirits. On the 3rd coat, I started getting these little (and I mean tiny, tiny) bright/sparkly spots scattered across the surface. They vary in size within the “tiny” range. Looking at them under a magnifying glass, I can’t see any shape to them to give me a hint. I know I have some dust contamination, but can’t imagine this accounts for glittery stuff in the finish.
The materials are new — varnish and tung oil. Mineral spirits are pretty new, but not just bought.
There are a few pin-head size shiney spots too. I think those might be varnish coalescing around a piece of grit or dust?
Has anyone experienced this before????
forestgirl — you can take the girl out of the forest, but you can’t take the forest out of the girl 😉
Replies
Curious why you don't like naptha? MS takes forever to dry.
Sorry I can't help with the speckles problem.
Makes no sense to me to use a super-fast-drying thinner with tung oil, LOL! The Naptha is not going to hasten the drying of the tung oil; that can only be done with a cobalt dryer. I love Naptha but try to use other options when it doesn't really matter; Naptha is kinda nasty stuff.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Ooops, didn't specify the surface prep. I sanded to 220 grit, last pass was taken with the Norton 3X stuff. I then wiped down well with Naptha, which I assume would remove any stearate that might cause problems.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
forest girl,
your problem sounds like moisture/humidity/water as the culprit.
wipe the surface with alcohol and apply the next coat. good luck.
"moisture/humidity/water " Wow! I don't know how....it's been 22-23% RH in there since I started running the pellet stove regularly. I'll try the alcohol wipe though. Thanks.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I have also seen these shiny star-like spots after applying tung oil with mineral spirits. I have decided, not that I am necessarily right however, that this is the oil bleeding back out. When I use a tung oil/mineral spirits finish, I am usually doing a little wet sanding, especially with a very figured piece of walnut. As I finish the wet sanding, I wipe the sludge across the grain trying to fill any pores level with the wood. Sometimes I have to try again and again. As I wipe this sludge across the grain, I am also wiping the excess off of the work piece. I find that I will have to wipe it again at about 20 minute intervals as the oil bleeds back out. Usually 3 to 4 re-wipes I guess you would call it. Guess what tells me that I need to wipe again? Those tiny, shiny star-like spots you are seeing. The reason I check every 20 minutes is I have found that to be a safe time interval where I can still wipe them off. Once I check two times in a row and do not find any of the spots, I let the piece go ahead and dry.
I first ran across this when I was finishing a Turkish walnut shotgun stock that was very figured. I also had the same thing happen when I finished a drawer front made out of teak. Ditto on a piece of birdseye maple.
Now the good news is that if you get busy and forget to check the work piece and the shiny star-like spots dry so to speak, simply add more oil, wet sand, and don't forget.
Hope this helps.
Rusty
I'm usually pretty good at handling the bleeding thing (lots of practice, LOL). If this is bleeding, it's truly weird stuff, being so tiny. I'll try sanding it with oil. I tried just a bit of dry sanding one one edge of the test board the other night and it didn't do a darned thing.
Almost looks like someone scattered microscopic pieces of crushed glass, weird. Thanks for your post.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
i know silica is used in matte finishes. the silica might not be filtered enough? Just a thought to consider as well.
I'd check the two materials separately on a test board, and to be sure about bleeding make the test on something with fine pores like maple where the bleeding isn't likely to occur.
My only suspicion relates to the tung oil (I assume is actual 100% tung oil, not tung oil finish). I see that one of the tests mentioned when sellers describe the commodity tung oil they have for sale is one for crystalization, which is supposed to be negative (no crystals). I don't know the particular test, or how possible it is that a bad batch could occur, or that the bad batch would exhibit crystals. I've never seen such a thing myself, so this is a pure total guess based on only a hint of real information.
Wow, Steve, you may have hit on something. I Googled "tung oil test" crystallization and can see where there's a test related to crystallization. Unfortunately, didn't find any info on what the test is. But it's a clue! Thanks.
I bought a can of TO Friday that's a different brand, so I'll try that out. I'm thinking a test on glass might be a good idea, to eliminate the bleeding factor and see if it's just in the finish.
"make the test on something with fine pores like maple" That's exactly what this is, LOL. forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Sorry FG, as mentioned in the other thread where you asked my opinion on this I'm (at this point) drawing a blank on the cause and cure for your problem. If an answer comes in the next few days I'll post back here. Slainte.Richard Jones Furniture
"I'm (at this point) drawing a blank..." I was going to make a smart remark about you having more talent than to be drawing blanks, but my last attempt at humor failed dismally <g> so I'll not.
I'd sure love to get some info about this crystallization test. Guess I'll pop over to Jeff's place and see if he knows. Thanks for searching your mental archives, Richard. I do appreciate it!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Well, FG, I fire blanks, which I suppose is related, but that's because I decided after my one and only daughter whom I love dearly that I didn't want any more snot nosed little babies and children in my life and long ago went to see a doctor for the snip, snip, Bob's yer Aunty job.
Ironic really, now that the said daughter is pregnant with twins and likely to drop 'em in May or June. Oh, joy, two stinking snot nosed screaming little brats in one go. Luckily, home for the eager and anticipatory Gramps is a mere two hundred miles away so baby sitting duties should be minimal-- with luck. Slainte.Richard Jones Furniture
Oh, you're gonna love being a grandaddy! My hubby was dragged kicking and screaming into grandpa-hood, but it didn't take him long to be totally and irrevocably hooked!
BTW, he fires blanks too, but it doesn't seem to affect his drawing....ooo, too dumb to be funny. Speaking of drawing and gradchildren, the grandson showed us his plan for the fort he plans to build this summer. 3 stories high, pool on the second floor. A budding architect with lofty ambitions! forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Jamie, I suggest you get back to bare wood again, then apply some of the magic potion (Zinsser Bulls eye Shellac sealer dewawxed ), zap with fine wsteel wool when dry, then continue with whatever finish you are wanting.
Fortunately, I discovered this on scrap practice, not the workpiece. The only thing that's gone right with this project, LOL. I did my first application on scrap last night with new tung oil and a semi-gloss poly. Will see how that works.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Edited 3/14/2006 11:43 am by forestgirl
So,didya figure it out?What was it?
Well, no, but I went to the new tung oil and a can of semi-gloss poly instead, and I think that has gotten rid of it. I know, I know it doesn't tell me what caused the problem, but I don't have time for a multi-step experiment right now.
A friend of mine in California has a couple of chemist friends he's going to pass my questions along to (questions about crystallization test, and type of dryer that does or does not work with TO) and I'll get some info from them. After I get this project done, I'll spread a little of the suspect TO on a piece of glass in a sterile room ;-) let it dry, and see if it has "shinies" in it.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
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