Message Thread:
Varnish dis coloring wood
9/4/15
Website: http://granarywoodshops.com
HELP. I stained a table with two coats of min wax oil based stain. Dried two days. As I am applying oil based varnish, the wood is almost bleaching or dis Coloring! What's happening? Pic attached
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9/4/15 #2: Varnish dis coloring wood ...
Are you saying that the light areas where as dark as the darker ones before you put the varnish on?
9/4/15 #3: Varnish dis coloring wood ...
Website: http://www.awwtx.com
Your first mistake was using minwax, the stuff is pure junk. Your second mistake was trying to do a second coat, it doesn't adhere.
What "oil based varnish" are you using and how are you applying it? If you are brushing polyurethane, the finish will lift. You really need to use a better quality stain (we use dyes almost exclusively) and learn to spray your finish.
9/4/15 #4: Varnish dis coloring wood ...
Yes, Jeff, the discolored light areas were just as dark.
I've been using Minwax stains and Varathane varnishes for 20 years with great results. Glad that your dyes work for you. Thanks for your "useful" opinions Bill, lots of help.
9/4/15 #5: Varnish dis coloring wood ...
Website: http://www.awwtx.com
I do a lot of work with reclaimed materials, we are currently working on 12 tables made from 200 year old long leaf pine. Minwax stains are pitiful, especially on pine.
The finish lifted when you brushed the poly on, plain and simple. That won't happen when #1 you use a quality stain and #2 you spray the finish.
Sorry if a truthful answer to your mistake isn't "useful".
9/4/15 #6: Varnish dis coloring wood ...
I appreciate your effort to help. You've seen my website. All of f that furniture, 20 years worth, has Minwax stains. I am complimented all the time. I'm not a rookie.
The finish cannot have lifted as it was just applied. I, and a couple hundred years of woodworkers have used brush finishes when spraying is not an option. There are more ways to skin a cat than the one you like. So thanks for trying, but I need more thoughtful advice this time.
9/4/15 #7: Varnish dis coloring wood ...
Website: http://www.awwtx.com
Well, I've only been at this for about 40 years and I'm still learning.
This is a customer approval sample, one coat of spray no wipe dye and 3 coats of conversion varnish on longleaf pine. Dye can be top coated in 15 minutes, cv is blanket ready the next day. You will never get that depth or clarity of color with stain, especially minwax. If brushing is a necessity, the dye will never lift like stain will.
Best of luck.....................
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9/4/15 #8: Varnish dis coloring wood ...
I don't think there is anything wrong with Minwax stain per se. It is what it is - common oil stain.
If you let it dry for two days that should have been fine.
If the finish lifted there might have been something going on with your reclaimed wood.
Is it by chance yellow pine?
I have used some in the past that was so resinous that I can't imagine any finish sticking to it.
Almost like tring to finish oily Teak without something like shellac to try to seal it first.
Being a finishing snob is not going to help you figure out what is going on here.
9/4/15 #9: Varnish dis coloring wood ...
Tim, there really is no place for the Minwax to go but into the Varnish your applying.
As you were applying the varnish was the color beginning to disappear, or did everything look OK at first and then the color disappeared sometime later ?
Could it be that you did some extra sanding on those bald areas and the wood was to smooth for the color to absorb ?
Minwax is a tricky stain due to the oil content. Sometimes it takes days to really dry up enough to allow a coating to be applied.
Whats the weather like in your neck of the woods ?
9/4/15 #10: Varnish dis coloring wood ...
Robert,
It's been very humid in MN. That's why I went with a 2 day dry. It's 100 year old weathered pine, I have made many tables from this wood. It's soft, still pretty porous wood, but gives the rustic look my clients like.
The stain looked fairly/regular even before varnish. I'm fairly certain this is not a lifted finish...the coloring happened in the first 10 minutes of application. Not immediately, but slowly began over course of 15-30 min dry. I'm varnishing outside, in the shade.
My suspicion......is that I applied TOO MUCH stain in the corse of staining in the first place. Again, very soft pine. The legs are white pine from tablelegs.com and have some of the same affect happening. I'd did use a heavy brush coat, twice to deepen color. I suspect there is "some reaction" happening.
9/4/15 #11: Varnish dis coloring wood ...
I wouldn't call it a lifted finish but a lifted stain. If the Minwax wasn't stirred up real good the colorant may have sunk to the bottom of the can and you may have just been staining with oil.
Just guessing...so I apologize for what may seem like " gotcha questions " but they are not intended to be.
Mostly use dyes but on the occasion when I did/do use an oil stain I would always place my thumb on the surface for a few moments and when I removed it if I saw any oil bleed on the surface, I didn't consider it cured enough to continue with a coating.
Hope you figure out a solution...keep us up to date.
9/4/15 #12: Varnish dis coloring wood ...
Website: http://www.awwtx.com
Reclaimed pine, especially longleaf, is exactly why we transitioned over to dyes. Even as resinous as longleaf is, dyes will give a far more consistent coloration without the muddiness stains will cause.
There are much better wiping stains available than minwax. We use Valspar, Sherwood, and Mohawk. Given the caliber of Tim's work, it deserves a better finish than minwax.
Not exactly sure what a "finish snob" is, but last time I checked this is a PROFESSIONAL Finishing Forum. The idea being we help each other get better and that includes sharing new ideas and techniques.
9/4/15 #13: Varnish dis coloring wood ...
Can you explain the steps you used to prep the wood? While minwax is not the greatest, what you are seeing is not a stain performance problem but rather a prep or application problem and by saying this I am not saying you are not competent in any way.
By just looking at the picture the two things that come to mind that I would look at first is whether the stain was applied heavy, not wiped off and when brushed the varnish redissolved the layers of stain in areas and pulled it off. The other would be if the lighter areas still had some prior finish in the fibers that prevented the wood from absorbing the stain.
If you could post your sanding schedules it would give us a better idea.
9/5/15 #14: Varnish dis coloring wood ...
I've had bad luck with minwax so I don't use it anymore
Minwax takes way too long to dry and some colors needs several days for it to really dry
But if you really want to use minwax I would spray a sealer after the stain
Then sand it then top coat
You shouldn't have any problems
But I would look into other products if I were you
Mohawk has some really good stain
Give it a try
BTW I do not have as many years of experience as you do but I'm still learning
9/5/15 #15: Varnish dis coloring wood ...
I'm not so sure about the stain lifting or re-dissolving into the varnish. Where did it go if it lifted? I don't see any evidence of any stain in the varnish? It wouldn't be that clear if some of the stain was in it since it is a medium color. The light areas are almost white. Blushing wouldn't be that transparent either.
When looking at the one of the light spots, I see what looks like a machining pattern. It could also be a pattern that is left from corrugated cardboard. Did you possibly cover the top at some point with cardboard? They could also be marks from a wide belt sander. Just wondering because cardboard can have a wax coating on it and it can transfer possibly causing the stain no to adhere.
I know this doesn't help you but I kind of like how it looks.
9/6/15 #16: Varnish dis coloring wood ...
I see what Jeff is talking about ; but to me it looks like mill-marks from a knife planer . any chance the dis-coloration is only evident in the areas containing mill-marks ? perhaps machine glazing prevented stain penetration ?
was excess stain wiped off ? or built/layered and allowed to dry without removing the excess ??
i used plenty of minwax products back in the day....never had a problem . brushed their varnish over their stain ; ragged on gel varnish ; sprayed pre-cat ; probably even waterbase . .....no problems .
9/6/15 #17: Varnish dis coloring wood ...
Tim,
It looks like a contamination problem.
What was the source of the wood?
Minwax may be an inferior product; however, it certainly does work the vast majority of the time.
Other than it taking forever to dry, chronically lifting into the topcoat and the large particle size, it does change the color of wood.
Bill is being way to harsh.
I've known many fine craftsman who used Minwax when it was the only thing readily available. I among them when I was green.
9/6/15 #18: Varnish dis coloring wood ...
Thanks for all your help! While not digressing into brand battles....I am open to theories. I'm sure it's either what I did...how I did it, or the status and condition of the product, and its application. Let's keep brand loyalty out of it, lol.
No deviation from my normal process. These boards have been used before, they are 110 year old white pine barn boards. My website is full of tables and furniture of success. I always lightly plane, keeping some marks, wear, and character. Glue then usually belt sand with 80 then 120 grit.
Soft, aged, porous wood, so it gobbles up the stain. Heavy app with a brush, and by and large it all gets soaked in, nothing really left on the surface to wipe. But admittedly, left and did not wipe.
Day two, second heavy app with brush to darken further. Relative suspicion....coat number one was not "dry" even tho no surface dampness or anything. Waited two days if not three, before varnishing. Looked and felt good to the touch. Not tacky at all or anything.
Varathane oil poly Satin. Always use it, like it. But was an open can, and 20% full only.
Other suspicion....could there be either an excess of, or lack of the "satin" element?
While I always stain with a brush, and often don't wait 3 days...I never have seen this issue. for what it's worth...after looking this am, I can sort of confidently say that there were more than a few of these bleach marks on the legs that now seem to have cured, or evaporated, or whatever...disappeared. And I can pretty much say the top is "less" white or bleached than in the pic...but still way evident. The pic was taken 20-30 min after varnish application.
Anyway....I don't understand it. But have to believe it's related to the humidity level (still very high here) the heavy two coats of stain, the "some sort" of reaction to the varnish. Thanks again....ask anything, I'm not afraid of suggestions of incorrect application or wrong doing. Just don't need to sort through brand battles...trying to solve THIS riddle bettor or worse.
Tim
9/6/15 #19: Varnish dis coloring wood ...
Classic case out not letting the second coat dry long enough. The second heavy coat will take way longer to dry especially if the first coat is not bone dry and the high humidity. The crystalization your seeing is suspended solvents from the 2nd coat in your varnish. It may off gas (as you noticed) completely in time which you may or may not have. I use and would recommend General Finish RTM dye/stains for interior work or their line of exterior stains. They dry fast look way better than minwax and can be used under solvent finishes.
9/6/15 #20: Varnish dis coloring wood ...
I know that Chemmy would have known what caused this. He knew everything.
9/6/15 #21: Varnish dis coloring wood ...
The only "sure" way to figure out what happened is to repeat the process on some wood from the same batch, altering exactly one variable at a time. Prep the wood the same, try a fresh can of Minwax, topcoat with the same varnish. If that doesn't correct it, try a different can of varnish next time.
Repeat until cause becomes clear. If nothing works, it's probably something in the wood. For all you know, someone could have spilled a gallon of motor oil on it 5 years ago...
9/6/15 #22: Varnish dis coloring wood ...
you dont have a pic with stain only by any chance ?
well , its obvious the stain was "removed" during the varnish application......physical contact/manipulation via brush . but there is no "smear" marks in the clear coat ( that i can see anyway) , which is what I would expect to see if the stain was softened by the solvents in the varnish/poly . the stain couldnt just disappear....it would soften and then bleed into the varnish and get brushed out with the varnish . pretty sure that would be visible . does top coat look normal / clear ?
Im starting to lean toward chemical reaction .......varnish vs. contaminant . 100 years is a lot of opportunity .
why didnt the oil stain react or behave differently when applied over the contaminant ?
calling bill nye the science guy.....
sand it off , re-stain with all new product . I would advise to always wipe excess pigment stain . always...always....always . heres why.....if you were to ever call a tech line after experiencing an adhesion failure , the voice on the line will ask about your staining procedure . if you fess up that you dont wipe the excess stain , I guarantee the techs response will be " thats the problem.....sorry , your fault "
9/7/15 #23: Varnish dis coloring wood ...
Tim,
As you know from experience, Minwax stain works well, and it's properties are essential to your hand applied finish schedule. The key to it's success in this application is the drying oil that's used to bind the colorants (dye and pigments) to the wood. Once the oil component in the stain has a chance to cure, it will not lift or smear when the clear coat finish is brushed on. You intuitively know what the problem is - the humidity is high and you applied 2 heavy coats of stain a day or two apart, followed by a hand-applied oil-base varnish.
Drying oils (e.g., linseed oil) cure slowly; once exposed to the air, they absorb oxygen and begin to cross-link and turn into a solid (polymerize). The factors that affect the speed of the cure include how thick the oil is applied and whether the coated item is stored in a warm, dry space with exposure to sunlight while curing. If it's applied thick, the temperature is low, the humidity is high, or it's stored in the dark, the oil will cure more slowly.
By applying two heavy coats of oil-base stain a day or two apart, you increase the cure time significantly (though the depth of color is greatly improved). Under the best conditions the second coat of stain should be given 2-3 days to cure enough to topcoat. But with the humidity high, it can take as long as a few weeks. The stain will not necessarily feel tacky, but it will feel slightly oily and still have an odor. Once thoroughly cured, the stain will feel bone dry and have almost no odor.
It seems obvious that the stain was not properly cured and was easily damaged by the solvents in the varnish when you brushed it on. The areas where the stain was cured a little more still have color.
When you strip the table and start over, you'll see a similar streaking effect as the finish and stain come off. The stain probably has not completely cured and should be pretty easy to remove. Once oil based stains cure completely, you have to scrub them off using stripper and scotchbrite.
9/8/15 #24: Varnish dis coloring wood ...
Tim,
You mentioned that you applied the stain heavily and I agree with some other posts that this could be where the problem is. Sounds like you want a more opaque finish? Minwax type stains are both pigmented and dye based. If you let the solids settle, what remains is something like a dye stain. Having said that, here's a suggestion - apply a straight dye stain to get the background color you want. You can adjust this by adding another dye afterwards. Seal this and then apply a glazing stain that will bring it to a more opaque finish. Seal this and finish with your choice of topcoat.
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