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Streaking Poly Topcoat on Curly Maple

4K views 11 replies 6 participants last post by  livelite 
#1 · (Edited by Moderator)
I'm having issues with applying a wipe on poly topcoat on a curly maple table. Streaking occurs every time after the second or third coat. So far, the GF wipe on had the least problems, but the can was quite old.

So, I tried some danish oil that was lying around and absolutely love the finish. But the topcoat of poly streaked again. I've made about six to seven attempts with no avail. I considering using other oils that out there, waterlox, BLO, tung oil, etc. but concerned of the protection issue. I'm shooting for the natural grain "pop" with a rubbed out look with a durable and smooth finish, but not necessarily a high gloss appearance.

I know this is an old topic, but it is still a topic.

Any suggestions?
 
#2 ·
Elaborate on "streaking". Also what type of poly are you using? Wipe on poly, full strength, waterborne or oil based? How are you applying it - spray, wipe on, brush?

Also, every other product you mentioned is essentially the same thing. Danish oil, Waterlox and tung oil are oil/varnish blends. They offer about the same amount of protection (very little). BLO offers almost no protection at all.
 
#3 · (Edited by Moderator)
Coats after the first will combine with it and polymerize faster than the first, and that causes the streaking. The fix is to slow down the chemical process, and one way is to add a little pure tung oil to the poly mix for second and subsequent coats.
 
#4 ·
It's possible that you are just wiping too hard.

The first couple of coats will start to build a hard, smooth surface. After that, you have to wipe the finish on very gently, making sure the surface is evenly wet with fresh poly. If you apply too much pressure in spots, you will literally be wiping the finish off at the same time you are trying to wipe it on.
 
#6 ·
I'd like to see a photo of the streaks, as they could have different causes depending on what they look like.

If varnishes cure past a certain point, the next coat lays on top of the previous, it doesn't burn in. This causes white or yellowish "witness lines" when rubbed out or sanded, as you cut through discrete layers.
 
#7 ·
The table originally had GF arm-r-seal applied by wipe on/wipe off. Yep. wipe off. Charles Neil personally advised me to do so. And a great finish it was. No need to buff or scuff sand in between coats. The problem was I didn't apply enough to take the abuse of the table top. My bad.

Now, streaking is occurring. They run length ways with the grain. I've used minwax wipe on poly, gloss, and even tired GF satin using a t-shirt. In talking with Minwax and Sherwin Williams customer support, which both are excellent, they both agree that the air vent above the table can be drying the poly faster than normal not allowing for a quick tipping off of the finish. The table is 2' by 4' so there should be enough time to do so. Also, the GF satin can was not a new can, and that could have also caused problems. I'm wiping the poly like one would waxing a car not just with the grain. The first coat goes on sweet with little problems with both the minwax as well as the arm-r-seal. But that second coat the poly seems to go kinda "sticky" and not allowing me to level off the finish. Hmm, weird.

Anyway, I'm thinking about going back to the original formula of a shellac wash coat and if possible arm-r-seal again. Since the Woodcraft store closed in my area, :( I would have to order the can online or perhaps make up my own. This time the air will be shut off. I never had this problem before and inclined to think it's the a/c vent issue.

Any feedback would be appreciated.
 
#9 ·
Your last post prompted me to go look up the directions for Minwax wipe-on poly. I've used it on dozens of projects, and all of them wrong I guess. They say to "rub into the wood" even on successive coats. To me, "rubbing something in" implies that you must have a porous enough surface to absorb what you are rubbing in.

The stickiness you are feeling is exactly what I would expect from trying to rub the finish into an already-sealed surface. As you wipe, the majority is coming right back off, and what little that's left on the surface is drying almost immediately, causing the friction you feel. The streaking, in turn, suggests to me that the most recent coat has not fully covered.

Again, this is just based on my personal experience with a product I have used quite a bit. I can't speak for the GF finishes, as I have next to no experience there.
 
#10 ·
Yes I'm sanding back the finish back to the barewood with every try. Thus, this project is becoming an Achilles heel. Meanwhile, I refinished a birch writing table with mw wipe on and an oak coffee table with the same. No problems. I'm leaning towards what CharlieM1958 mentioned. Perhaps the coats are not dry enough or it is not being fully covered; the lighting isn't the best. Although they seem dry to touch, maybe more additional time between coats is needed. Also in my limited experience, preparing the surface could also be the problem. I am trying out a small test piece to see what is going on, instead on attempting another try. So far, the mw poly isn't drying as quickly as I thought it would. Hmmm. The surface is probably sealed enough so the poly is just not adhering properly. I may have to settle on one coat of the poly over the shellac and leave it at that, to save my sanity. The minwax customer service rep said that two coats of the wipe on is all I needed. Really? My ears were cleaned out after that statement. I thought and read 3 to 4 coats were needed for a table top. If two is all that is needed, cool beans. Meanwhile i sanded back the finish with 120 and 220 grit and it is almost ready for another try.
 
#11 ·
I would highly recommend reading Bob Flexners book "Flexner on finishing". There is tons of good info there. To give you the TL;DR version:

1 - A wiping varnish is a wiping varnish
2 - Pretty much everything on the can, including the instructions is BS
3 - Wiping varnish is nothing but thinned varnish (in this case, MW ploy with mineral spirits)

What I would do is sand it down smooth and throw down a seal coat of dewaxed shellac. SUPER IMPORTANT that it is dewaxed. This is usually sold as "seal coat". If you can't get dewaxed, get the waxed stuff and decant it.

Apply the shellac, let it cure for several hours or overnight. Gently sand it down with 400 grit stearated sandpaper. Get all the dust off and apply the wiping varnish. Apply generously with a rag. Give it a few minutes and then wipe the excess WITH the grain. Don't over wipe. Just get the excess off. Let it cure over night then sand and do it over. If this is a kitchen table so I would do a minimum 4 or 5 coats of wiping varnish.
Let that cure completely - 7 to 10 days or until it doesn't smell like poly anymore. If you want to wax it, go ahead (don't use a silicone based wax like automotive stuff, use furniture paste wax). If not, buff it with a brown paper bag. Seriously. It works great at getting the little dust nibs out.
 
#12 ·
Interesting. I tried to use a washcoat again and I didn't like it. With the large surface area, there wasn't ample coverage with dry spots I missed. The danish oil had a better appearance so that went back on. This time I mixed a pill bottle full of the Minwax W.P. into about a quarter filled can of the danish oil. Not much, since I didn't do any testing as well as the overall integrity of the finish might be in question, since the w.p. has thinners in it as well as the danish oil. Anyways, the finish look great. Smooth as glass l and it's only been less than 24 hours. I don't know if a fine film of shellac was still present even with sanding it down with 120 through 320. Or The added w.p. poly made the difference. The surface is dry to touch and I will let it dry another day before doing anything else to it. Before, the danish oil still had some dull spots and was still drying. the pic isn't that good for I used a cell phone to take it.
Wood Rectangle Flooring Composite material Tints and shades

Next I'm considering using the wp for added protection. Or perhaps another coat.
 

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