Help! 7 coats of poly and still streaks!

[Nlafer]

I am looking for some help.

I have just put on 7 coats of Minwax water-based Oil Modified polyurethane on my table. For reference, the table is wormy maple and was sanded to a very smooth finish. I expected the first few coats to be uneven as the wood absorbed the poly, however I still see major streak marks in the poly and I am now 7 coats in. I have been sanding with a high grit paper in between coats. I have also been cleaning all the dust before applying the next coat of poly. The problem I am having is that the poly is too thick and leaves all the marks from the brush or foam ( I have tried both. )

I have read various posts and wonder if I could try sanding again and applying some thinned out poly? Should I thin with water? Any other recommendations?

 

Hopefully you can see in the pics attached.

Thanks in advance!

PS. I'm doing this in my dining room, and I don't have alot of tools (cannot spray).

 

[wtnhighlander]

If by 'streaks' you mean brush marks, my understanding is that happens when the finish dries before the marks have time to level out. Some of the more expert finishing guys may have better advice, but my limited experience says that you may be brushing it on too thin. A heavier coat dries more slowly and has time to self-level. That works with oil-based, not sure about water based.

[Nlafer]

Thanks so much for that info. Do you think a heavier coat will fill in the existing marks that now seem to be 3-4 layers down, or do you think I need to take off all the finish? 

[Tpt life]

Poly can be overworked. Work it as little as possible. 

[Nlafer]

 

 

I'm probably being silly here, but can you explain in more detail? I'm trying to just put one coat and not go over it too much.. do you think there's a way to repair the 7 coats of brush streaks? 

[Larry Moore]

You need to sand it back to a matte look then lay down a new coat. I don't know about your product but I have never had good luck brushing water based finish. 

[thatCharlieDude]

You may want to try applying with a rag

[Nlafer]

Hi Larry, what would you suggest to apply it? A rag? I read that it just gets messy and gummy with water based. Could I put on wipe on oil poly on top of this? 

[Coop]

http://www.minwax.com/wood-products/clear-protective-finishes/interior/minwax-water-based-oilmodified-polyurethane#directions

says to apply a THIN Coat with a brush but does not mention thinning. It looks like you have some serious deep stroke marks there. So a serious sanding may be required to get you back down to smooth. It also says that it dries quickly so as mentioned above, don’t over work it ( multiple strokes over the same area). 

[Jfitz]

Applying another coat will never get rid of streaks or brush marks from a previous coat.  If you have brush marks you need to sand it to a uniform sheen/appearance, and then continue with another coat.  As mentioned above, poly can do this when "worked too much" - i.e. going back over it after it has started to set.  on a flat surface, poly should pretty much self-level.  Thinning the poly can help it flow, but you don't think with water - mineral spirits being the normal solvent with which to thin, but for final coats when you want it to dry quickly (to avoid any settling dust from sticking while it dries) some people use naptha.  please be careful with the fumes if finishing indoors - a window fan blowing out, with an open window on the opposite side of the room, can create a nice cross ventilation.

If I were you...I'd sand the whole surface down to a uniform sheen (i.e. no more streaks showing),; vacuum up the dust;  then apply a thinned poly (thinned 50% with mineral spirits).  Personally I don't like brushes for poly ; I use a cotton rag (old t-shirts work well since they have little to no lint) cut into a long strip and folded in half, then in half, then in half...you get the idea.  it makes a nice pad.  Nice long strokes end to end, and then move over a little, slightly overlapping.  Once you've applied some and it starts to dry, LEAVE IT ALONE.  Going back over it will just cause issues.

 

[Nlafer]

3 minutes ago, Jfitz said:

Applying another coat will never get rid of streaks or brush marks from a previous coat.  If you have brush marks you need to sand it to a uniform sheen/appearance, and then continue with another coat.  As mentioned above, poly can do this when "worked too much" - i.e. going back over it after it has started to set.  on a flat surface, poly should pretty much self-level.  Thinning the poly can help it flow, but you don't think with water - mineral spirits being the normal solvent with which to thin, but for final coats when you want it to dry quickly (to avoid any settling dust from sticking while it dries) some people use naptha.  please be careful with the fumes if finishing indoors - a window fan blowing out, with an open window on the opposite side of the room, can create a nice cross ventilation.

If I were you...I'd sand the whole surface down to a uniform sheen (i.e. no more streaks showing),; vacuum up the dust;  then apply a thinned poly (thinned 50% with mineral spirits).  Personally I don't like brushes for poly ; I use a cotton rag (old t-shirts work well since they have little to no lint) cut into a long strip and folded in half, then in half, then in half...you get the idea.  it makes a nice pad.  Nice long strokes end to end, and then move over a little, slightly overlapping.  Once you've applied some and it starts to dry, LEAVE IT ALONE.  Going back over it will just cause issues.

 

Awesome. Thanks for the info. Can you thin water based poly with mineral spirits?

[Jfitz]

6 minutes ago, Nlafer said:

Awesome. Thanks for the info. Can you thin water based poly with mineral spirits?

I believe you thin water based poly with water, but you can't as much (50%)....but I'll defer to others who have used WB poly.

 

[wdwerker]

Lots of sanding, thoroughly cleaning and then a wet coat with very light pressure on the brush. Your not trying to flood it on and your not trying to spread it thin either. Don't use a cheap coarse bristled brush either.  Dip the brush only slightly, do not wipe on the rim. 

[Unknown craftsman]

Maybe you should wait till spring. So you can do a proper finish on your table outside. I can't imagine it's a good thing breathing the finish as it dries. I also agree with other start over - scrape off you work and sand back to wood.

Aj

[Jim DaddyO]

You can thin water based poly with Floe trol.  You have to keep mixing it though as it will separate.  

When the expression "don't work it too much" comes up, that means while applying it.  Don't go back and forth repeatedly, use as few strokes as possible applying it and don't go back over it.

Looks like you have some sanding to do first to get rid of the brush marks you already have as has been mentioned.  Sand to a uniform dull finish.  If you see glossy spots, that is where you missed.

This is how I ended up doing my coffee table.....The first 8 or 9 minutes is the finishing of the top.  High gloss water based poly.

 

[Larry Moore]

6 hours ago, Nlafer said:

Hi Larry, what would you suggest to apply it? A rag? I read that it just gets messy and gummy with water based. Could I put on wipe on oil poly on top of this? 

I haven't used a brush to apply finish in a long time. Water based I spray, but I generally use Arm R Seal and wipe it on. I don't know how an oil based poly would work over a water based product.

[wdwerker]

Usually water based can go over " cured " oil base but oil over a waterbase can have issues. 

[Minnesota Steve]

That was my experience with water based poly as well.   I think it just has to be sprayed.

 

[wdwerker]

There are a lot better waterbourne finishes than Minwax. I spray 99.5 % of the time but occasionally it's not worth setting up to spray  1 panel. I use a foam brush very gently. Slight dip in the finish, no wipe on lip, an extremely light stroke to spread it, maybe one extra pass to spread it better but no multiple strokes. Then I gently wipe the brush w a damp paper towel to remove any bubbles before I dip again. I do not spread it very thin but I don't leave puddles. When that coat is completely dry I sand between coats with 220 or 320 and a cork block to flatten any brush marks and those little bumps that can form from dust landing on a wet finish.

I would use 150 or 180 on a random orbit sander to completely flatten what you have so far. Then 220, then 320 before adding any more finish.

[Chestnut]

I get that there are a lot better finishes than minwax. I don't disagree but why is it that they have so much market share with them being so awful? Price really isn't that different. I wish that general would get over their authorized dealer BS cause they could steal a lot of market share if they sold their products in the box stores. Most of the reason i don't use their products it's because they are so dang difficult to get my hands on.

[wdwerker]

Our local Woodcraft carries General Finishes.  So does Our Rockler store.

[Jfitz]

Also pretty lucky here - local Woodcraft carries GF, but Minwax can be bought anywhere. 

I don't know if I'd call Minwax 'awful'.  In fact, I recall their wiping poly got pretty good marks in one of the magazines' comparison tests.  Marc did a comparison too, (https://www.thewoodwhisperer.com/videos/wiping-varnish-shootout/) and Minwax did pretty well - the complaint/observation about it looking too much like plastic seemed to be more about the gloss finish.  I usually use semi gloss or satin, and to be honest I've been very happy with the results.

 

[Chestnut]

Never had those in ND and they are still a long drive for me here. It's just too easy to grab something on the way home form work and never have to make a special trip.

[AceHoleInOne]

You need to sand it back smooth.

I think it's setting up on you too fast since your working a large area. General Finishes has a similar (umm, I mean a better product )  called Enduro-Var, that can be applied with a roller, along with other methods. 

I wonder if you can find out from minwax if that product can be applied with a roller? It would definitely help you apply the product faster so it can flow out before it starts to set-up.

 

-Ace- 

[wdwerker]

Didn't think of that approach. I think a lambswool applicator like they use for floors is another possibility.  I would wash a new one in the sink and rinse several times to get rid of any loose fibers. 

A lot of the problems with Minwax stains are people trying to duplicate dark rich finishes like they see on factory furniture and cabinets. Then they get in to big of a hurry to put the finish over it. Plus the resins in Minwax stain doesn't play well with modern finishes. Minwax hasn't changed for the worse, they just haven't kept up with the times. So much better stuff out there.  Finishing is part chemistry and part art. Read, learn and practice before you jump in the deep end !