[p2sue]

I've installed knotty alder doors and trim in my house and I used Minwax satin wipe-on polyurethane. I've had bad luck with white cloudiness in some spots. I'm thinking it's a moisture problem (bathroom, mopped floor areas).

I've stripped it off and tried a different product and ensured it was mixed thoroughly (since I read that mixing might be a problem with satin finishes) and still have the cloudiness issues.

Does anyone having any recommendations? Should I try a different type of finish?

 

[1acre]

seems to be following the grain somewhat? it's hard to see in the picture what is going on.

how many coats have you applied? are you wiping or brushing? have you thinned the varnish at all?

 

[p2sue]

I only wiped on one coat and did not thin it at all.

 

[ZZZZZ]

Is it a water-based or oil-based stain you are trying to put poly over?

The Minwax poly can be either oil or water-based, check the label. Sometimes oil and water don't mix.

 

[p2sue]

Good catch. I didn't even think about that.

It was stained with Minwax oil based natural stain. I didn't see any details on the Minwax wipe-on poly but the second type of poly (pictured) says it is oil. The Minwax was stripped off before the new poly was used but I wonder if I didn't get it all.

Another quick question...is there a need for natural stain under poly? I always remember doing it in woodshop growing up but I never understood the need since the poly should protect the wood, right?

 

[1acre]

No need for stain under poly. Water or oil based doesn't matter. You most likely just need more coats of your finish. Do you have some scrap you can test on? Even a piece of pine should mimic what is happening on your alder. Wipe on poly is just a thinned version usually. This all based on poor pictures of the problem. Post a closer up image of what is happening and perhaps we can zero in on it better. But my best guess is you are wiping on very thin coats which are being absorbed into the wood grain differently and you haven't started to build your film yet. You're probably also wiping on very inconsistently on the vertical surface. I like to keep a nice puddle in front of my brush for finishes, one pass and then move on. Very difficult on a hung door.

 

[joecaption]

Also a wipe on polys not going to give you nearly enough coverage to protect the wood long term.

 

[p2sue]

Thanks for the tips. I'm about to try again. I just wanted to get everyone's thoughts before I do it a third time just to receive the same result.

I guess this time I'll use quite a few coats and hopefully that will help. I also have a wood conditioner that I could apply first. Does anyone think that would help or is that mostly just for helping with darker stains?

If I strip/sand the troubled area and re-apply the poly, do you think I'll have any issues at the overlapping areas (old poly w/ new)?

Thanks again for all of the advice.

 

[1acre]

re: wood conditioner - if I were a betting man, I would guess the "wood conditioner" is nothing more than thinned down varnish. Same thing I said about your wipe on poly. It's important to note, polyurethane is a type of varnish. In other words, you're wasting money on "wood conditioner." My guess is the wipe on poly is very similar to the wood conditioner, perhaps just a different resin. These companies don't tell us what is actually in their products and many people fall for it. Myself included until I got educated. Guru Flexner will show you the way if you check his book out from your local library. An article from him for reference....

http://www.popularwoodworking.com/techniques/finishing/the_basics_of_wiping_varnish2

I believe applying a stripper is a waste of time (and money) in this instance. You really should be using a methylene chloride w/ ammonium hydroxide stripper, which is very noxious. Also, varnishes are pretty much plug and play in terms of coat to coat assuming you allow for adequate cure time. I'd scuff the surface with a pad or high grit sand paper, vacuum, tack cloth and then go to the next coat.

Again, I would use a test piece or inconspicuous test area first. I still believe your finish is being absorbed into the wood grain differently (happens all the time) and you haven't started to build your finish. I also haven't seen a close image either. Good luck. Poly is a bear to work with in my opinion.

 

[p2sue]

Sounds good. Thanks.