Blocking: Eliminate by Polyurethane Finish?

[wendi]

Can you eliminate or at least minimize the problem of blocking by apply a polyurethane finish (or varnish) on top of your paint job?

Thx in advance.

[Bonehenge]

Shellac

Barry

[Joseph Meehan]

Yes and know. Applying any new finish that does not block as badly will take care of it. Different types of finishes and different brands and product lines have different blocking characteristics. Next time make sure you get a finish that has the right properties for the intended use.

[m Ransley]

Blocking ,do you mean stains ? If it is for kitchen cabinets reprime with the right primer. after it cures . But Latex on kitchen cabinets is not a great idea , it is absorbetave and more reactive to hand oils. It will not last as long. Ben Moore Enamel Underbody , sand 220g and Ben Moore Satin Impervo with Penetrol. or spray can it. Let it cure out though.

[wendi]

Blocking as it when two painted surfaces sticking together. In my case, it would be the cabinet door or drawer sticking to the facing. Yeah, I realized that's another drawback of latex, esp if I'm using satin sheen latex. I should at least go with a semi-gloss for better block resistance. I'm considering using lacquer or latex+floetrol. And hopefully, the protective clear topcoat would further reduce the blocking problem.

-wen

[wendi]

It's for kitchen cabinet. I'm afraid Shellac is not very appropriate.

[Bonehenge]

You'd be surprised at what shellac is appropriate for.

Barry

[m Ransley]

Run a dehumidifier in the room I had rich red latex take 6 months to cure in a 70 % humid basement. Shellac may react until the latex is cures fully.

[Baron]

1. Use a high quality paint meant for kitchen use. These are usually denoted by "scrubable" or "washable" in the type.

1. Latex paint typically takes two weeks to fully cure. They dry in about half a day.

2. I'm not so sure applying a transparent topcoat to incompletely cured latex paint is such a good idea.

1. Use a waterborne clearcoat if you want to topcoat. It imparts very little yellow, unlike varnish or polyurethane. The clearcoat will protect the color coat and make any future repairs easier.

Good Luck.

[wendi]

Hi Baron,

Thx for your responses. I've been getting a lot of help from people in this forum. I think I'm finally heading in the right direction. A few people suggested using solvent-based product to get a professional look. Unfortunatley, I just don't have the kind of equipment (explosion tight spray booth, "Mickey Mouse" mask and cleaning system for the spray gun) to do that. I have to stick with waterborne product. And after doing a little of research, I found there're a lot more selection for water-based products nowadays.

I have just finished priming the first coat. I'm now trying to correct some of the priming mistakes (See the "How to Correct Priming Mistakes on Oak?" thread)....

See inline (below) for the rest of the reply....

I'm trying to color match the Ultima Spray Lacquer made by Target

It's a waterbased product => easy clean up :). People seem to think that lacquer is easier to work with (gives smoother finish) than latex/acrylic paint. I'm also hoping that lacquer would eliminate blocking.

Probably not. I was going to let it cure for 1 week. Now that you mentioned it, I should probably do 2 weeks.

Hm... What do you mean by waterborne clearcoat? Both varnish and polyurethane come in waterborne formula too (I thought you mentioned that in another thread also, or do you mean something else?). I found a few promising clearcoat products...

1. "Euduro Wat-R-Based Poly Overprint" got rave reviews by Andy Charron (from FineWoodWorking.com)

1. Homestead praises Fuhr claiming that its Urethane and Acrylic Varnish are the best product out there period.

Fuhr's product line is somewhat confusing. There is Urethane, and Acrylic/Urethane. What are the differences?

-wen

[Bonehenge]

Clear shellac comes in spray cans, is non-toxic, doesn't yellow, breathes, dries extremely fast, and is easily repairable. The dewaxed variety, which is what is in the spray cans, can also be overcoated with just about anything. This is good when you change your mind about the color some day.

If you would try it over your latex on a piece of scrap you'd see that I'm not kidding.

Shellac is a universal barrier and is compatible with just about anything, under or over it. Unfortunately, most trades people outside of high-end woodworkers no longer have a clue about it.

Barry

[m Ransley]

Explosion , spray booth ? You are on the wrong track again.

[nospambob]

[nospambob]

[Baron]

In theory, someone that knows how to spray pigmented lacquer will be able to do it faster than spraying latex paint. This is due to the solvents in lacquer. The smoothness is a function of ability.

A waterborne clearcoat is just that. It could be a varnish, urethane, or a lacquer. As long as it has water in it and is transparent, it fits the definition.

One is a mixture and one isn't. They have different properties.

It sounds to me like you are getting way in over your head and will be spending quite a bit of money. Perhaps learning how to brush paint without leaving brush marks would be the cheapest and easiest solution?

Good Luck.