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Lasse Hilbrandt
03-15-2016, 11:15 AM
Sometimes its difficult to figure out what all the different kind of finishes is in my language (danish)
Untill today I thought that wipe on poly was polyuretan varnish that was supposed to be wiped on instead of using a brush. But today I spoke to a professional paint store owner and she says that polyuretan can't be wiped on so I guess wipe on poly isn't what I thought it was ?

Barry McFadden
03-15-2016, 11:46 AM
Wipe on Poly is supposed to be wiped on with a cloth or cheesecloth. I have used it for all my turnings for the last couple of years ever since I heard of it. The paint store owner is wrong. Here is an example of the product... https://www.homedepot.ca/en/home/p.wipe-on-poly---satin.1000421875.html

Lasse Hilbrandt
03-15-2016, 11:59 AM
So it consist of a varnish blend and a hardener. ?

Al Launier
03-15-2016, 12:12 PM
This is a question that I'm also interested in. I thought that Wipe on Poly was diluted somewhat with something for easier penetration into the wood grain, but I'm guessing at that. So, if its just regular Pollurethane why is it advertised as Wipe On?

Barry McFadden
03-15-2016, 12:29 PM
So it consist of a varnish blend and a hardener. ?

I don't know the physical properties of it but I know it dries quickly and is a very hard finish. I don't use anything else..

Jon Nuckles
03-15-2016, 12:40 PM
I have read many places, and I think Bob Flexner's book was one of them, that wipe on poly is just polyurethane that has been thinned enough to allow it to be wiped on. Many people suggest making your own using brush on poly and mineral spirits to save money.

Prashun Patel
03-15-2016, 1:06 PM
Lasse, reading your dialog I see you might have misunderstood.

Poly is usually too thick out of the can to wipe and it must be brushed.

If you thin it with minera spirits yourself you create a wiping varnish. Or you can buy prethinned poly that is sold as wiping varnish.

It is the same resin in both products. Just diluted.

Lasse Hilbrandt
03-15-2016, 1:19 PM
I thought that "poly" meant that it consisted of two components that were to be mixed ?

John Sanford
03-15-2016, 2:10 PM
I thought that "poly" meant that it consisted of two components that were to be mixed ?

Not in this case. It specifically refers to the "polyurethane" resins in the varnish, as opposed to alkyd resins, phenolic resins, etc. A "wiping varnish" is simply a varnish that has been thinned enough to allow practical application by wiping as opposed to requiring brushing. Thinning it thus will generally result in faster curing, but also each coat will be thinner than the equivalent varnish unthinned and applied with a brush.

Lasse Hilbrandt
03-15-2016, 3:07 PM
Ok, thanks. Good info.

Howard Acheson
03-18-2016, 3:12 PM
>>>> I spoke to a professional paint store owner and she says that polyuretan can't be wiped on so I guess wipe on poly isn't what I thought it was

Thinned oil based poly varnish certainly can be wiped on. It's been done for years. Following is some info about the process.

Here is something that should help. A friend of mine who was an early advocate, put it together years ago and it has worked well for many.

QUOTE

There are a number of suggested application regimens that are totally subjective. The number of coats in a given day, the % of cut on various coats, which coat to sand after, when to use the blade and a whole host of other practices are all minor differences between finishers. There are some things that I consider sacred when applying a wipe-on finish.

First, you can use any full strength oil based clear or non-gloss finish. The gloss of the final coat of finish will determine the final gloss of the finish. Polyurethane varnish or non-poly varnish is fine.

If you are making your own wipe-on the mix is scientific - thin. I suggest 50/50 with mineral spirits because it is easier to type than any other ratio and easy to remember. Some finish formulators have jumped on the bandwagon and you can now get "wipe on" finish pre-mixed. If you use a pre-mixed, thinning is generally not necessary. But making your own is cheaper and you know what's in it.

The number of coats in a given day is not important. Important is to apply a wet coat with an applicator and merely get it on. Think of a 16 year old kid working as a busboy at Denny's you have sent over to wipe off a table. Sort of rub/swirl the the material on like you would if you were applying a paste wax. Don't attempt any straight strokes. The applicator should be wet but not soaked. The applicator can be a non-embossed paper towel shop towel, half a T-shirt sleeve or that one sock left after a load of washing. Once applied,leave it alone. The surface should not be glossy or wet looking and, if applied correctly, there should be no "brush stroke" type marks. If you have missed a spot, ignore it - you will get it on the next coat. If you try and fix a missed spot you will leave a mark in the finish.

Timing for a second coat involves the pinkie test. Touch the surface with your pinkie. If nothing comes off you are ready for another coat. If was tacky 5 minutes ago but not now, apply your next coat just as you applied the previous coat. Remember, you are wet wiping, not flooding. After applying the second coat, let it fully dry for 48 hours. Using 320 paper and a sanding block lightly sand the surface flat. Now, begin applying more coats. Do not sand between coats unless you have allowed more than 24 hours to elapse since the prior coat. The number of coats is not critical - there is no critical or right number to apply. For those who need a rule, four more coats on non-critical surfaces or six more coats on surfaces that will get abraded seems to work.

After your last coat has dried at least over night you will have boogers in the surface. You should not have marks in the surface because you ignored application flaws. You may have dust, lint and, if you live in Texas, bug legs. Use a utility knife blade at this point. Hold it between your thumb and forefinger, near the vertical, and gently scrape the surface. Gentle is the important word - no harder than you would scrape your face. If you start scraping aggressively you will leave small cut marks in the surface. After you have scraped to the baby butt stage gently abrade the surface with 320 dry paper or a gray ScotchBrite. Clean off the surface. Now, leave the area for two hours and change your clothes. Apply your last coat with a bit more care than the previous coats and walk away.

An anal person is going to have a tough time with this process. Missed spots have to be ignored. Wet wipe, don't flood. Scraping to babies butt smooth means scraping no harder than scraping a babies butt. Ignoring any of these will leave marks that are tough to get out. Getting these marks out requires some aggressive sanding to flatten out the surface and starting over.

Jim Kull

END QUOTE

Lasse Hilbrandt
03-18-2016, 5:14 PM
Thanks Howie. Very informative.

Unfortunately what I have is waterbased acryllic/poly ureathane varnish. I think I will try the "burn" method. Im just wondering when one can apply the next layer ?

Robert long Ohio
03-19-2016, 11:39 PM
I don't know the physical properties of it but I know it dries quickly and is a very hard finish. I don't use anything else..
I always use the brush on poly method. I am going to attempt the wipe on method on a closet shelf unit I built. I have never tried wipe on. I guess no better place to try it then something that will be permanently in a closet and out of sight. I'm going with a 50/50 mix. I hope I get the same results but not nearly time consuming