# Thinning urethane/oil (danish oil) & polyurethane mixture



## JerryLH (Oct 23, 2014)

Good day all. Once 'again' I'm in the need of your knowledge (thanks). The title is part of my question but my main question is how thin can one thin a given finish (lacquers, urethane, oil, polyurethanes)? I know - large question - large with a capital 'L'. Via my illiteracy - I have mixed Watco Danish Oil with a polyurethane, applied it - it looks good - but, so does my car when I spray it down with water. Since I have already mixed this concoction - 1. will it adhere (long term) 2. how thin could this concoction be thinned with mineral spirits (if # 1. works)?
Question 3. how thin can one thin the following and still work as an effective finish?
a. Lacquer - 25% - 50% - 75/100%
b. polyurethane 
c. shellac
d. oil/urethane
e. oil

Thanks & Regards - jerry


----------



## bondogaposis (Dec 18, 2011)

You reach a point of diminishing return by thinning too much. The solvent evaporates and when it does you are left with very little finish. The only way to compensate is add more coats. So if you take some standard finish and it takes 4 coats to get the look you want, if you thin it 50/50 it will take 8 coats to get the same final finish. If you thin it 25/75 it will take 16 coats and so on, life is too short. I never thin more than 50:50.


----------



## punkin611 (Feb 24, 2016)

bondogaposis is right on about the effects of thinning finish as long as you use the appropriate thinner. I would not use Danish oil as a thinner on poly as it is just as thick as poly. The best tip I EVER had about oil poly was from a old salt that worked as a painter in a drydock. I saw him slapping on oil poly from a old bucket that was crusty from dried varnish it look as good as I have ever seen. He winked and told me the secret; he said you got to thin the varnish-- 50/50 with mineral spirits


----------



## JerryLH (Oct 23, 2014)

Thanks for the feedback - 50/50 is the rule of thumb info I was looking for. Thanks again. 
I do have another question. It seems no matter what lengths I go to, to remove dust from my work area, I still get dust nibs in my finish. It seems no matter how fine I go with my wet/dry sandpaper (I've gone up to 2400) in removing the nibs - I can see the haze created by my attempts to remove the nibs (without creating the haze)? OK - that's it for-the moment.

Regards, Jerry


----------



## wapakfred (Jul 29, 2011)

Dust nibs seem to be a fact of life, you would probably need a NASA "clean room" to completely escape them. Two suggestions for you to try: the first and easiest is to wait until the finish is fairly hard (several days at least) and rub it with kraft paper wadded up into a ball (that's the old brown grocery bag trick). This works really well, but if the finish is soft can leave striations. The second is to do as you are (stop around 1000 grit, and them apply a coat of wiping varnish, this the varnish thinned 50/50 with MS that punkin mentioned. This should tack up quickly enough that the dust won't have a chance to affect…though there may still be a few spots. All this is improved greatly if you have an ambient air cleaner that you runn a few hours before finishing. That can be a homemade one using a recycled furnace fan with some tight filtration filters (think Filtrete Ultra-a allergen) in it.


----------



## JerryLH (Oct 23, 2014)

Thank you so much for your feedback - I greatly appreciate those who are willing to share what they've learned with others.

Regards, Jerry


----------



## Rick Dennington (Aug 27, 2009)

What I usually do on a fine piece of furniture is I put 2 coats of clear Danish oil on, let it dry good for 2-3 days between coats (after the final sanding), then put 4-5 coats of poly over the oil, (not thinned), and lightly sanding in between coats….When I do the in-between coats, I turn on my air cleaner to scrub the air of fine particles hanging in the air, so they won't settle on the project while it dries…..About the only finish I thin is tung oil w/a 4:1 ratio….One part oil to 4 parts of mineral spirits…..Sometimes a 50/50 mix, but not often…..On some projects that thins it too much, and you have to use more coats…On the final finishes, I run the air cleaner about 2+ hours to "clear the air"....


----------



## JerryLH (Oct 23, 2014)

> What I usually do on a fine piece of furniture is I put 2 coats of clear Danish oil on, let it dry good for 2-3 days between coats (after the final sanding), then put 4-5 coats of poly over the oil, (not thinned), and lightly sanding in between coats….When I do the in-between coats, I turn on my air cleaner to scrub the air of fine particles hanging in the air, so they won t settle on the project while it dries…..About the only finish I thin is tung oil w/a 4:1 ratio….One part oil to 4 parts of mineral spirits…..Sometimes a 50/50 mix, but not often…..On some projects that thins it too much, and you have to use more coats…On the final finishes, I run the air cleaner about 2+ hours to "clear the air"....
> 
> - Rick Dennington


Thank You Rick.


----------



## ArtMann (Mar 1, 2016)

Watco Danish Oil already contains polyurethane varnish. Why mix?


----------



## JerryLH (Oct 23, 2014)

I had a part of a can of General oil/urethane satin - I had a can of high gloss polyurethane. I wanted something in between.

Regards, Jerry


----------



## punkin611 (Feb 24, 2016)

I wanted to add; use gloss varnish, satin has a flatting agent in it that gives uneven results. With gloss you can made it satin with 0000 steel wool, it as takes care of the dust nibs. Also buy varnish in 1/2 pints because it does not keep good for a long time.


----------



## JerryLH (Oct 23, 2014)

> I wanted to add; use gloss varnish, satin has a flatting agent in it that gives uneven results. With gloss you can made it satin with 0000 steel wool, it as takes care of the dust nibs. Also buy varnish in 1/2 pints because it does not keep good for a long time.
> 
> - punkin611


Thanks again for the feedback. Lumberjock's (members) are a great resource.

Regards, Jerry


----------

