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Al Willits
04-21-2008, 8:31 AM
Having applied the first coat of watco and not wet sanding (forgot) it like some have suggested, I let it dry for a few days, and thought the finish was a bit rough...so

Not being sure if wet sanding the Watco Danish Natural oil I'm using after the first coat dries does any good, I thought I experiment a bit.

Seems wet sanding the second coat of the watco thinned about 25% with mineral spirits with 400 wet or dry has left a very smooth surface, just wondering if this method makes sense or am I wasting my time with the wet sanding?

I'm planing on using a wipe on poly after all this, if that makes any difference?
tia

Al

Prashun Patel
04-21-2008, 8:55 AM
Makes perfect sense. The first coat can raise grain a little. Wet or dry sanding knocks those fibers down. Some also say that wet sanding with mineral spirits reemulsifies the resins and pushes the slurry into the pores to fill them.

One caveat: make sure you can apply the poly directly over the danish oil.

On my current project, I used shellac (1# cut, 2 coats - sanded, 30 mins drying btn coats) between the d-oil and my top coat (which was alkyd varnish). I found it primes the surface well and helped to achieve a smooth topcoat much quicker on the pieces that I did not apply it on. (I've been told you need dewaxed shellac under poly, though.)

Al Willits
04-21-2008, 9:26 AM
Thanks Shawn, the watco and poly are all I'm planning on using, if that's what you mean?
The only question I have now is after I wet sand and let dry, should I do anything to the surface before I apply the poly?

Al

Prashun Patel
04-21-2008, 10:04 AM
Just let the d-oil dry thoroughly.

Howard Acheson
04-21-2008, 12:59 PM
Al, let's step back and look at what you are doing.

First, if you are planing to clear coat with varnish or poly varnish, it makes no sense to first use something like Watco Danish Oil initially. The Watco is almost completely linseed oil and it's the linseed oil that colors the wood or "pops" the grain. If that coloring or grain enhancement is what you want, just apply a heavy coat of BLO, let it set for 15-30 minutes and wipe it dry and then let it fully dry overnight. Then you can apply your varnish or poly varnish top coats. Apply the first coat thinned about 25-30% with mineral spirits. Let it dry a day or two and flat sand it with 320 paper on a sanding block. This is where you work on the smoothness. Once smooth and flat, apply 2-3 more coats thinned 10% and you're done.

Even it you were using the Watco, there is no need for more than one coat. And, you do not need to be particularly concerned with its smoothness. Super smoothness will NOT translate into your top coat being any smoother. As above, it's after the first coat of you final finish that smoothness counts.

Another point, oil/varnish finishes like Watco, Minwax Tung Oil Finish and others are intended to be complete finishing systems. They are not intended to be overcoated with a film finish. They are designed to be in-the-wood finishes that leave the look and feel of the wood. An application technique is to apply the initial coat, wipe it off and let it fully dry. Then apply a second application and sanding it in using 320 or 400 Wet&Dry paper. But, the bottom line is that it's a waste of time and money to use one of those finishes and then overcoat it with something else.

Al Willits
04-21-2008, 2:50 PM
Thanks all.
Howard, I used watco because on the wood we tried it on it darkened the wood less than BLO, could have been brands, age of materials or ? but the blo made it slightly darker.

Second coat of watco wouldn't have been necessary if I'd remembered to wet sand the first coat, we differ in finishing methods as I think all coats should be smooth, prob my auto body experience, but I feel better not depending on final coat, different strokes I guess.

Also many have suggested the poly over the watco as a good finish for a TV cabinet, and I like the finish so were back to different strokes again.. :)
Appreciate the comments though.

Al

Al Willits
04-23-2008, 5:27 PM
ok, little update.. seems as the second coat wet sanded with a thinned mixture of Watco Dainish natural oil has made a very nice smooth surface, whether that could have been done with only one coat is unknown to me, but I suspect it would work.
Now this part is done I'll wait for it to dry and apply the poly for protection.
The finish is very nice in my newbie mind, and the wife loves it, so maybe something is going right for a change.

Much is owed to all the help I got here, thanks again.

Al