Finishing a finish

[Dave Cohen]

What schedule do you guys follow to finish your finishing?

Meaning: after you've put on your 2 or 3 or 6 or 10 coats of varnish or polyurethane, what do you do next, sand it out with 0000 steel wool or 3000 grit sandpaper, then buff it out with paste wax, just looking for ideas to make the final touches on the finish so it looks its best.

Thanks in advance.

[Steve Schoene]

If I am doing the full shebang rub-out, I make sure that the surface is fully leveled, with 320 grit on the penultimate coat. Then I let it cure for several weeks to allow any shrinking of the varnish to occur, and re-level before applying a final coat. Then I wait as long as I can stand it, at least another couple of weeks for the varnish to cure and harden. At this point you can't be aggressive since you must complete the rub-out in the thickness of that last coat. If possible I start with 600 grit, and then go to about 1200 grit. (CAMI) more like P2000. For satin, 600 grit may be fine enough, and pumice or rubbing compound can remove the scratches. For a gloss finish, I go directly from the 1200 grit to rottenstone but a polishing compound would also work.

I do not work my way through the grits. That's "more effecient", but unless you know exactly when to stop sanding with each grit, it will remove more material and increase the risk of cut through.

Steel wool doesn't level finishes. sand paper is much better for that. The role for steel wool, if any, if for creating a final satin finish, with it often lubricated with wax. I tend to use rottenstone lubricated with parafin oil for a final gloss sheen. It gives high gloss, but not patent leather shiny. For satin, I use 4F (the finer grade) pumice.

[Jamie Buxton]

I hardly ever "finish a finish". I aim to get a perfect finish from the application. That whole business of sanding out brush marks or orange peel is required only if you leave marks in the finish with your applicator.

I also never put a mirror finish on wood furniture. Wood has pores and grain. That's part of the wonderful natural material I love. I want to see that texture, not a plastic layer covering it.

[Steve Schoene]

That does pretty much rule out varnish. Apply it perfectly, but unless you have a "clean room" there is something to deal with in the end.

Perfection is the enemy of the good. Feeling like you must achieve perfection in application can be very intimidating and can limit folks to oil/varnish, a good choice in many cases, but still quite limiting. But when the option of rubbing out the finish is available, horizons open up and merely good finishes can become excellent ones.

The question of whether to have a full filled finish--glossy or satin--is an aesthetic one, there is no right and wrong. I often make 18th. century reproductions. The originals almost all have full or nearly full filled pores. Perhaps not all of them had originally, but they sure do now. Other styles would look wrong with those finishes.

[Prashun Patel]

I'm a novice, but have found rubbing out a finish to be difficult. You gotta have PATIENCE until you refine the technique.

Coupla tips from a novice:

I've found polyurethane and spar varnish are hard to rub out. That is, it's hard to achieve a uniform scratch pattern and really hard to bring it up glossy.

I've found it easy and cheap to simply let the final varnish or shellac or poly coat cure (2 days for shellac, 2 weeks for varnish) and then rub with 0000 steel wool and paste wax. Rub the wax on fairly aggressively - you want to abrade off any nibs. Don't let the wax dry too long, then wipe and buff. Repeat if necessary. I find it brings the gloss down and accentuates the WOOD - not the finish.

IMHO, the most important thing finishing the finish does is make the surface baby-butt soft and smooth. I've yet to get this without finishing the finish.

[Joe Cunningham]

I hardly ever "finish a finish". I aim to get a perfect finish from the application. That whole business of sanding out brush marks or orange peel is required only if you leave marks in the finish with your applicator.

What finish do you generally use?

Varnish looks much better with at least some finishing of the finish IMO. I've done the full rub-out to achieve a gloss finish and I loved the way it turned out as it really highlighted the best of the wood.

I don't have spray equipment, so I've never worked with the lacquers. Can you get a perfect finish straight from the gun? Even shellac seems to look better with a bit of rub-down with 0000 wool and wax.

[Dave Cohen]

then rub with 0000 steel wool and paste wax.
Do you rub the wax in with the 0000 steel wool, or rub with 0000 wool then separately rub in wax?

[Prashun Patel]

I rub the wax in with the wool, then wipe off with a terry cloth rag, then buff with a clean rag.

[Jim Becker]

II've found polyurethane and spar varnish are hard to rub out. That is, it's hard to achieve a uniform scratch pattern and really hard to bring it up glossy.

Makes absolute sense. Spar is a long oil varnish and is relative soft so it can be flexible--spars bend. Hard to rub out something like that. Polyurethane is designed for abrasion resistance, so it's naturally adverse to rubbing out which is by nature, abrasion. Neither of these products is a good choice for furniture that you want to be able to rub out...IMHO, of course.

[Dave Cohen]

Jim,

What product do you think works well for getting a nice rubbed out finish?

[Jim Becker]

What product do you think works well for getting a nice rubbed out finish?

The harder the finish the better for this. Non-poly varnishes, shellac and lacquer will be in that category. Note that you should wait until you have a full cure before you do any rubbing out for best results. That's measured in weeks to a month or so for the "full" cure.

[Tony Bilello]

Throughout the ages, artisans and fine woodworkers perceived the 'perfect finish' as a mirror finish. it should look like you are looking through glass. In the past, the closest they could get to this was by using shellac.

Today, nitrocellulous lacquer and shellac are pretty much still
achieving these goals. Keep in mind that there is a difference between looking through glass (lacquer and shellac) as opposed to looking through plastic (poly and most other varnish type finishes).

I spray lacquer because of the durability, speed, ease and drying time.
Nitrocellulous lacquer is the staple finish of the furniture industry and has been for almost 100 years. It is very good stuff.

Prep is everything when it comes to finishing. If you want a mirror finish you must use a paste wood filler to fil the grain first.

Because Lacquer is a solvent base, you can thin it out quite a bit. You can get a really fine finish straight from the gun. Generally, the only time I rubbed out a lacquer finish with pumace and rottenstone was when a 'piano' finish was required. I am a big proponent of lacquer. You can spray it tonite and rub it out tomorrow morning.

If you really want to see the wood grain, high gloss is the way to go. If you want to subdue the light which also subdues the grain, go with satin.
Anytime you diffuse the light as with satin finish, you are also 'hiding' some of the grain.

As for gloss or satin finish, that is strictly up to the persons own individual taste.

Most often the choice is based on "how long do i want this project to sit around in the shop" and "does anyone else really notice the difference or even care".

Thats enough ranting for now. LOL

[Jim Becker]

Tony, I do agree that solvent based lacquer provides a very, very nice finish. The issue for many, however, it that it's not really safe to spray in the environments we have available, both from a health standpoint and from an environmental/fire hazard standpoint. Fortunately, the acrylic finishes (water bornes) have been improving a great deal over the past few years and that means more and more folks can get a better sprayed finish out of the gun without the risks associated with spraying solvent based products. More and more folks cannot buy/use the solvent based products anymore, too, due to VOC regulation.

[Howard Acheson]

>> I've found polyurethane and spar varnish are hard to rub out. That is, it's hard to achieve a uniform scratch pattern and really hard to bring it up glossy.

And the reason is that urethane is added to varnish to improve it's scratch resistance. "Rubbing" is sanding and sanding is scratching. Because of the scratch resistance of poly and the softness of spar varnish, they do not lend themselves to being sanded. You will never be able to rub to a gloss higher than that directly off the brush.

The rule is "the harder the finish (shellac, lacquer and some waterbornes) the better they will sand."

[Rich Enders]

If I am doing the full shebang rub-out, I make sure that the surface is fully leveled, with 320 grit on the penultimate coat. Then I let it cure for several weeks to allow any shrinking of the varnish to occur, and re-level before applying a final coat..............

Steve I have a question. Leveling out a shellac finish was taking forever, so I tried using a random orbit sander with a synthetic pad. I used a "Very Fine" pad that came with the Bosch sander. It seems similar to the gray pads from 3M. It seemed to work perfectly, and the first coat of waterborne lacquer looks good.

Do you have any concerns here?