Maloof type finish - help

[Ron Moreland]

First post and I really need help. I am attempting to finish 25 y/o walnut with an oil/varnish/thinner mix. 4 parts high gloss varnish, 3 parts BLO, and 3 parts spirits. Sanded to 220, flooded on finish, waited 15 to 20 minutes, wiped off throughly, let dry overnight, same again the next day. Then I started wetting surface and sanding with 320 wet/dry paper, wait for a while, wipe off completely and let dry overnight. Next day sand with 400 wet/dry, etc. Then 600 and 800. The grain is filling in nicely but I have a very blotchly surface - some places with a bit of shine but most everywhere else is dead flat and it has streaks. I have scrubbed the surface with 0000 steel wool to an even flat before sanding and I have stripped the entire surface back to bare wood and started over. Still comes out the same. I have used the oil and sanded very lightly and other times have sanded with quite a bit of effort. I understand that I will never get a glossy finish but think I should get some even level of sheen across the entire surface. Any suggestions or recommendations?

[glenn bradley]

Some of our finishing experts may have a better answer but, varying gloss usually indicates that the finish is not well mixed IME.

[Brian Kent]

What kind of furniture is it?

I recently finished a walnut burl table. Because of some problems with my technique, the table was not utterly flat. I had to find a solution that would allow for slight variations in the surface. Until I did, there were dull and shiny spots left by the fine sanding.

I finally found a solution in micro-mesh cushioned abrasives on a random orbit sander. The cushion allowed for that very slight waviness in the surface. The very high grit levels (up to 12,000) allowed a lot of control for the sheen. They are $20.99 at Rockler:
http://www.rockler.com/product.cfm?p...lter=micromesh

I used mine on a Waterlox original finish after 30 days of curing.

Good luck to you.

[Scott Holmes]

Glenn, We have experts here?

Ron,

Brian's solution is great IF you were using a varnish as he did. You are not; you are using an oil/varnish blend... a.k.a "Danish oil". This is an in the wood only finish.

I noted that you said "25 year old walnut." Is this a piece of furniture that you are refinishing? If so sanding will not remove the old finish from the pores and you will get a mottled look. a.k.a. blotchy...

A chemical stripper is the best way to remove old finish.

[Steve Schoene]

Then I started wetting surface and sanding with 320 wet/dry paper, wait for a while, wipe off completely and let dry overnight. Next day sand with 400 wet/dry, etc. Then 600 and 800. ?

When do you mean wetting it with the oil/varnish mix, or with water?

[Scott Holmes]

Ron, Are you wet sanding with water?

I assumed wet sanding the oil/varnish blend.

[Chris Fournier]

Without pictures I can't be absolutely certain but I think that you are getting too aggressive with the sanding while not having enough of a finish film.

You're wiping on a finish, not spraying or brushing, you really don't have enough film to sand as you are presently doing. Instead I'd wipe, let cure and then use a scotch brite pad to take off the raised grain and nits and then re-coat.

You'll have to apply several coats to get a film that has a consistent sheen given the application technique.

[Scott Holmes]

Chris,

You can't build a film with an oil/varnish blend. It's an in-the-wood-finish only.

[Chris Fournier]

Chris,

You can't build a film with an oil/varnish blend. It's an in-the-wood-finish only.

I simply can't understand how you can think that this is the case Scott.

Varnish consists of solids (resin), drying oil and a thinner/solvent and consequently builds a film. If you have a finish with varnish as a component you can build a film. The oil and solvent don't magically dissolve the solid content. I have built film finishes with oil/varnish blends for years as has everyone else that uses this finish. This is fundamental stuff, certainly as a teacher of wood finishing you know this to be true.

[Scott Holmes]

Chris,

Try this simple little test. Spread a few drops of varnish on a piece of glass. Next to it but not touching it, spread a few drops of an oil/varnish blend on the glass.

Let it dry for a few days and check and see how "hard" the varnish film is vs. the the oil/varnish blend film. Yes you can build a film with an oil/varnish blend but not a hard, durable film. You will be able to scrape the oil/varnish film off with a fingernail; not so with the varnish.

Modern Varnishes are not oil, resin and solvents mixed into solution... they are processed and the heating and "cooking" of the oil and resin produces a new molecule called varnish, the old fashion spirits varnishes and the oil/varnish blends are similar but not the same. The new varnishes mixed with oil do not dry to a hard film, more of a rubbery film.

[Chris Fournier]

Chris,

Try this simple little test. Spread a few drops of varnish on a piece of glass. Next to it but not touching it, spread a few drops of an oil/varnish blend on the glass.

Let it dry for a few days and check and see how "hard" the varnish film is vs. the the oil/varnish blend film. Yes you can build a film with an oil/varnish blend but not a hard, durable film. You will be able to scrape the oil/varnish film off with a fingernail; not so with the varnish.

Modern Varnishes are not oil, resin and solvents mixed into solution... they are processed and the heating and "cooking" of the oil and resin produces a new molecule called varnish, the old fashion spirits varnishes and the oil/varnish blends are similar but not the same. The new varnishes mixed with oil do not dry to a hard film, more of a rubbery film.

Scott, you are simply incorrect. I have been doing the "impossible" according to you for years now. Todays solvent based varnishes mixed with oil will indeed form a hard film. In fact the resultant film of an oil/varnish blend is hard enough to actually buff/rub out. Have you actually tried this technique? I have, and a hard film is the result.

Honestly, if you just use BLO and apply enough coats you can develop a film that's more than just "in the wood" as you put it. Is it durable or terribly hard? No it isn't, but it is indeed a film on top of the wood.

[Pete McMahon]

Chris, there is some hair splitting going on. Will a mixture with a varnish component produce a film, yes. Will the mil thickness and degree of film formed take longer to build, yes. Are oil\varnish mixtures generally employed for a close to the grain (or non film forming) look, yes. To split a few more hairs even wax can be considered a film in a microscopic way. A good gloss can be achieved on this "film" with some judicious buffing.

The other point about flat surfaces; I believe the point Scott was trying to make was a wood surface, whether it be round, carved or flat, should be made flat during surface prep. That means possible undulations at the surface level should be made flat. In the end, you will have a more perfect finish than starting with a surface prepared with less care. Once the film is formed can it be buffed out to a high gloss? Yes. I've buffed out surfaces to a very high gloss that weren't perfectly flat at the surface level. Most times it's acceptable. For those perfect jobs, is it all about the prep? Yes.

[Chris Fournier]

I'd say that we are actually very far from splitting hairs here. Perhaps your point about wax could be construed as hair splitting when it comes to the "film topic" but I understand that you are using it to make a point.

I do believe that there will be no consensus!

[Scott Holmes]

Chris,

Try the test on glass. I have a sample I pass around class and the differene in "hardness" between the dried varnish and the dried oil/varnish blend is dramatic.

Boy did we get this off topic... I hope the OP isn't afraid to ask another question.

[Chris Padilla]

Honestly, if you just use BLO and apply enough coats you can develop a film that's more than just "in the wood" as you put it. Is it durable or terribly hard? No it isn't, but it is indeed a film on top of the wood.

I guess I'm not used to thinking of BLO as a film finish but I guess one would need to DEFINE what constitutes a FILM FINISH. I can only look what I consider one of the bibles on wood finishing from Mr. Bob Flaxner, "Understanding Wood Finishing", and suggest we use his definition although that might not be easy either!