Official Luthiers Forum!

Hello all,

I hope I can get your collective advice. I'm about to start finishing a coffee table for a dear friend. The wood is a burled walnut with some fissures and cracks that give it real character.

After alot of testing I am going to build the finish with the following general steps:

Dry sand to about 240 grit, raise grain and cut back with 320 grit
Apply an aniline (water based) dye to warm the wood, bring it into a good color complement with the legs
Apply 2-3 coats of shellac (very blonde, dewaxed). This is partly to "smooth over" the fissures, partly for acting as a vapor barrier as due to the design I want very little expansion/contraction of the table top stressing the leg joints.
Topcoat the shellac with 2-3 coats of polymerized tung oil

I want to achieve a high gloss finish which I do not usually aim for, so I am going to move into unfamiliar territory and abandon my usual practice of levelling between coats with 600 wet/dry sandpaper and rubbing out the final finish with 0000 steel wool.

I have at my disposal the following:

"standard" finishing stuff (sheet sandpaper up to 1500, 0000 steel wool, pumice, rottenstone, white spirit etc.)
Some newly purchased stuff I thought I could use on this project:
A set of Micro-Mesh sanding discs for my RO sander (1500-12000x)
Two Surbuf pads for my RO sander


The reason I give what I have on hand at the moment is that I don't live in the States anymore so it is tough for me to get anything else easily (i.e. some of the posts and amazing guitars I've seen here have been talking about this or that polishing compound and I want to say I wont be able to source that locally). Basically I want advice here about how I can best use what I have on hand to get this finish done as best I can.

So my question is basically what approach to people think I should take to levelling and polishing my table top to a high gloss finish?

Based on my reading I am inclined more to go with the Micro-Mesh rather than the Surbuf pads, and to use the 1500 up to 3200 Micro-Mesh pads in between the shellac and tung oil coats to level, and then buff the final coat of tung oil with 4000 through 12000 grits of Micro-Mesh.

Do people have other thoughts? Also, would people recommend using water/water with dish soap/white spirit or some other agent as a lubricant with any of this? Keep in mind the table top is heavily fissured in places so I'm a bit concerned about any gunk getting down in those cracks and being visible after.

Really hope some of you guys can help me out - I am feeling a bit out of my depth on this one.

Thanks so much,

Suzanne

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Que la vie est belle....

Suzzane

I think you can get the high gloss you are looking for with the MicroMesh and wax.
Once you have the final coats on, MicroMesh up to 12,000 and then apply the wax. You will have the issue of the sanded finish getting into the fissures and cracks, but if you dig it out while it is still wet, or blow it out with compressed air, you should be OK.
I have never wet sanded tung oil, polymerized or not, with MicroMesh, so I do not know how it reacts to being wet sanded. However, you can very easily use MicroMesh dry, which will alleviate most, if not all, of the issue of the sanding slurry getting into the fissures. The dry powdered finish should easily blow out of the irregularities in the surface.
I have to say that if you are going to mention a beautiful piece of wood around these parts, you might want to post a picture of it. I for one, am always interested in some good wood pics.
Hope your project turns out great and do post pics of the finished product as well.

One more thing, Turtle Wax has a product line called "Ice" which will work very well for your table with its surface irregularities and fissures. It is a clear wax that leaves no white residue when dry so if you are unable to remove it all, you will not have ugly white residue in the fissures to try to clean out. Since it is made by Turtle Wax, I would imagine it it not to hard to get anywhere in the world.
Good luck.

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http://www.CostaGuitars.com
PMoMC

Thanks Tony for the quick response and ideas. Still keen to hear other views.

I'm attaching an early shot of the slab....not much for taking photos so no more recent shots but you get the idea.

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Que la vie est belle....

Suzzane

You are going to need more than 3 coats of finish to achieve a high gloss, a lot more.

Also, you will need some type of buffing compound to get the gloss. Sandpaper will only take you part way.

Thanks Filippo, Barry and Tony.

I've never done a French polish finish before - I have a great finishing book by Bob Flexner that describes it and on the surface it doesn't sound too complicated so I was tempted here. However, a friend who works in furniture refinishing here says there are lots of small things that make or break it and that there really is quite alot of knowledge one picks up over time. So....I've kind of ruled out learning on this project as it is going to a friend.

Based on what I've taken on board so far I am planning on sticking with my original plan of levelling shellac coats and the tung coats with Micromesh (up to 3200). I'll increase the number of polymerized tung coats I apply to around 6 or so from the 2-3 I had planned. I'll then keep my eyes open for a buffing compound I can use dry here as I really don't want any crap falling into those open fissures. I'll buff that using my Micromesh pads up to 12000. Finally, I'll apply paste wax (I have a good one but will also keep an eye out for the Turtle Wax Ice product) and buff that as well at 12000.

Thx for everything guys....as for why I posted here...I love guitars and hope to make my own one day. I've lurked here for a while and remembered seeing a number of discussions on going for a high gloss finish so made sense to me

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Que la vie est belle....

Suzzane

Hi, Suzanne,
Barry and Filippo have given the best advice, in my opinion. Whatever top coats you use (and you could use almost anything on top of shellac), I think it needs to be a hard finish. I think you need something harder than tung oil. French polish, lacquer, hard oil varnishes (like spar varnish) and many other finishes can yield a high gloss finish. But I don't think tung oil will get you where you want to go.

Do a little experimenting on scraps while you're thinking this over. Make your choice, and build a surface finish that is several coats thick. Wet sand it level, using a lubricant like mineral spirits or even soapy water. Set it aside to cure again for a few weeks because the wet sanding will soften the finish. Once it's cured, work your way patiently through your micro mesh pads and don't skip any pads in the process. You can achieve a mirror-like effect with a hard surface film, some elbow work, and some patience.

Please post a follow up so we can all see your beautiful table when it's finished. Good luck with it!