Wet Sanding

[Stampy]

Anybody have experience wet sanding?

Can you wet sand raw wood to pop ther grain?

And does the type of finish you plan to use dictate whether you wet sand or not?

Thanks

Stampy

[Bombarde16]

"Popping" the grain is a finishing technique used on figured woods. I believe you mean "raising" the grain: Just before finishing, wipe the surface of the wood with clean water and wait. After the wood dries, it will feel rougher because surface fibers have swelled. Knock these back with a fine sandpaper and you're ready to apply whatever finish you desire. As to which type of finish? It's a good habit for any finish, but is particularly important any time you apply something that is water based.

This however, isn't wet sanding. It's wet...then you sand. Wet sanding is a technique for keeping dust from flying into the air, primarily used IIRC in auto body work. Keep the surface wet and the dust stays trapped in a slurry, instead of ending up in your lungs.

[Stampy]

I'm familiar with both of those processes,

What I was wondering is if anyone has ever wet sanded wood?

Or a coat of finish that has been applied to wood?

Stampy

[kep1019]

I never have wet sanded raw (unfinished wood) with water, and I would be afraid to because of the concern of introducing contaminents into the pores from the sandpaper.

That said I have wet sanded oak with oil to fill the grains idea being the sawdust is capured in the oil and fills the pores sqeegy the excess off across the grain. I have also wetsanded after finishing to smooth out as a first step to buffing out the final finish with wax.

keith

[Stampy]

All right. That souds like something worth trying.

What grain of paper did you use 400 or higher? Was that tung oil or linseed oil you used?

Thanks

Stampy

[AceHoleInOne]

Stampy...what exactly are you trying to do? Popping the grain? What woods are you working with....come on let it all hang out :)

We will do our best to help out!

-Ace-

[Stampy]

Stampy...what exactly are you trying to do? Popping the grain? What woods are you working with....come on let it all hang out

This all started when I was looking for some 1000 grit sand paper the other day and the clerk at the shop asked if I wanted wet or dry paper (yes its a woodworking store). Then I got to thinking this might be a good idea if you were doing it between finishing coats to keep the dust to a minimum. Now that I think of it, dealing with the slurry might be a bit of a challenge. And create more of a mess than I'd want.

I have done the grain raising technique several times and it works great. But maybe you could do raising the grain and sand at the same time.

Just thinking here.

So has anyone tried any of these?

[Don Z.]

OK, I'm willing to be corrected if I'm wrong, but 1000 grit on bare wood? You should be applying finish well before that. With finish on, wet sanding makes sense. But 1000 grit on bare wood?

[AceHoleInOne]

I pick up what your laying down Stampy.

Good that you have the wheels turning. I think you answered your own question. I have been guilty, sometimes, I wet the wood (piece) down with a spray bottle to raise dents and cross grain scratches from handling, then I will wipe back with a dry rag and go at it with my sander. Just be careful. Sometimes if the wood is to wet, the dent is proud, you sand it off, as the wood drys, the dent will shrink back below the surface and becomes noticeable.

Umm, I don't see a any time saving, I guess it would help keep the dust down. But imagine the slurry left behind in the grain of the wood when dry. Also the wood will probably cup, twist, bend from being so wet.

Now as for popping the grain sanding dry with high grit paper. Sure sanding your tiger maple with high grit paper will bring out the grain, however, you would probably then want to shoot a water white (finish that wont amber) type finish over it, say accent wood for a jewelery box. If your going to add color. Sand normal through the grits to 150/180/220...it all just depends.

When to wet sand a finish...so long as the finish manufacture advise it can be wet sanded (some water-based finishes makers say don't) is due to uneven application, runs and nibs. Usually wet sanding is done trough the mid-coats when the finish build is thick enough to sand.

-Ace-

[Vic]

My guess is that the reason the clerk asked "wet or dry sanding" as a response to your looking for 1000grit is that would be used as an intermediate grit for sharpening your chisels/blades etc. I can't see any advantage to wet sand wood unless you're already in the finishing mode to fill or buff.

[Stampy]

OK, I'm willing to be corrected if I'm wrong, but 1000 grit on bare wood? You should be applying finish well before that. With finish on, wet sanding makes sense. But 1000 grit on bare wood?

Sorry if I wasn't 100% clear there don...I don't use that on bare wood.

Usually start at 150 with the palm sander then hand sand from there up to the finer grits.

[Stampy]

Yo Ace;

That was some kickin' advice about the grain popping, and the mid coat sanding.

I might have to try a few test pieces of this before I try it on an ongoing project.

Thanks to all for the input.

Go Canucks Go...Kicked some Dallas butt tonight

Stampy

[Don Z.]

Sorry if I wasn't 100% clear there don...I don't use that on bare wood.

Usually start at 150 with the palm sander then hand sand from there up to the finer grits.

OK, but at what point do you stop with the bare wood sanding and apply finish?

Rebecca Whitman goes into detail on applying varnish after grain filling with oil sanding. But I believe she stops around 220, and then goes with a 50% thinned varnish, then 25% thinned, then full strength for about 8 coats. Between coats is a quick rub with 320 grit. Possibly, after 10 coats, one could go to rubbing out with mineral oil and rottenstone or pummice. But 1000 grit is really up there, no matter how you slice it.

[Vic]

OK, but at what point do you stop with the bare wood sanding and apply finish?

Rebecca Whitman goes into detail on applying varnish after grain filling with oil sanding. But I believe she stops around 220, and then goes with a 50% thinned varnish, then 25% thinned, then full strength for about 8 coats. Between coats is a quick rub with 320 grit. Possibly, after 10 coats, one could go to rubbing out with mineral oil and rottenstone or pummice. But 1000 grit is really up there, no matter how you slice it.

Don, I wouldn't go higher than 220. I think Marc usually stops at 180. Much higher than 220 and the finish won't absorb into the pores. The Sutherland Wells Polymerized Tung Oil I like specifically says not to sand above 220.

[Don Z.]

Makes sense. I go to about 180 bare, 220 on the first coat, then 320 or so. Not a lot of sanding between coats, just enough to give it a little "tooth". I don't think I'd ever bother with 1000 grit. I haven't tried rottenstone yet, but mostly this is on boats, so it really wouldn't be worth the time. Only reason I can think to have 1000 grit in the shop is scary sharp...

[Pete Bennett]

This all started when I was looking for some 1000 grit sand paper the other day and the clerk at the shop asked if I wanted wet or dry paper (yes its a woodworking store). Then I got to thinking this might be a good idea if you were doing it between finishing coats to keep the dust to a minimum. Now that I think of it, dealing with the slurry might be a bit of a challenge. And create more of a mess than I'd want.

I have done the grain raising technique several times and it works great. But maybe you could do raising the grain and sand at the same time.

Just thinking here.

So has anyone tried any of these?

I am not surprised you were asked do want wet or dry paper. Because that is exactly what it is known as. Wet or dry is usually silicon carbide and is especially manufactured to be used either wet or dry, hence the name. I regularly use it from 500 grit upwards, but never ever on bare wood. I doubt you can get ordinary glass paper that fine anyhow. Maybe some of the Aluminium Oxides, though I've never seen any.

I've tried several methods over the years and some of the super hard woods like Apple or Lignum Vitae will come to a soft sheen with 600 grit, but on normal furniture woods you're just wasting your time. For Oak I rarely go above 180 and for maple I stop at 220. From there on in I denib and generally lay off the surface to an all over matt finish between coats until I have as perfect and flat a surface as I can get before final finishing. Depending on the wood, the project and the finish I'm after (matt. satin or high gloss) I'll go as far as 1000 or some times 1200. But most often when I get past 600 I go for rotten stone.

I only go beyond this if I'm giving a vitriolic finish to French Polish, and thankfully that is now a very rare request.

[kep1019]

Sorry was away for awhile, For filling the grain I use 220 with oil and actually I used WATCO danish oil blend and used that for the final finish also.

Keith

[mdbuilder]

Wet sanding a film finish is indicated any time you try and dry sand and the finish corns on the paper. Use a few drops of dish soap in the water, mop up the mess with a paper towel periodically.