Sanding stuff

[James Giordano]

This may be dumb but......
I hear some talk about sanding things wet.
Can anyone explain to me why and when?:confused:

[Ernie Kuhn]

James, not dumb.
I'll speak to what little I know. Some turnings, when done with your "normal" progression of sanding e.g. 120 grit, 240 grit, 400 grit are usually "dry" sanded. Beyond that, when going to ever finer sanding, I use wet or dry sandpaper from auto supply house like Schucks, Al's, whatever. I sand "wet" meaning I put a little Danish Oil in a plastic cup and dip sandpaper in it before sanding. Seems to give a smoother finish and do a little grain filling at the same time. For acrylic pens, I use the same process e.g. wet or dry sandpaper but with water instead of oil. In both cases, it makes a bit of a "slurry". I presume you can do the same with flatwork, with the penetrating oils or boiled linseed oil (BLO), especially if you wrap the sandpaper around a block.
I'm sure others with a lot more experience than me will chime in.
Ernie

[Dennis Peacock]

Good question James!!!!!

Wet Sanding.....any sanding process that you do with wet/dry sandpaper that you "lubricate" with some medium that does not attach the finished surface. Poly or Varnish, you can wet sand with lemon oil. Shellac, you can wet sand with mineral spirits (after the shellac has dried). Some even wet sand with mineral oil or water...just depends on what the finish is and what you can use to libricate the sanding with that won't attach the finish. An example of what NOT to do is wet sand shellac with denatured alcohol or varnish with mineral spirits as these will begin to melt the topcoat.

Make sense?

[James Giordano]

So the reason to do this is..... to help fill in pores and/or to get a shinier finish?

[Dennis Peacock]

Not necessarily fill in pores but to level the finish, remove dust nibs and such that dried in the finish and give you a nice smooth surface. You can make it a shinny surface if you used a gloss finish. You can even make a gloss finish Semi-Gloss if you buff the finish with some 0000 steelwool or something equivalent with a little lube and then wipe dry and clean. I buffed out our kitchen table I made with 0000 steelwool and Johnson's Paste Wax and that took a little of the gloss off and provided a nice even wax coat for added protection.

There is a sanding process that is "wet" with a wash coat of the clear finish that will aid in grain filling but I've never done it. You're basically sanding with 220 or 320 grit paper and a highly thinned (50/50) mix of thinner and the actual clear finish...apply sparingly and sand really well....let dry and sand with the next higher grit..lightly though. Wipe clean or vacuum and apply your series of clear topcoats after that.

[James Giordano]

Thanks Dennis


I actually have tried doing this with the steel wool and BLO,Poly,mineral spirits mix because I had read about doing that somewhere. I just wasn't sure why I was doing it. The finish came out looking pretty good in the end on a piece of scrap cherry:) I'm going to try it on my current project and see how it goes.