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Bill Wiggins
04-07-2005, 5:37 PM
What should be used for wet sanding? I've seen one suggestion of soapy water and another suggestion of the BLO/Thinner/Poly mixture. I tried the mixture and it seemed to bind the sandpaper. Was difficult to use with sandpaper but worked OK with extra-fine steel wool.
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Bill Smith

Jim Becker
04-07-2005, 7:20 PM
I wet sand with just BLO. That creates a slurry that fills small pores meanigfully since the oil cures. I would never "sand" wood wet. Once there is shellac or a varnish on the piece, if I want to "wet" sand, I just use some mineral spirits as a lubricant and use wet and dry paper, usually 400 or finer, depending where in the process I am.

Jeff Sudmeier
04-08-2005, 8:32 AM
What are the advantages of wet sanding? Where should it be used and not used?

Jim Becker
04-08-2005, 8:47 AM
What are the advantages of wet sanding? Where should it be used and not used?

"Wet" sanding is used for different purposes at different times. When used with an oil or varnish oil, it can be used to do some grain filling as the slurry you create gets packed into the tiny voids and stays there as the oil cures.

"Wet" sanding a reactive finish (varnish, for example) or an evaporative finish (shellac and lacquer) after they are cured provides some lubrication, making for a better polish. This is usually done with very fine materials, both paper and micromesh. And you can easily wipe off the slury during the process, too. I use mineral spirits for this purpose. (One should always clean off the surfaces between grits to avoid scratching from "break-away grit" from the previous step)

Bob Hovde
04-08-2005, 3:49 PM
Jeff,

If you are fine sanding a finish, the paper will clog up almost immediately. By using a lubricant (water works fine if you're sanding a FINISH and not WOOD), it keeps the grain of the sandpaper clear. If you are leveling a varnish prior to rubbing it out, wet or dry 600 grit works great. (Does anyone else still "rub out" a finish? I do it because I'm such a lousy finisher in the first place. :( )

Bob

Jeff Sudmeier
04-08-2005, 3:57 PM
Thanks Guys! This new forum is GREAT!

Dennis Peacock
04-08-2005, 4:47 PM
Jeff,

I wet sand on the lathe a lot. I use mineral spirits soaked shop towel and apply it to the slowly spinning wood. I then place the sandpaper on the opposite side of the MS soaked rag so that the MS gets to the paper quickly and helps to float away wood particles. When using fine grits, I have found it good to sand wet and then hand sand less wet and let it dry. The MS helps the wood surface be softer to cut, provide a lube to the paper and drastically cuts down on the airborne dust particulate. Besides that, after wet sanding, the surface has a feel of being as slick as glass. ;)

Just my 2 worth.

Alan Turner
04-08-2005, 4:53 PM
Bob,
I still rub out just about every finish I use. That way I can control sheen.

Carl Eyman
04-08-2005, 6:08 PM
I'm with you, Bob. I love a varnished finis that has been rubbed out. Come to think of it, I've never rubbed out any other kind. With the pads and abrasives one can get for the ROS now it is no longer a big deal.