Wet Sanding - Calling Wally Dickerman

[Prashun Patel]

Last year, WD wrote a great thread about oil sanding on the lathe. I've been trying with mixed results. It seems I cannot figure out the RIGHT amount of finish to put on the wood. Too little, and it doesn't do anything; too much, and it gums up the paper too much. I have come upon two methods that seem to work better for me, and wanted to see if others have tried this or nixed it.

1) Using DNA to sand. I wipe it all on, and let it evaporate until the piece is fairly dry to the touch (< 5 mins). Then I sand. I get 'thick' dust clumps instead of fine sanding dust. It FEELS like it's cutting more aggressively than dry, and - here's the best - it does not clog the paper as quickly as when I was oil sanding.

2) Use MS to sand. I wipe it on thin, then let it dry - (usually overnight) - and I get similar results as 1. If I try to sand too quickly, I get the same results as oil/varnish sanding - clogging, and repeated clogging even after a couple sheets.

My intuition is that Wally, you have achieved similar/better results using finish, but I can't see going through 3-5 discs on each grit. What am I doing wrong? And since DNA is so much cleaner and quicker to use, why not just use that? It also lets me see scratches from the prev grit nice and easy.

[Wally Dickerman]

Hi...It appears that you're oil sanding using power. I do my oil sanding by hand sanding. I use finishing oil..the same as I might be using to finish the piece. I apply the oil using a folded paper towel and with the lathe running. I don't soak the piece. I'll usually re-apply the oil once or twice. Whatever it takes. I oil sand only with the initial grit. Depending on the wood and the surface that's left by the tool, I might start with 120 or 180 or even 220. Yes it clogs the sandpaper quickly but oil sanding is very effective. Been doing it for a lot of years.

A lot of turners slow the lathe way down for sanding...I don't. If I'm turning an 8 inch vessel at 1800 I might slow it to 1200 or 1400 for sanding..or sand at 1800. Just keep the paper moving so there's no heat buildup.

Oil works well for shear scraping on a piece with tearout.

[allen thunem]

Prashun not to sound stupid but maybe you could elaborate a bit more on the type of paper you are using.
Wally maybe you could do the same?

[robert baccus]

Oil wet sanding works well for me but only on very hard woods. on the really hard tropicals, lighter pine, ect i often sand with slightly soapy water. these woods are usually waterproof for a short time. sometimes i dislike oilsoaked tropicals--too dark and this allows more finishing options.---------------old forester

[robert baccus]

PS. Like Wally i wetsand on the lathe--perhaps slower.

[John Beaver]

Depending on what the final finish will be I use 2:1 or 3:1 Minerals Spirits and BLO. or shellac sanding sealer.

[Carl Civitella]

I use mineral oil or spirits with 220/400 black auto paper. I flood the paper with oil, i never noticed any paper clogging up with dust. I sand by hand at medium speed. I have been using Abranet lately on different tasks, but never wet, i wonder how that sands wet? Carl

[Prashun Patel]

Just an update. I've been trying Wally's technique for several vessels now, and have hit upon a breakthrough for myself. When the piece is fresh with finish, the first couple pieces of paper will clog fast. However, I realize this does not mean they are worn and need to be discarded. I found that a quick brush with a wire bristle brush cleans the disc and extends its life many times. In fact, you can even just keep the sander on, and run the clogged paper right on the brush for a second. Anyway, it's really helped me get good results with 80 and 120 so far. Thought others may like to know.

[David DeCristoforo]

Well it sounds to me like you are not "wet sanding" at all. Allowing the lubricating material to dry before sanding seems counterproductive. The whole point of wet sanding is to use the liquid, whatever it is, to lubricate. Wet sanding is really more of a polishing process than a sanding process and should be done with very fine abrasives... 400 or finer. If your getting "gumming" it's probably because you are allowing to material to dry too much before sanding.

[Prashun Patel]

David, this is a different technique from typical wet-sanding. I agree; at higher grits, the liquid is used as a lubricant to keep the paper from clogging. But Wally wrote a while ago about oil sanding at low speeds and low grits as an efficient way of sanding thru the initial grits. Here, it seems more the idea is to make the wood somehow more susceptible to abrasion by wetting it, ultimately improving sanding efficiency at the coarsr grits. I am unclear of the reason, but have gotten it to work a couple times.

[Reed Gray]

Hmmm. I have tried it a time or two. I do power sand, and the discs do clean up easily with the eraser sticks. The main problem I have had is that the slurry tends to clog up marks and defects in the wood so that they are masked until I am up another grit or two. I have just found it easier to let the wood dry first, then sand. Slow lathe speeds are necessary for warped pieces, in the 15 to 20 rpm range.

robo hippy

[Paul Williams]

I wet sand after I have dry sanded to 220 or 320. Allways with the lathe running. I apply BLO from a squeeze bottle onto the wood holding a piece of 400 sandpaper below it. After sanding with the BLO I add some shellac and continue sanding, sometime with the next higher grit. Then I use a rag or paper towel to clean off any extra and burn the BLO & shellac into the wood. It does a good job of filling open grain wood, and provides a nice base coat for tight grain or open grain wood.