sanding green turned bowls

[Ivan Stancioff]

I recently started turning maple and chestnut when its green and wet. I find the turning to be very easy and the result, after drying, very interesting. I would like to know what people use for sanding the wood when green. I find it far more awkward to sand them after they are dry and can no longer be mounted on the lathe.

 

[Dean Center]

Me, too. I'll be interested to get some pointers from responses to your post. Thanks for asking.

 

[Richard Coers]

I turn my green wood bowls relatively thin. I use the method John Jordan taught. He said that most of the water gets throw out of the wood cells when you get thin. You can reduce the moisture level even further by blowing compressed air through it. Then the bowl goes into a yard waste paper bag (double thickness of paper). I leave the bowl in that bag for a day. Day 2 I switch to a dry bag and hang the wet paper bag on the clothes line. I keep doing that for at least a week, maybe more. Then I use random orbit sanders to sand. It never goes back on the lathe. I have a 20” disc sander that I use to flatten the bottom. I would bet I’ve done it that way for at least 100 bowls.

 

[Lou Jacobs]

I think @robo hippy can address this as he mostly turns wet and sands on the lathe at slow speed to account for the distortion. One solution I can imagine is to use mesh type sanding media that can be rinsed as it clogs. But when I turn natural edge bowls which are done green and all in one turning, I don’t usually have a problem with power sanding with regular sandpaper.

 

[Lyle Jamieson]

I recently started turning maple and chestnut when its green and wet. I find the turning to be very easy and the result, after drying, very interesting. I would like to know what people use for sanding the wood when green. I find it far more awkward to sand them after they are dry and can no longer be mounted on the lathe.

I always turn green. With my glue block chucking method I reduce the bottom to a couple inches diameter and wait a day for the surface to dry and then sand as usual on the lathe. It may have a little distortion already so keep the lathe speed slow to sand. Reverse it after sanding and finish the bottom. let it stand a while and sand the bottom off the lathe using my drill press with sanding disks and mandrel.

 

[robo hippy]

This did get mentioned at our club meeting last night. I have found it far easier to sand them when dry. I mount on an extended jaws Vicmark chuck. Since the sanding process does not put stresses on the chuck that turning does, this is sufficient. Oh, I use a recess. The form is oval, and most of the time, I can get a good enough of a grip on it so there are no worries about it coming off. You need speeds of about 10 to 15 rpm. My American Beauty goes that slow, thanks to Brent walking me through the process. He commented that I should check the motor to make sure it does not overheat. Funny thing, it runs cooler when I am sanding than it does when I am turning. I do make my lathes work when I turn.... My 3520A would go down to about 10 rpm or so before it would turn off. With the B model, the lathe would turn off at 50 rpm. I think, with the C model, it is closer to 15 or so rpm. At those speeds, you can keep the power sander on the wood, even in most difficult conditions/warpings. I did make an articulated arm for supporting my hand/arm when sanding. Nice thing about it is that I can spin the bowl by hand since all the "work" of holding the angle drill is taken care of by the support arm.

View: https://www.youtube.com/watch?v=dnhdZh2Ens8


I guess I could sand without it, but that is too much work. I will never sand without it ever again.

robo hippy

 

[Doug Freeman]

I turn a lot of wet bowls and hf’s, 99.9% with a tenon. No matter how thin I turn it, it does in a double thickness thick kraft paper bag and into the house on a wire rack so drying conditions are consistent year around (whole house humidifier in winter). Tape bag closed with painters tape, weigh, write date and wt on tape, reweigh a few days and its dry. No bag chhanges and I have bags that have been through a few dozen turnings.

I remount dry work. It doesn’t take much to hold the work while cabinet scraping or sanding so I turn the tenon down and blend to the curve, which needs touched up with cab scraper and sanding. The lathe is generally off while sanding, rotating the spindle by hand, sometimes locking the spindle if an area needs significant work - just depends. I’ve tried sanding with a fixed sander and holding the work, didn’t work for me.

I add finish and finish the finish, then reverse, remove the tenon/shape the bottom, sign and then use parfix 3408, a water clue ca glue to finish. The bottom is always just a clear finish, while the piece could have dye and darker finish etc, but can always see the original wood on the bottom.

 

[hockenbery]

I would like to know what people use for sanding the wood when green. I find it far more awkward to sand them after they are dry and can no longer be mounted on the lathe.

I sand off the lathe after the bowls or hollow-forms have dried 3-4 days.
Sanding begins with a good tool finish.
I use a Mikita right angle variable speed drill with 3” Velcro pads. If needed I spot sand with 180. Then 220 and 320.
I try to keep the disc edge working in the grain direction.
Then a coat of Waterlox let dry over night sand with a folded sheet of 400 working in the grain direction.
Then repeated coats of Waterlox with grey scotchbrite between coats.
Then the Beal buff if I want a bit more sheen.

I just sit in a chair in front of a fan put an old towel on my lap rotate the piece with my left hand sand with the Mikita with the right hand.
Really easy unless the piece is really large or very small( go to 2” pads or some smaller things I have.

 

[Dave Landers]

Sometimes green wood will sand just fine, like as @Richard Coers said if you’ve spun enough water out, or if it’s just not that wet to begin with.
But usually if it’s too wet it’s going to just gum up the sandpaper. So you have to wait for it to dry at least some.
You can finish the bottom and sand in your lap (etc). Or leave the tenon/recess and hold it on the lathe. If it hasn’t warped too much you may get away with spinning the lathe slowly. Or just use the lathe as a holder and turn it by hand.

 

[Darryn Achall]

I'm of the school that lets the green wood dry after final turning. I then sand with a random orbit car polisher. It will hold 2" or 3" pads. I sometimes finish with a light sanding along the grain by hand if needed. Once I practiced up to the point where I can start with 180 or higher grit off of the tools, sanding isn't such a chore.

 

[Steve Doerr]

I turn a lot of bowls and hollow forms from green wood. I turn to final thickness and sand after I have completed the turning. I have found that regular 2" and 3" Mirka Gold clogs completely too quickly to be an effective abrasive. Instead, I use the Mirka Abranet. It does still clog but can be blown with my air gun. After I sand it and turn the tenon off, I then submerge it in DNA for 24 hours. After that I put it out of the DNA and let the surface evaporate dry and them put it in a brown paper bag and seal it. I weigh it daily (grams) and record it. Once it is losing less than 3% of its weight daily, I consider it dry and take it out of the paper bag. Sometimes I will then lightly re-sand the surface with the Mirka Gold. At this point if will dip it in my blend of oils for about 45 minutes and then dry it with blue shop towels and let it cure for 4 0r 5 days before I Beall Buff.

 

[Steve Tiedman]

A great book about the green wood turning design and process.
Turning Green Wood (revised edition), by Michael O'Donnell. Amazon link-

https://a.co/d/3w7xyZ5

 

[Donna Banfield]

I turn my green wood bowls relatively thin. I use the method John Jordan taught. He said that most of the water gets throw out of the wood cells when you get thin. You can reduce the moisture level even further by blowing compressed air through it. Then the bowl goes into a yard waste paper bag (double thickness of paper). I leave the bowl in that bag for a day. Day 2 I switch to a dry bag and hang the wet paper bag on the clothes line. I keep doing that for at least a week, maybe more. Then I use random orbit sanders to sand. It never goes back on the lathe. I have a 20” disc sander that I use to flatten the bottom. I would bet I’ve done it that way for at least 100 bowls.

I turn green to final thinness most of the time and do exactly everything that Richard discusses. The only difference is I put it back on the lathe simply to hold the piece. I use a Grex random orbital sander, and move the piece by hand. I can usually begin my sanding with 180 grit.