Question re: green turned wood, drying and sanding sealer/finish

[Tom Hansen]

I have a green turned vessel I turned to finished 1/8" thickness. I don't have much experience with finishing green wood and realize it's going to move a bit. Should I wait to let it dry before putting any sealer or finish on it? I've sanded it down to 400 and it's still attached to about a 1/2" tenon so I can put it back on the lathe and spin it in case I have a need to.

I'd like to seal it up, sand the sealer and start finishing with danish oil or osmo but not sure if that will lock in the moisture and screw me in the long haul.

Thoughts?

 

[Mike Brazeau]

I have made a few small things from fresh apple wood and sanded to say 220 then applied Watco Danish oil immediately. It slows down the drying process nicely. I just bring them in the house. After a couple of weeks it will be dry and you can rub with some synthetic material or 0000 and wax and buff. Works very well.

 

[hockenbery]

what did you make. .
leaving the tenon on will increase the chance of cracking. The tenon will not dry with the rest of the piece taking several weeks vs several days for an 1/8” walled vessel.

Some people apply finished like watco right away. I have done that but just not a step I do anymore.

I turn hollow forms and Natural edge bowls. I finish all the turning and only and areas that I will not be able to sand off the lathe. Usually just areas around a foot. Abranet works well on green wood but sanding dries the wood an intesses the chance of cracking.

I do almost all the sanding off the lathe after the pieces have dried. 3-4 days.

my procedure is to usually rinse the piece in the sink and towel dry. This gets the end grain wet.
I then put it in a cardboard box ( paper bag will work well too) Close the top.
Next day half open the box or bag (easy with a box leave one flap.
Next day open the top
Then put it on a shelf for a day
Then sand it and begin the application coats of finish.

at an 1/8” the piece will dry in 3 days.

 

[Richard Coers]

Most finishes won't stick to wet wood, or if they do, they'll blush since their is moisture under it. Definitely don't use any film finishes and absolutely don't use anything lacquer based.

 

[Tom Hansen]

It's about an 8" hollow form, maybe 5" width. I had a big tenon to turn it and parted that down to about 1/2" width and back about another 1/2". So basically just a small dowel type shape sticking out the bottom of it that allows me to remount. It's finish sanded as much as it can be and honestly I can't see a reason not to part it off if I'm just going to hand sand.

Good idea on the sink rinse.

 

[hockenbery]

parted that down to about 1/2" width and back about another 1/2". So basically just a small dowel type shape sticking out the bottom of it that allows me to remount.

This sounds like a good idea unlit you put pressure on the form and it spins around the tenon leaving a 1/2” hole in the bottom.

if your bottom is close to 1/8” thickness that tenon can easily pull out through the endgrain. Good luck with that.

One of my learning experiences with a thin endgrain HF was blowing it off with too much air pressure and making a hole in the endgrain area.

 

[Tom Hansen]

ouch haha. i have so many stupid failures like that just trying new things and learning the hard way. My latest one was buffing a day after last coat of spray on poly... sigh

Anyway, the vessel has been cut off, washed and put in a bag. I'll post a pic once done. Thanks all for the input.

 

[robo hippy]

A tenon that thick will add stress as the wood dries, and we all know stress in wood is relieved by cracking. A 1/8 inch tenon wouldn't be as bad. For pieces that I leave a tenon on, I soak the tenon in finish to slow the drying way down in the place of most stress. Personally, after sanding the outside and inside to final grit, I would reverse chuck it and turn off the tenon. Then all that is left to do is sand out where the tenon was removed. I would probably still put finish on the bottom of the bowl. Bowls always seem to be a bit thicker in the transition areas.

robo hippy

 

[hockenbery]

Bowls always seem to be a bit thicker in the transition areas.

.

In hemispherical bowls I like to the wall to be getting a thinner in the transition area and even a little thinner in the bottom to compensate for the foot. This gives a more pleasing appearance and a better feel when the thickest part of the wall is at the rim.

The importance of using calipers here really shows in the wall. A lot of times students want to rush through when they near the bottom and leave it thicker out of fear rather than use calipers to confidently cut it thinner. Thicker bottom make the bowl look clunky and it doesn’t feel good in the hand when the extra weight is in the bottom.

 

[robo hippy]

I have taken to leaving a small mini ogee at the foot of my bowls rather than the standard curve/arc from the foot to the rim. This does help keep the transition area at a more even thickness and reduces the uneven stress of thick/thin.

robo hippy

 

[Glenn Lefley]

I have taken to leaving a small mini ogee at the foot of my bowls rather than the standard curve/arc from the foot to the rim. This does help keep the transition area at a more even thickness and reduces the uneven stress of thick/thin.

robo hippy

Can you post a picture of what you mean please?

 

[Dave Hulett]

perhaps I'm the contraian here but if you've got it down to 1/8" get the finish on now. When enough coats are done, get the tenon off and finish the bottom, and your done. I turn lots of green wood and my experience is that I start a piece early enough in the day to turn it to final form the same day. The key is uniformity in thickness. if things dry at the same rate movement is minimized. Once down to final thickness and still on the lathe, I usually put a hair dryer on it for 10-15 minutes on both the inside and outside, then after it cools, do a final sanding, put on at least the first finish coat. All that in the same day. If for some reason I can't do that in one day, I wrap it with shrink wrap over night and get right to it the next morning. I've had some movement and occaionally minor cracks but nothing that ruins a piece.

 

[Leo Van Der Loo]

A 1/8" bowl/HF would be nearly dry by the time you have it turned and sanded, reverse it and remove the tenon now, before it splits, especially the bottom that has to shrink, bad place to have one part dry quickly and the other part much slower, being endgrain it does split easily, you can always glue a tenon on it if that is required.

 

[robo hippy]

Glen, I never figured out how to take the pictures, let alone post them. So, think instead of a smooth curve all the way from the foot to the rim, you do a little cove right at the foot of the bowl. I guess that maybe it is a 1/4 inch radius or so. I try to make it so that the firm pad from Vince, with the 1/4 round profile on the edge, fits right into that cove for easy sanding.

robo hippy

 

[Tom Hansen]

this vessel is birch burl. It's been in a bag now for a few days after parting off. It's kept it's shape nicely and is drying fine but the differences in the hardness of the burl has left all kinds of wavy surfaces all over. There is a quilted spot that has dried and shrank in ridges. It's not what I expected but kind of cool. I'll let it go for another handful of days and handsand it. Very curious if it turns out neat or horrible... Rustic either way. Beautiful piece of wood too.