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bowl sanding help

2.9K views 11 replies 7 participants last post by  bigblockyeti  
#1 · (Edited by Moderator)
awhile ago i turned a live edge cherry bowl. it was turned green and dried in a bag with shavings.
no cracks or anything.
but, i turned it to final thickness.
it's now slightly warped and i had cut off the spigot so no easy way to remount it on the lathe and it wouldn't spin true anyway.

any tips for sanding the bowl at this point? it's pretty rough and needs a lot of work.

i've been looking at the 2-3" mandrel things but they all get bad reviews and seem to break easily.

ideas?

thanks
 
#4 ·
Ben, I've been a member at Lumberjocks for 11 days now, and finally decided to jump in instead of lurk. I hate to say it, but you don't need a lot of elbow grease to get your bowl sanded, and truing it up can be a piece of cake if you think about what you need to do.. I'm pretty bad at trying to relate how to do something, but I'm going to try.
Getting it trued up is nothing short of making a thick jamb chuck the size of the inside diameter of your bowl. I would use 2 pieces of 3/4" MDF to get the thickness. If you have a chuck, attach a tenon to this jamb chuck. Turn it to fit the bottom contour of the bowl. If your bowl is deep, add another thickness of MDF. Use that non skid sheet that is used in drawers in the bottom between the MDF and bowl.
Turn something that will go onto your live center that will not leave marks on the bowl bottom.It doesn't need to be bigger than 1"od. Lock the tailstock and adjust it until you think you can re-turn the bowl without it coming off the lathe. Sand until you think you're done, remove it from the lathe, and sand the small spot that was touching the bowl bottom.

If you want to sand the inside, do this first. Attach a glue block on the bottom and turn a tenon after the glue sets. . Mount it in your chuck, sand, turn or whatever you choose to do, and then go about the steps above for the outside. You don't need to make anything for your live center because you'll have the tenon and dimple from the live center to center and tension your bowl. Turn until you have the nub that most people turn to, then remove it from the lathe, cut off the nub, and sand the small spot on the bottom to completion.
I've invented several tools that makes remounting a completely finished form a no brainer. In a couple weeks I'll post pictures if you are interested. ............ Jerry (in Tucson)

. .

...
 
#5 ·

I use 2" back up pads
http://vinceswoodnwonders.com/back-up-pads/

2" inner face pads
http://vinceswoodnwonders.com/firm-and-soft-innerface-pads/

2 3/8" ceramic disc

http://vinceswoodnwonders.com/ceramic-discs-2/

Some folks like to get their disc sanding gear from
www.woodworkingshop.com

I buy sanding supplies from both of those vendors.

When turning wet wood to final thickness try to sand ASAP, might be while bowl still on the lathe or even week or two later. Once lose ability to remount a bowl on lathe pretty tough to sand or further turn both inside and outside of bowl.

You can certainly try procedures Jerry outlines they work. Or if have enough wood on base take a forstner bit and drill base deep enough to get back on your chuck.
 
#7 ·
Thanks guys!
I was hoping to hold the bowl in my hands and sand it on the drill press with the 2" pads.
I think I'll that first and if it doesn't work I'll try to remount it on the lathe.
Getting it centered would be the hardest part, then I'd have to do a lot more turning and risk breaking it.
But yea, next time I'll sand it green!
 
#8 ·
Ben, With green turning, I usually turn and sand the outside to finish, saturate it with Watco oil, which will stop it from drying out. Then turn the inside, down to about a 1/2 inch wall thickness, then I spritz it with just enough water while turning to keep it damp. It will start to dry when you start the sanding, and then oil the inside. A bit of dampness will still remain, but the oil will allow it to dry without drastic movement. I know this sounds kinda weird, but I turn green/wet wood like this all the time, and have never had a problem. Set the bowl aside for about a week for the oil to dry, buff it out, then put on a finish of choice.
 
#11 ·
Ben

You can power sand it with a drill and 2" or 3" pads. On making a bowl green bowl you always have to save the tennon or foot at the bottom.

The wood will always worp to some degree while drying. One way to help stabileize it is to keep the wall thickness equall to the size of the bowl. Example is a 12" bowl should have a wall thickness of 1" or a 6" bowl left for drying should be 1/2" and the bottom of the bowl should be about 1/8" thicker then the walls and no more to give it stilibility.

Good luck on your future turnings.

Arlin

PS - You can keep a stack of paper sacks on hand and wood shavings to put the bowl or other object in after turning and put the dates on it as well.
 
#12 ·
If you can get a really thick backer pad for a random orbit sander, that would allow the hook and loop or adhesive backed paper to conform to the contours of the bowl while the sander does the work. I have one thick pad (~ 5/8") for my Porter Cable 7335 which works pretty good. I also have one for my pneumatic 6" DA sander if I'm going to be sanding a lot for a while.