Paul39
20th June 2009, 12:17 PM
I got carried away replying to another post and removed the following.
It might be of help to someone.
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I start my bowls by hacking a more or less flat spot that will be the top and screwing the timber to the face plate. If it is small with a lot of contact with the faceplate, I just run the tailstock up against it and let friction drive the timber and the point of the live center keeps it in position.
i rough the outside of the bowl and make a place for the chuck to grab either inside or outside, but leave a definate mark for the center. I take it off the plate and mount the bottom on the chuck and again run the center against the timber.
Almost always the bowl will wobble a bit. I then hollow about 3/4 of the depth leaving a spigot up the center for the live center and the sides 2 or 3 times the finish thickness, depending on how dry the timber is. I then oil both sides with boiled linseed oil and wrap in several layers of news paper and let it sit for a week to three months depending if it is dry or wet.
When it is time to remount I have center references on both sides as well as the recess or base that the chuck griped. In addition to having the references, the center keeps things more secure while I am hollowing so I can be more agressive with less chance of getting a mouthfull of timber.
I find even the dry ones move around quite a bit while they are resting.
I remount with the bottom slightly loose in the chuck and gently tighten the point of center in the spigot, tighten the chuck and tail center, true the top of the rim and finish cut 1/3 to 1/2 down the outside.
Then I take the bowl off the chuck, put on the faceplate, top of bowl against faceplate, live center point into center mark of bottom. Finish cutting outside of bowl, make round where the chuck grips, clean out close to where the live center point is holding, sand and put on first coat of tung oil.
Then I take it off the lathe, mount the chuck, mount bowl in chuck, run dead center up to center hole in spigot and give the bowl a couple of spins by hand, If the hole is centered, tighten, if not cut the hole off and tighten in the new position.
I true the rim and hollow as much as I can with the center in, then back out the center, cut down spigot, finish cut the inside, sand and finish everything I can reach. I wet sand with 220 and tung oil, apply more tung oil with a small piece of cloth while running the lathe. I have a long stalk with a pad on the end that fits on the tailstock to gently press the bowl onto the chuck.
After an overnight dry, I wet sand with 400 and tung oil and then several coats more of tung oil rubbed with the bowl on the lathe.
When it is finished I dismount the bowl, tidy up any marks where the jaws gripped, gently slice off the reference hole / bump on the bottom with a sharp wood chisel, sand and finish with tung oil.
This is along proceedure, but I rotate several bowls and weed pots in process through the lathe, along with roughing out one or two new pieces each session.
I have 20 to 25 pieces in process, some I am waiting for more skill and / or equipment. I have a long piece that is not hollowed as I need a steady rest. The figure is so nice I don't want to ruin it.
It might be of help to someone.
------------------------------------------
I start my bowls by hacking a more or less flat spot that will be the top and screwing the timber to the face plate. If it is small with a lot of contact with the faceplate, I just run the tailstock up against it and let friction drive the timber and the point of the live center keeps it in position.
i rough the outside of the bowl and make a place for the chuck to grab either inside or outside, but leave a definate mark for the center. I take it off the plate and mount the bottom on the chuck and again run the center against the timber.
Almost always the bowl will wobble a bit. I then hollow about 3/4 of the depth leaving a spigot up the center for the live center and the sides 2 or 3 times the finish thickness, depending on how dry the timber is. I then oil both sides with boiled linseed oil and wrap in several layers of news paper and let it sit for a week to three months depending if it is dry or wet.
When it is time to remount I have center references on both sides as well as the recess or base that the chuck griped. In addition to having the references, the center keeps things more secure while I am hollowing so I can be more agressive with less chance of getting a mouthfull of timber.
I find even the dry ones move around quite a bit while they are resting.
I remount with the bottom slightly loose in the chuck and gently tighten the point of center in the spigot, tighten the chuck and tail center, true the top of the rim and finish cut 1/3 to 1/2 down the outside.
Then I take the bowl off the chuck, put on the faceplate, top of bowl against faceplate, live center point into center mark of bottom. Finish cutting outside of bowl, make round where the chuck grips, clean out close to where the live center point is holding, sand and put on first coat of tung oil.
Then I take it off the lathe, mount the chuck, mount bowl in chuck, run dead center up to center hole in spigot and give the bowl a couple of spins by hand, If the hole is centered, tighten, if not cut the hole off and tighten in the new position.
I true the rim and hollow as much as I can with the center in, then back out the center, cut down spigot, finish cut the inside, sand and finish everything I can reach. I wet sand with 220 and tung oil, apply more tung oil with a small piece of cloth while running the lathe. I have a long stalk with a pad on the end that fits on the tailstock to gently press the bowl onto the chuck.
After an overnight dry, I wet sand with 400 and tung oil and then several coats more of tung oil rubbed with the bowl on the lathe.
When it is finished I dismount the bowl, tidy up any marks where the jaws gripped, gently slice off the reference hole / bump on the bottom with a sharp wood chisel, sand and finish with tung oil.
This is along proceedure, but I rotate several bowls and weed pots in process through the lathe, along with roughing out one or two new pieces each session.
I have 20 to 25 pieces in process, some I am waiting for more skill and / or equipment. I have a long piece that is not hollowed as I need a steady rest. The figure is so nice I don't want to ruin it.