Tuesday, May 4, 2010

Day 259: For Chris

A trio of Weedpots from Acacia Visco tonight.  The wood is still pretty green but I think it will hold up well.  These are intended to go back to Boyce Thompson in a month or so, just long enough to make sure they won't split.

They aren't hollowed, just a 1/2" hole down the center.  They're inteded for dried flowers or similar materials.

For Chris.  The basic process I use.

Small half log of Jacaranda.  Approx 7X7.  The log is split in half through the center.  The face you see is the split face and will be the top of the bowl.  There are a number of ways to start the turning, such as between centers or on a faceplate.  On this piece I chose to use a screw chuck or woodworm screw.  The center of the piece was found and a 3/8" diameter hole was drilled approx. 3/4" deep.

The screw center is held in the jaws of my chuck.  The holding strength is not from the threads themselves but from the contact of the wood against the flat face of the jaws.

Blank mounted for turning.  The tailstock is in place for safety.  The bottom of the bowl will be on the tailstock side, the top of the bowl is facing the chuck.

Turning started.  The outside of the bowl is being shaped.  Cuts are made from the bottom of the bowl up to the rim.  Cutting from the rim down will leave torn grain.

Outside shape finished.  A tenon has been formed on the bottom.  This tenon will be gripped in the chuck so I have access to the inside of the bowl.  Tenon size and shape are pretty critical.  The tenon is less than 1/4" deep and about 2" diameter.

The bowl has been reversed and the tenon gripped in the chuck.  Nothing is holding it on except for the tenon and the surface contact between the bottom of the bowl and the top of the jaws.

Turning the inside of the bowl.  This is done in stages, always working from the rim down to the bottom of the bowl.

Inside finish turned.  I would normally sand and finish the inside and the rim at this point.

Bowl reversed and mounted on my vacuum chuck.  A vacuum pump pulls a vacuum through the headstock and into the PVC "drum" between the lathe and the bowl.  The tailstock is in place to help center the bowl on the drum and for safety.

The vacuum supplies more than enough negative pressure to hold the piece in place for light finishing cuts and sanding provided the wood being used doesn't have open pores or voids.

Bottom of the bowl turned.  At this point I would normally sand and finish the bottom of the bowl.

Finished piece.  Elapsed time was approx. 15-20 minutes.  Sanding and finishing would easily double that time, as would a larger bowl.

1 comment:

  1. I like the step by step presentation. Some things that may be basic to yourself or other experienced turners can be a revelation to a newer turner such as myself. The highlight of my morning is my coffee and your blog. Keep it going Jason!