Here are some chucks and a live center that I have and use.
The simplest chuck is the screw chuck. It is made for creating the bottom (or back) of a bowl. A hole is drilled into the part of the wood blank that will be later hollowed out and then the blank is screwed onto the chuck. A spigot or foot is usually turned using this chuck so that the bowl can be turned around in an adjustable jaws chuck and then hollowed out. | |
The next most simple way of holding a bowl on a lathe is the face plate. Screws are put through holes into the wood. Later, the bowl is turned around and hollowed using an adjustable chuck. | |
Here is the adjustable chuck I use, the Vicmarc 3½" key operated.
The jaws adjust to clasp a foot or spigot turned into the bottom of the
bowl (one of the first things to do after roughing the sides and bottom.
The jaws can also dovetail into a recessed foot rather than clasp it
from the outside. Once held this way, the bowl is emptied using gouges
and, optionally, scrapers. I used to use a scraper to finish up because
it is very easy to control and I am a beginner. However, since Clead
Christiansen's beginning turning class helped me solve my once-disastrous
gouge technique, I no longer do so unless it is the only way to reach
into a closed (more hollow-form) bowl. The gouge always cuts the end
grain cleaner.
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Okay, so I got Vicmarc's bigger chuck, the 5" (same picture). I started increasing the size of the bowls I was turning when I got my Vicmarc lathe. Plus, I now tend to leave the Adjusta-Jaws (see below) installed on the smaller chuck, I no longer have to change chuck jaws as often since I leave this bigger chuck standard with the clutching jaws always in place. With a screw chuck, this chuck and the Vicmarc 3½" chuck with the Adjusta-Jaws, I am almost completely equipped not to have to change tooling when I turn bowls. I just wish I had a good vacuum chuck now for the bowls that the Adjusta-Jaws can't grasp. | |
The Vicmarc Adjusta-Jaws can replace the original clutching jaws in my adjustable chuck to permit removal of the spigot used to hold the piece while coring out the inside. That is, if no foot is desired. Or, the foot can be reshaped instead of removed to form a base for the bowl to rest on. Basically, this system is a way to hold the bowl bottom-out again after emptying the inside. Other methods include press-fitting the top lip of the bowl into a wooden face plate specially turned out for this purpose (time-consuming and annoying) or using a vacuum chuck (somewhat expensive and/or challenging to build). | |
The ONEWAY Manufacturing Live Centre mounted in the tailstock is much better equipment than the stock center that comes with most any lathe, even a spiffy one like my Vicmark live center. It has a full point and bull-nose cone both of which are accessories. The live center is built upon two ball bearings for longer life. |