- Joined
- Jan 27, 2005
- Messages
- 12,886
- Likes
- 5,169
- Location
- Dalworthington Gardens, TX
- Website
- pbase.com
Personally, I would not buy a chuck that didn't match the threads of my lathe. Spindle adaptors add manufacturing machining operations between your spindle, and the attachment point to your wood, as well as adding distance. All these things add to the possibility of changing concentricity, and exacerbating any vibration issues.
Adaptors, and inserts are not the same thing. Although my Stronghold chucks have inserts, this Record Power chuck is direct threaded. That's an advantage, in that it has fewer machining operations, and therefore less possibility of throwing off concentricity. You can test the concentricity of spindle, and chuck if you have a dial indicator and base. A couple thousandths runout at the chuck is good, and considered normal.......although, obviously, less is better.
It should be understood that a piece of wood will turn concentric to the spindle, not the chuck. This is not a problem for turning your work, but means that if there is any runout at the chuck, then remounting will have to be keyed specifically to the placement of the chuck jaws in exactly the same place as before.
-----odie-----
I suspect that Lawrence really meant "insert" rather than "adapter" compared to direct thread chucks. Inserts are high-precision parts whereas adapters are limited by the cumulative tolerance build-up of two times the spindle threads and registration face. All of my chucks except for one use inserts mostly because that's what is available. If you look at the number of different inserts that Oneway sells it becomes obvious why the great majority of chucks use insets. I can't tell the difference between my direct thread Vicmarc 120 chuck and the Vicmarc 120 that has an insert.
An adapter isn't a substitute for an insert ... it is used as a go-between the insert threads and the spindle threads. It would typically be used when temporarily using your chuck on a lathe with different threads than the lathe that you normally use. Unless you're a teacher or demonstrator you might not ever have a need for an adapter.
The importance of Odie's last paragraph might not be fully appreciated if you are new to turning, but its significance can't be overstated.