Hi All,
Along with my G3 chuck I purchased a 1x8tpi adapter, type D. I have a Rikon 70-220VSR lathe. The thread adapter fits on my lather fine, but it doesnt appear to be fitting the chuck correctly.
The chuck comes with a grub screw and the instructions state the screw should be installed if the lathe is going to be run in reverse. The thread adapter has a valley past the threads for that grub screw to hold onto without messing up the threads.
My adapter does not screw down far enough so if I did install the grub screw it would mess up the threads. I have not yet installed the grub screw.
Without the screw in place, the chuck does wiggle loose when in use. I'm making a tool handle to accept the Hosaluk inserts. I turned a 16" long blank using a spur drive center and a live center in the tailstock. I created a round tenon for the G3 jaws to hold onto. When I mounted the blank into the chuck so that I could drill out the end to accept the insert I discovered it wouldnt spin round....it was out of round.
I had originally assumed I didnt mount between centers straight, and thus my tenon was parallel to the stock?? Possible??
I slid the tailstock back up against the blank assuming this would center it, and began running the lathe to see if it would spin round and within a few seconds I could feel a vibration. I move the tailstock off the blank and sure enough the chuck was no longer fully seated on the thread adapter.
I'm convinced I did something wrong, but cant figure out what that was. I think I have 2 issues....a mismatched thread adapter, and user error.
Thoughts? Below are pictures of the thread adapter seated into the chuck. You can see threads in the grub screw hole and the flange of the threaded insert is not in contact with the chuck. I did check the inside of the chuck and the insert is indeed bottomed out and cant be threaded any further.
Thank you, George
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