What make and model is your lathe ?
They sell both direct threaded and insert chucks. I believe the more expensive grizzlys are vicmarc clones with inserts. But the chuck I got is direct threaded.The Grizzly chucks have inserts don't they ?
If I were you , I'd sell the Grizzly chuck and then by a Nova .Well, I tried to return my incorrect sized chuck to grizzly, but apparently with their return policy, I would only be getting about half what I payed back. (10% restocking fee, + shipping through a means of their choosing, and no refund on the shipping I initially payed)
So I'm thinking I'll just try to sell it on ebay, then get the nova chuck. I'll re-measure it a few more times, just to make sure I'm getting the correct size this time.
Another option I was thinking about though, do they make a spindle adapter? I saw one place had a 1 1/8 x 12 tpi to pretty much every common size, but it would run me $70, which just seems silly, considering I payed less for the lathe itself.
http://bestwoodtools.stores.yahoo.net/precspinad.html
Does anywhere else sell them?