just received my new Supernova 2 and have been in the shop fiddlin' with it. Let me say here that I've been getting by with a modified Buck chuck. This is a metal lathe chuck with 6 scrolling jaws. For those interested, the jaws were cut on an EDM machine where I work to form the jaws for tenons. The thing is a behemoth compared to the Supernova and it's worked really well til I managed to bust off a jaw.
Okay, way off topic. The standard jaws with the new chuck are 50mm with a dovetail on both sides (expansion and contraction). There is a lot of attention paid to the expansion mode in the instructions, but zero mention is made of using the jaws with a tenon. What the...?
Am I okay with the standard supplied jaws to use with a tenon? I'm turning up to 12.5 inch bowls, about 5-6" deep.
Thanks in advance for any help you all can provide.
>You sure are. Just cut your tenon so the jaws are almost closed when tightened. If you have the cash pick up a set of the new 75mm bowl jaws. I have a set on my super nova and love them.
>...pick up a set of Oneway #3 Talon jaws. Their serrated jaws have a hold far superior to smooth jaws. Yes, they are interchangable with the Nova chucks...you only have to remove the roll-pin from one of the jaws (its the travel limiter for the Oneway chucks).
>the latest version of the 75 mm jaws will have serrations just like the Powergrip jaws (and the Oneway), have thicker walls than both of them, and will take a slightly deeper tenon.
Both the old and new styles (the older being originally smooth inside) are just outsttading jaws. I have the Oneway jaws in sizes #1 pin through 3 and I also think they're very good, but if I were a new owner of a SuperNova 2 (oh, gee, I guess I am) I'd choose the 75mm Novas. Though as originally said, the #2 will probably work just fine.
For additional thought on this chuck and these jaws, one can read the review I did for More Woodturning, located at the link below.
>Turners can disagree till they turn blue about chucks, which is a little like the Mac vs. Windows debates in some circles...
Here's my $.03 ...
Serrated jaws are better for some work, but not so good for other tasks. The Oneway jaws are better for holding square stock, and for contracting onto tenons that are a little too large. However, it is simply painful trying to accurately re-chuck a piece with serrated jaws. I find that for any pieces I intend to re-chuck, reverse, and manipulate a number of times, the smooth dovetail jaws are infinately better.
I'd use the larger, serrated jaws for rough turning, and months later would probably reverse the bowl between cenbters, true up the foot, and use the smooth jaws, especially if I planned to re-mount it at some time.
Also, there is not much info in my Supernova and Supernova2 booklets on how the tenon should be shaped (in fact, I got exactly the same booklet with each, so I have not seen a newer, revised S-N2 booklet, if one exists). The 50mm standard jaws have a dovetail profile at the tips only, which is rounded over somewhat on the inside.
Thus, to make a tenon that fits best, make a cylinder first, then cut a small dovetail at the base of the tenon, if the tenon is taller than about 1/4". I also have the 100mm (smooth) dovetail jaws, and they have a 15 degree dovetail all the way from tip to base, so a different tenon profile is called for. In expanding into a recess with the 50 mm jaws, the same is true -- if you cut a recess with a simple, deep dovetail, the hold will be very weak, as it will only contact at the base of the jaws, The recess needs to be a cylinder with a dovetail at the base only (that is, deeper into the wood) if the depth exceeds the depth of the dovetail profile (~ 3/16").
>Thanks everyone for the advice. It was very helpful. I played with the new chuck this wknd and am pleased with its performance. The 50mm jaws are a little small for the very heavy hickory I've been turning, so I just ordered the 75mm ones.
