Supernova (1) key once again - help, please

[Lars Hansen]

The first model Supernova (the one with the text on the face of the chuck as seen on att. pic.) had a terrible chuck key.
I've just started a rescue mission, trying to convert a lump of dirt and rust into a working chuck. Both chuck body and scroll now look rather nice, so now I face the serious problem.
Both Teknatool US and NZ have run out of spare parts.
I'm looking for jaw slide and a key.
If anyone here has one of these chucks and would be so nice, I'd love to get a little info and a few measurements.

TIA,
Your's, Lars

 

[Lance Mirrer]

Sent PM

 

[John K Jordan]

I mostly use the newer SN2 but have a drawer full of the original SN. What info and measurements do you need? Do you plan to machine replacement parts?

I bought a few used from club members (a couple needed extensive rework.)

The chuck key on those is the worst. I understand why they made them like that but you can make them easier to use (for most things) with a bit of epoxy or spot welding.

 

[Lars Hansen]

@JKJ: Thanks, will get back with a photo, a few numbers and an explanation.

An aftermarket chuck key is ordered and on it's way.
One issue down, one to go.

 

[Lars Hansen]

These are the measurements taken from the chuck body.
I've attached a pathetic excuse for a drawing.

Metric:
T: 4.0
G: 8.0
W: 21.6
H: 6.8

Inches:
T: 0.15
G: 0.3
W: 0.48
H: 0.27

@ JKJ:
If you would measure the corresponding dimensions of a Supernova 1 jaw slide, that would be a great help.
I still hope to find an original set in good shape.
That would complete the revival of the chuck.
Lars

 

[rkriet]

This is a little off topic, but does anyone know where I can get a chuck key for the Nova G3 chuck? It’s the first chuck I ever bought and I still use it once in a while, but now I’ve lost the key.

 

[John K Jordan]

@ JKJ:
If you would measure the corresponding dimensions of a Supernova 1 jaw slide, that would be a great help.

Sure, but might be a few days. Occupied with medical things now.

If you are planning to fabricate one, you prob know this but remember the “threads” that mesh with the spiral scroll gear plate are different for each of the four slides. Otherwise the dimensions on the slides should be the same.

This is a little off topic, but does anyone know where I can get a chuck key for the Nova G3 chuck? It’s the first chuck I ever bought and I still use it once in a while, but now I’ve lost the key.

Amazon.com

No experience with this. I gave all my G3 chucks to a friend.

 

[Lars Hansen]

@ Ron: The model is still sold, so any Teknatool Nova dealer should be able to help you.
Have a look here:

Find a Dealer - NOVA, a Teknatool Brand

Nova Teknatool International is a global manufacturing exporter since 1980, with facilities in NZ, China and the USA.

www.teknatool.com

 

[John K Jordan]

If you would measure the corresponding dimensions of a Supernova 1 jaw slide, that would be a great help.

Ok, I took one apart today. With Starrett digital calipers, multiple measurements. There is some variation in the measured dimensions.

G: 0.300-0.303"
T: 0.157-0.158" from the machined cut on the top of the chuck
H: 0.262-0.263" measured at open end of the slot only
W: 0.498-0.500" measured at open end of the slot only

 

[Lars Hansen]

@ JKJ: Thanks SO much. Late here, will dive into the numbers first thing tomorrow.

 

[Lars Hansen]

Numbers in hand, it was much easier to tell turning collegues what I was looking for. My local tool dealer searched nooks a crannies and found a set of jaw slides from a chinese Nova ripoff.
Now I'm filing away to make them fit the chuck.
Importantly, the slides seem to fit the scroll perfectly.
Close to completing another step towards a working chuck.

 

[John K Jordan]

Now I'm filing away to make them fit the chuck.

If they need considerable filing, do you know anyone with a milling machine? That can remove and shape metal with extreme precision (if set up properly).

Long time ago I had to do considerable filing to make a couple of used chucks work.
I bought two SN1 chucks used from a fellow club member, then found they wouldn’t open or close easily, or in one case, at all! The chuck body of both were actually warped at the thinnest places near the slides.

I decided the guy must have used WAY too much force when tightening the chucks. I suspect he used a “cheater” bar on the chuck key, since no one but the Hulk could apply that much force by hand. I spent considerable time with files and other tools until they both worked perfectly. At least they were very cheap. The moral is “don’t abuse your chucks!” If a turner needs more force than can be applied with the hand, they are doing something else wrong.

I've been using those chucks since. I never told him they were warped but I'm sure he knew. Caveat emptor.

JKJ

 

[John Whitley]

I suspect he used a “cheater” bar on the chuck key, since no one but the Hulk could apply that much force by hand

Richard Raffan recently posted a video surveying the chucks and jaws he uses, and this exact point came up (start about the 5:00 mark). His Vicmarc key's plastic T-handle broke, revealing an L-shaped key. He remade it with a wood handle only modestly longer than the original – and was sure to caution viewers that it's easy to overtighten and damage the chuck that way.

 

[Lars Hansen]

After a bit of filing and unpacking my xmas gift to myself, the old chuck is ready for battle again.
Thanks for useful tips and comments.
Lars

 

[John K Jordan]

Richard Raffan recently posted a video surveying the chucks and jaws he uses, and this exact point came up ..[using cheater bar].. and was sure to caution viewers that it's easy to overtighten and damage the chuck that way.

Not only damage the chuck you can damage the wood too.

The way I far prefer to get the chuck tight so it won't loosen (and can't damage the chuck):

• Make SURE the tenon or recess is properly sized and shaped. (another entire topic)
• While holding the piece firmly in place (perhaps with the tailstock if appropriate) tighten in one "key hole" snugly, (with the hand only) but not tight.
• Rotate the chuck 180 deg while still supporting the piece firmly and tighten the second hole snugly.
• Then continue to rotate 180, tightening each time a little more firmly. I repeat this several times. There is never any need to use extreme force with the chuck key. I once heard a respected demonstrator say "tighten the chuck in all six places!"

This tightens the jaws EXTREMELY well without over-stressing either the chuck or the wood. Not once have I had a piece come out of the chuck. If a turner ever has a piece come out of a chuck, he/she is doing something wrong. (IMHO)

(And if concerned about precision as well as holding power, remember to clean the threads and the mating surfaces of both the chuck and the lathe spindle first. Check also for any burrs. And don't forget to check the tightness of the screws holding the chuck jaws.)

JKJ