pipemakersforum.com

Hi guys,

I just spent a few hours on Autocad trying to design some jaws for my Teknatool Supernova chuck. Right now, with the jaws that i purchased for the chucks, I'm pretty much limited to chucking up briar blocks with the maximum of 52-53 mm width. I'm thinking of getting a machinist to make a new jaw for this chuck. Below are the pictures of what I have designed. Since I've only been making pipes for a while, I reckon that I would like to get some opinions on this design before I go ahead. Oh btw, with this design, I believe I will be able to chuck a block with appx. 64mm width, plus I have incorperated some threaded holes in the jaw for 'pin' inserts. I have all the necessary autocad drawings, if anyone wants to review them.

Do let me know what your opinions are...



Cheers,

Adry

I ... suspect... that you want a bit stronger of a joint between the plates and the jaw themselves. I would add a bit of material on the outside so you could weld a triangle of metal in there for support....

Sasquatch wrote:I ... suspect... that you want a bit stronger of a joint between the plates and the jaw themselves. I would add a bit of material on the outside so you could weld a triangle of metal in there for support....

Sorry sas, don't really get what you mean

I think the jaws will not be strong enough - I think they'll bend/flex because they have no support in the direction that they are being torqued. As you squeeze a briar block in there you'll just bend the bolts that the extended "jaw" part is bolted on with.

Sasquatch wrote:I think the jaws will not be strong enough - I think they'll bend/flex because they have no support in the direction that they are being torqued. As you squeeze a briar block in there you'll just bend the bolts that the extended "jaw" part is bolted on with.

good point... will do some redesigning i suppose

OK i had to redesign a little. This is where i'm at...

That second design looks a lot stronger. Make sure your machinist uses an alloy like 4140 that can be hardened and tempered. Plain old mild steel will eventually bend at the corners. Speaking of corners, be sure to leave a rounded fillet on the inside corners. A sharp inside corner in steel is a stress point where cracks can begin. NOT something you want to happen at 1200 rpm.