Soft jaws for Vicmarc 120

[Larry Copas]

I’ve been hollowing coffee scoops by putting them into a jam chuck. I hold the scoop in place by a friction fit or hot melt glue. Hot melt is slow and requires clean up. Friction fit is slow because the scoop has to be a perfect fit. The jam chuck is only good for one size. The first pictures shows the jam chuck process.

No more, I made soft jaws to fit my Vicmarc 120 chuck. As made it will hold scoops from 2 – 4” diameter. I set the perfect circle diameter to 3” as that is the size of most of my scoops. It will also work for some of my other weird projects. In the last picture I’m using a reject scoop to check how it fits in the chuck and how tight it holds. It appears to work well.

The idea for the soft jaws has been rattling around in my head for a few months now. I came across Alan Stratton's website As Wood Turns
where he detailed the process of making soft jaws and went his route.

 

[Mark Hepburn]

Are the jaws made from UHMW or HDPE or something else?

 

[Larry Copas]

The base that screws to the chuck is 1/2" baltic birch and the actual jaws are black gum.


I was thinking about using HDPE or better yet Delrin but it is expensive and the coefficient of friction is very low so it might not be the best jaw material.

 

[Mark Hepburn]

Nice!

 

[Don Wattenhofer]

Here are a couple of examples of soft jaws I have made. The first one is first turned as a one piece mounted with a dovetail tenon then the 4 pieces are cut apart drilled as shown and reattached using longer machine screws. the contour can be changed by installing the wood worm screw and turning to the required contour.

This one is simpler to make and only requires the 4 saw kerfs and a hose clamp ( the tape is there to keep the tail of the clamp from flying out and is held in the chuck only with the dovetail tenon.

 

[David Stranz]

I have 3D printed several sets of soft jaws using 95D (durometer) TPU (thermoplastic polyurethane). I have also printed cup-shaped inserts from TPU to hold between normal jaws and for the tailstock to hold the ends of French-style rolling pins for refinishing after they have been parted off. The cups fit snugly on the ends of the pins and allow them to be held without damage for final sanding.

You can find ready to print models on Thingiverse. Search for "lathe soft jaws". Some designs are actual jaws like the ones described above, others are soft caps which fit over metal jaws.

 

[Dave Potts]

Perfect timing, Larry, Don, and others. I did some eccentric chucking recently, using just two jaws and the "spring action" of a wood disc to hold my stock. I was able to get the job done, but not ideal.

I'll be going the built-up jaw route on my next attempt. Thanks.

 

[Larry Copas]

Interesting and useful method, thanks for posting.

 

[Bill Alston]

I made a jig to accurately drill the four segments for the mounting holes of my chuck. It’s the only important part really as the rest of the “Jaws” are turned to shape once mounted. The jig is secured in a vice on my drill press. The small block marked “18” allows the jig to be accurately moved in the vice for the second set of holes in each segment. The 18mm offset suits Record Power, Sorby and Nova Chucks. I just cut the segments in my mitre saw.





I also reground a drill bit to drill and recess the screws in one operation.

Edit: This is the underside of the Jig and the step drill I ground. Why is the jig a funny colour? It’s made from one of my old Bowling Balls that cracked. It was an expensive ball when I bought it so I wanted to make the most of it after I made a bowl from it.

 

[Webb Willmott]

Do you have a NOVA chuck? Nylon ones from Amazon that can be customized.

 

[Bill Alston]

Yes I’ve seen those. Sorby and Nova ones are Red, and Record Power ones are Green! Wood is still cheaper though.

 

[Bill Alston]

If you want wood coloured plastic it seems you have to pay more!

 

[john lucas]

I built this for my chuck to give memory possibilities. The screws come out and can be moved to other locations. I can also add taller screws or put larger dowels over the screws

 

[John K Jordan]

I use the Nova soft jaws at times which register nicely on Nova chucks, made to be cut to fit the work.

And make jaws for special tasks. This one is made ONLY to hold chicken-sized wood eggs to reverse and finish turn the "holding" end. Made from soft cedar, fingers cut for flexibility, and with a threaded insert to screw onto the lathe spindle and made from Dogwood for strength. Eliminates the chuck completely.




The hose clamp could be hazardous to the distracted.

The size range is limited, though to the flexibility of the cedar. I think a variation of some shown with soft wood on a hard backing could be useful and save on making some jam chucks for small work.

For those looking for plastic materials, the recycling place near us often has materials for cheap. I once bought some big sheets of HDPE that were maybe 4-9' before the company cut out some smaller circles then tossed the rest. Got a sheet of the fire-retardant HDPE too. It's a different color but not much different in function. Both machine very well on either wood or metal machines and would make great soft jaws. Anyone nearby who could use some come visit.

JKJ

 

[Ricc Havens]

The idea for the soft jaws has been rattling around in my head for a few months now. I came across Alan Stratton's website As Wood Turns
where he detailed the process of making soft jaws and went his route.

View attachment 79031View attachment 79032View attachment 79033View attachment 79034

Cool idea!!

On a side note - Alan Stratton used to post weekly videos on YT. But he hasn't posted anything in months! anyone know how he's doing healthwise or if he just migrated to a different hobby?

 

[robo hippy]

I am still seeking some sort of soft jaw chuck solution for the boxes I am making. I am more into shallower ones, like 2 to 3 inches, mostly because if you go deeper, you need hollowing tools. I do like the hose clamp idea around some flexible jaws or plastic of some sort. I do need a "flat" to seat the tenon of the box on so it runs pretty true. I have considered longer screws for some cole jaws I have so they will grab higher. I do have a couple sets of extended cylinder jaws for my Easy Chuck, which get a fairly good grip on my boxes, and have a flat for the tenon to sit on. Still looking for the "perfect" solution....

robo hippy

 

[Bill Alston]

You can do quite a lot with Cole Jaws if you’re prepared to make a few custom parts. These are too large for things like boxes, but you get the idea.