Vicmarc VM120 Chuck question

[Dale Winburn]

I would like to make some custom Jaws for my VM120 chuck. Can anyone give me the radius for the grooves and of the screw hole pattern for the jaws, or point me in the right direction to find the info. This radius would be when the jaws are adjusted so the grooves would be in a perfect circle.

Thanks,
Dale

[Geoff Whaling]

Why not try contacting Vicmarc directly - http://www.vicmarc.com/default.asp?contentID=510

Shouldn't be to hard to measure if you already have a chuck and a set of verniers or dial calipers.

[Reed Gray]

My understanding for the making of the jaws, and they need a slight tenon on the bottoms, is that they machine a circle with the dove tail, then cut it into quarters. This is in part so that you make a tenon or recess slightly over size, and then when you grip, there should be a slight gap between the jaws. I have heard of using PVC, and cutting a slot in it, then using that inside the jaws. It will close down to pretty much a perfect circle.

What to you need these jaws to do?

robo hippy

[Dale Winburn]

My understanding for the making of the jaws, and they need a slight tenon on the bottoms, is that they machine a circle with the dove tail, then cut it into quarters. This is in part so that you make a tenon or recess slightly over size, and then when you grip, there should be a slight gap between the jaws. I have heard of using PVC, and cutting a slot in it, then using that inside the jaws. It will close down to pretty much a perfect circle.

What to you need these jaws to do?

robo hippy

Reed,

I have a 1" thick tough plastic sheet about 2' square, don't know what type it is, it's very tough but not brittle. I will turn the back of the jaws with the tenon that fits the recesses in the chuck and drill the screw holes using my metal lathe. I will then cut the resulting circle into quarters. I can then custom turn the face as needed.

Thanks,
Dale

[Reed Gray]

Delrin is one type of 'plastic' that is sturdy enough for machine work, and can hold detail pretty well, including cutting threads. I would think Corian would work too. Are you making some softer non-marring type jaws for a soft grip?

robo hippy

[Dale Winburn]

Delrin is one type of 'plastic' that is sturdy enough for machine work, and can hold detail pretty well, including cutting threads. I would think Corian would work too. Are you making some softer non-marring type jaws for a soft grip?

robo hippy

I picked up this plastic at a salvage yard, it machines well and yes, you're right, I plan to make non-marring jaws for expanding inside of lidded boxes, pencil boxes, etc.

Dale

[Jeffrey J Smith]

why reinvent the wheel - vicmark makes plastic jaws you can turn to any configuration you want - http://www.vicmarc.com/default.asp?contentID=587