R.I.P. Friction Drive?

[Michael Mills]

It seems the Friction Drive has just about met its demise as far as I can tell.

At one time there were Jam Chucks and Friction Drives. Two completely different methods. Now it seems there is just a Jam Chuck (going by most post and almost every youtube video).
The pic (turningsartgroup) is what a Jam Chuck looked like when I started turning. You hold a bowl, box, or other item by turning a waste block with a very tight fit and you can finish the bottom without tailstock support.
I would call this a “chuck” as it is made to hold the item without tailstock support (scroll, Longsworth, Jacobs, donut, collet, etc).

The other pic (turnawood bowl) is what I had always heard called a Friction Drive (until a few years ago). The last I can recall in a video was by Bob Hamilton.

Given the "friction drive" it is now called a “chuck” even though it needs tailstock support does that mean we now have four prong, two prong, steb, and safety chucks?

If a Friction Drive is now called a Jam Chuck then what is the “original” Jam Chuck now called?

[John K Jordan]

I and others still like to use the term friction drive to differentiate. To me, a jam chuck is something turned to fit a piece, concave or convex, an extension of the age-old cup chuck or pin chuck. Perhaps to some the flat surface midway between concave and convex could considered in the same class of holding methods, but to me it doesn't make sense to describe it as a "chuck". Do these people talk about a "faceplate chuck"? (have they ever used a faceplate?)

When turning small bowls or platters I use a Glaser "screw chuck" on the top then turn a recess on the bottom for a scroll chuck. But what about the turner with no screw chuck? One of the three methods I like to show in demos is holding the flattened blank with friction between blank and the jaws of a chuck spread wide, pressed tightly with the tailstock. (I actually use a dovetail scraper ground at an angle to cut the recess but haven't updated my sketch yet.)

395164

The wood interface you show might provide a bit more friction but I've never had one slip pressed into the jaws only - I can't even budge it when I try. I don't use this method to turn the outside and bottom, but if I needed to I'd use the wood interface you showed with a bit of CA glue, or a face plate with some double-sided tape.

I can understand why someone might consider a piece "jammed" up against a flat as a "jam" chuck, but using the two terms consistently can help with the communication. Those who don't differentiate might be considered by some to be a touch unrefined. But there are worse things in life.

The trend towards smearing these definitions is new to me, perhaps since I rarely watch YouTube videos on woodturning. So much is so bad - seemed to me that everyone with a EasyWood roughing tool and a couple of weeks of practice started making junk videos. Here's an idea for you - maybe there's a need for a YouTube video explaining the difference, "Jam Chuck or Friction Drive??" by Michael Mills!

JKJ


It seems the Friction Drive has just about met its demise as far as I can tell.
At one time there were Jam Chucks and Friction Drives. Two completely different methods. Now it seems there is just a Jam Chuck (going by most post and almost every youtube video).
The pic (turningsartgroup) is what a Jam Chuck looked like when I started turning. You hold a bowl, box, or other item by turning a waste block with a very tight fit and you can finish the bottom without tailstock support.
I would call this a “chuck” as it is made to hold the item without tailstock support (scroll, Longsworth, Jacobs, donut, collet, etc).
The other pic (turnawood bowl) is what I had always heard called a Friction Drive (until a few years ago). The last I can recall in a video was by Bob Hamilton.
Given the "friction drive" it is now called a “chuck” even though it needs tailstock support does that mean we now have four prong, two prong, steb, and safety chucks?
If a Friction Drive is now called a Jam Chuck then what is the “original” Jam Chuck now called?

[Perry Hilbert Jr]

mention a cup chuck sometime.