SS 3 1/2 Pound 5/8 Keyless Chuck

[nuhobby]

(the powpro is capable I guess).

Agreed. Last week I was roughing out a pretty squarish hard blank on the lathe, caught my chisel pretty strongly, and the PowerPro had a 'pause' in lieu of a belt-slip or a "throw the chisel at me".

[keakap]

Good news indeed! So the shaft was 'round', not hex or triple or other multi-faceted genre.

Sorry. I completely missed that part of your query.
Yes to round. These bits are the standard ShopSmith brad points (std circa late 80's, that is), all pure round shafts of varying diameters, all sized to fit the SS chuck of similar "circa", i.e. 1/2".
Funny, the brad bits I use most- 1" and 7/8 for wood screws- used to look big in the old SS chuck.

[Mike907]

Here is a picture of the chuck with the knurled ring removed. No through hole, just a dimple for the set screw. The set screw in my chuck takes a 3mm allen wrench.

Mike
[ATTACH]21582[/ATTACH]

[JPG]

Is it accurate to say the purpose of the knurled ring is to provide a firm gripping surface for a second hand when tightening and loosening the bits?

Also, is there a hole in the inside end of the bit 'cavity' to allow driving the tapered arbor adapter from the chuck since there is no 'drift' hole?

[Mike907]

No through hole. Maybe someone with experience with Jacobs tapers knows how to separate the chuck and arbor without damaging anything.

Mike

[JPG]

No through hole. Maybe someone with experience with Jacobs tapers knows how to separate the chuck and arbor without damaging anything.

Mike

A hole in the bottom of the chuck cavity or wedges between the arbor and the chuck body when a shoulder is on the arbor.

No hole means wedges are needed. I see a very small distance between the chuck and a shoulder on the arbor.

[pieceseeker]

Recieved my keyless chuck a few weeks ago, just haven't done anything with it yet.
The arbor is simply a taper fit, just like the lower ball joint attachment to a lower control arm on an automobile. It becomes wedged on with a small amount of force and separation can become difficult with out some means to force it apart.

[ATTACH]21590[/ATTACH]

The arbor on my keyless chuck came off with a little twisting and pulling by hand. I initially used a 1/4 drift pin and small hammer to drive the two apart, but it didn't take much of a hit to remove. The more force that I used to push and twist back on, the more difficult it was to remove. It is a precision fit.


As you can see, the arbor has a hole thru it, and the bottom end is threaded. Obviously, a long threaded bolt can be used to "press" the chuck off of the arbor. The bolt and the threads on the bolt will have to be long enough to pass thru the arbor and bottom out on the inside of the chuck.

[ATTACH]21591[/ATTACH]

The question now is, what size and pitch is the thread?

[ATTACH]21592[/ATTACH]

In my stash of taps here at home, I've concluded that the size of the threaded hole is either 5/16 or 8m. I have 2 5/16 taps, one 18 and one 24 pitch. Only the 18 pitch will screw in, but only 1 to 2 threads.

The 8m x 1.25 will screw in the farthest, but still only going about 3 to 4 threads before stopping.

I'll have to take the arbor in to work, where I have a wider range of metric taps and also SAE and metric thread gages. Will report back when I find the correct size and length of bolt required to use as a press.

FYI
[ATTACH]21593[/ATTACH]

Obviously, holding the chuck body while rotating the upper ring will require turning the whole headstock drive gear at the same time. (unless you completely remove the chuck and arbor from the headstock first)

[reible]

Recieved my keyless chuck a few weeks ago, just haven't done anything with it yet.
The arbor is simply a taper fit, just like the lower ball joint attachment to a lower control arm on an automobile. It becomes wedged on with a small amount of force and separation can become difficult with out some means to force it apart.

[ATTACH]21590[/ATTACH]

The arbor on my keyless chuck came off with a little twisting and pulling by hand. I initially used a 1/4 drift pin and small hammer to drive the two apart, but it didn't take much of a hit to remove. The more force that I used to push and twist back on, the more difficult it was to remove. It is a precision fit.


As you can see, the arbor has a hole thru it, and the bottom end is threaded. Obviously, a long threaded bolt can be used to "press" the chuck off of the arbor. The bolt and the threads on the bolt will have to be long enough to pass thru the arbor and bottom out on the inside of the chuck.

[ATTACH]21591[/ATTACH]

The question now is, what size and pitch is the thread?

[ATTACH]21592[/ATTACH]

In my stash of taps here at home, I've concluded that the size of the threaded hole is either 5/16 or 8m. I have 2 5/16 taps, one 18 and one 24 pitch. Only the 18 pitch will screw in, but only 1 to 2 threads.

The 8m x 1.25 will screw in the farthest, but still only going about 3 to 4 threads before stopping.

I'll have to take the arbor in to work, where I have a wider range of metric taps and also SAE and metric thread gages. Will report back when I find the correct size and length of bolt required to use as a press.

FYI
[ATTACH]21593[/ATTACH]

Obviously, holding the chuck body while rotating the upper ring will require turning the whole headstock drive gear at the same time. (unless you completely remove the chuck and arbor from the headstock first)

My bet would be the 5/16-18, a common thread on shopsmith equipment. You could test this with a common set screw off the shopsmith.....

The powerpro shaft is very easy to turn so it becomes very easy to turn the shaft while holding the chuck stationary I would guess. Like wise it will have no holding power of it's own so when tightening expect to be holding the adapter ring to tighten. Yea very different experience with the powerpro.

Ed

[pieceseeker]

The setsrew from the arbor does indeed fit the internal thread on the arbor, so just a matter of getting the right length bolt and threaded part to use as a puller.

It's becoming painfully obvious to me that I may have defective taps!

[JPG]

The setsrew from the arbor does indeed fit the internal thread on the arbor, so just a matter of getting the right length bolt and threaded part to use as a puller.

It's becoming painfully obvious to me that I may have defective taps!

Not necessarily so!

A 'new' tap will 'bind' in a threaded hole made with a worn tap or that has been in use or plated or . . . . That arbor is hardened besides.

Taps(or dies) are not a practical thread gauge.