R8 Arbor With Jacobs Taper

[kingmt01]

I have


It came with a R8 arbor with a Jacobs taper.

Does anyone know what size that taper would be?

I tried to put a j33 chuck on it but it is bigger then the arbor.



Those are the only two places it is touching on the very end.

 

[Bob Korves]

Measure the taper of the arbor at the small and large ends and the distance between those measurements and report back.

 

[RJSakowski]

Here is a chart of Jacobs Taper sizes from Wikipedia: https://en.wikipedia.org/wiki/Machine_taper

 

[middle.road]

That is looking awfully straight to me... A #3 which is common would have a ~.060" diff.
How long in the taper in your hand?
Lose the cool tools as the background, and shoot it against a straight edge and a contrasting background.

 

[kingmt01]

Big end is .618" small end is about .585" I don't have a good way of measuring taper. It is about 3/4" between those measurements.

 

[kingmt01]

.775" to the best I can measure is the length.

 

[middle.road]

Looks close to a #33...

 

[kingmt01]

That is what I was thinking. I suck at trig to figure out the size at .775" tho.

 

[kd4gij]

Are you sure that chuck doesn't have a JT3 taper?

 

[middle.road]

Even if we were to trig it out, there is still the fact that the bluing is messed up...

Any number on the chuck?