Lew Hartswick

01-31-2011, 07:42 PM

I'm trying to cut a couple threading indicator "gears" (a couple of the lathes

seem to have eaten a few teeth) (don't ask me how, I cant figure it

out either)

Since the gear has 40 teeth and that gizintas 360 so nice and even at

9 deg I thought the Spindex would be the easiest to use since it can

incerement in 1 deg steps. WELLLLL, I just finished the first experiment

and it seems to have picked up an error. By the time I got back to 0

the cutter did NOT hit the first 0 location by about an 1/8 of an inch

on a blank 3.15" dia.

Picture 1

http://i233.photobucket.com/albums/ee238/LewHartswick/DSCF0009.jpg

So the mandrel or the collet must have sliped but by looking at the

teeth there is no obvious discontinuity and going back over the

locations it is obvious that it is some gradual error. ie. checking at

90, 180, and 270 the error is gradualy increasing. Now the spindex

just can't pick up a gradual error it has to come back to 0 and be

the same place. So figure it must be the way I turn the wheel or be

related to that.

Next IDEA have a couple dividing heads as follows:

http://i233.photobucket.com/albums/ee238/LewHartswick/DSCF0010.jpg

http://i233.photobucket.com/albums/ee238/LewHartswick/DSCF0011.jpg

Problem is the Ellis has a 1 3/4 - 8 thread and a B & S 9 taper bore

the Japinese one has a 1 1/4 - 8 thread and some small taper bore

and the only 3 jaw chuck I have is 1 1/2 -8 thread and the mandrel

is 5/8 shaft.

Now two questions; 1 what is going on with the Spindex or

2 How can I hold the 5/8 shaft in either of the dividing heads?

Thanks.

...Lew...

seem to have eaten a few teeth) (don't ask me how, I cant figure it

out either)

Since the gear has 40 teeth and that gizintas 360 so nice and even at

9 deg I thought the Spindex would be the easiest to use since it can

incerement in 1 deg steps. WELLLLL, I just finished the first experiment

and it seems to have picked up an error. By the time I got back to 0

the cutter did NOT hit the first 0 location by about an 1/8 of an inch

on a blank 3.15" dia.

Picture 1

http://i233.photobucket.com/albums/ee238/LewHartswick/DSCF0009.jpg

So the mandrel or the collet must have sliped but by looking at the

teeth there is no obvious discontinuity and going back over the

locations it is obvious that it is some gradual error. ie. checking at

90, 180, and 270 the error is gradualy increasing. Now the spindex

just can't pick up a gradual error it has to come back to 0 and be

the same place. So figure it must be the way I turn the wheel or be

related to that.

Next IDEA have a couple dividing heads as follows:

http://i233.photobucket.com/albums/ee238/LewHartswick/DSCF0010.jpg

http://i233.photobucket.com/albums/ee238/LewHartswick/DSCF0011.jpg

Problem is the Ellis has a 1 3/4 - 8 thread and a B & S 9 taper bore

the Japinese one has a 1 1/4 - 8 thread and some small taper bore

and the only 3 jaw chuck I have is 1 1/2 -8 thread and the mandrel

is 5/8 shaft.

Now two questions; 1 what is going on with the Spindex or

2 How can I hold the 5/8 shaft in either of the dividing heads?

Thanks.

...Lew...