Dumb question on R8 (i think) spindle

[MrWhoopee]

The set-screw you have circled in your picture is too high to be they key (hold a collet next to the spindle). It is usually under the collar at the bottom of the spindle. I wouldn't be spending any time trying to replace it. When I owned my shop we would just remove them when they got damaged (which always happened sooner or later). I've been fighting a damaged key in my Kent mill since I got it. This discussion has motivated me to go out and remove it.

Under no circumstances would I consider pulling the spindle to replace the key.

 

[Shootymacshootface]

My G0730 has no spindle brake

By what means do you keep the spindle stationary while you tighten the drawbar? Or, do you have a power drawbar?

 

[aliva]

Mine sheared off a few years ago and I never replaced it. It's quicker when inserting a collet I don't have to line up the collet to the pin. I understand many people never replace them for this reason. By the way I have a power drawbar.

 

[kd4gij]

Take the ring off the bottom of the mill and the setscrew for the key is there where I circled

 

[Tim9]

On my Asian RF45 clone, I have a splined wrench which I purchased from Grizzly to hold the spindle when I tighten/ loosen the drawbar.
FWIW, My mill has a set screw which acts as the “ keyway “ and it’s been sheared off too. I wouldn’t worry about it. Not an issue.

Spindle Spline Wrench

Manufactured from steel, this new spline wrench was designed especially for holding the spindle spline on many Chinese made round column, square column, and other like-sized mill/drill machines and the smaller X3 sized machines. This wrench has a 28mm spline on one end for the larger machines...

www.grizzly.com

 

[Tim9]

By the way, if the mill is new for you... Take care not to leave the wrench there and then turn on the machine. The sound is deafening and will scare the hell out of you. It made me jump back.

 

[Mitch Alsup]

By what means do you keep the spindle stationary while you tighten the drawbar? Or, do you have a power drawbar?

There is enough friction so I can take the wrench and just give it a sharp pull.
Drawbarrs do not have to be "that" tight--they just have to register the taper so the tool is concentric with the spindle.

On the other hand, when I tighten up the ER-40 collet holder in the spindle, I use a collet wrench in one hand and my other hand on the pulley to get enough pull to cinch up the collet.

 

[r-mm]

My spindle mystery deepens some.

The machine came with only a JT33 Chuck. I presumed its shank to be R8 but noted it was not in great shape. No big deal, it can always be replaced I thought. However on closer inspection I don't believe this to be an R8 shank at all. I frankly do not know what it is, does anyone here?

I now believe this non R8 shank tore up the spindle.

This is my first R8 machine so I do not know what an R8 collet should look or feel like when inserted. A friend with showed me his R8 collets inserting flush and practically falling out when not held. Mine R8 collets insert with resistance and stay put when not held, they need a little knocking from above to release. Even even when tightened with the drawbar they protrude about 1/4in as pictured.

Looking for guidance here please!

Thanks.

 

[Jim F]

That is NOT an R8 arbor.
JT33 is the Jacobs taper.

 

[r-mm]

Any idea what the arbor is? (and is it not called a shank?)

Does the fit of my R8 collets look okay?