Dumb question on R8 (i think) spindle

I purposely took out the pin in my PM-25MV. It was a set screw. The machine functions the same without the pin as it did with the pin.
 
Shootymacshootface said:
By what means do you keep the spindle stationary while you tighten the drawbar? Or, do you have a power drawbar?
Click to expand...

I know you weren’t asking me, but I use a spindle wrench. I don’t have a power drawbar.

image.jpg

That socket is a 10mm square drain plug (female) socket which fits on the top of my drawbar.
 
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I am now passed the question of set screw or not. I can tell it doesn't make a massive difference either way. I do need to figure out what on earth is going on with this taper. I charged my boroscope and will check tonight. I also verified the ring on the bottom comes off easily so I can pull the entire spindle if needs be. I believe it can now be driven out from the top after the spindle nut is released.
 
Is it just me,
or does the collet stick-out look very different between with draw-bar (from post 38):
1610028930987.png

and no draw-bar (from post 50):
1610029026480.png

Was that the same R8 collet?
Of course, one also has a tool in it and the other does not.
Is that the proper collet for the tool? (say both 3/8")

I'm suspicious of it being a Morse taper spindle.
Do you have any MT-2 or MT-3 arbors to try?

-brino
 
brino said:
Is it just me,
or does the collet stick-out look very different between with draw-bar (from post 38):
View attachment 350261

and no draw-bar (from post 50):
View attachment 350264

Was that the same R8 collet?
Of course, one also has a tool in it and the other does not.
Is that the proper collet for the tool? (say both 3/8")

I'm suspicious of it being a Morse taper spindle.
Do you have any MT-2 or MT-3 arbors to try?

-brino
Click to expand...
The second picture is my mill.
 
I think you might be onto something.
The spindle noses do look different.
Maybe it is an MT3.
 
What about using an inside bore gauge at about the same height of the spindle where it seats, and comparing that to the diameter of the collet? That might suggest a couple of things: First, if it's even possible for the R8 collet to seat any deeper. Second, if there is a taper or a bushing-style stop.

Just a thought.

Regards,
Terry
 
brino said:
I'm suspicious of it being a Morse taper spindle.
Do you have any MT-2 or MT-3 arbors to try?
Jim F said:
I think you might be onto something.
The spindle noses do look different.
Maybe it is an MT3.
Click to expand...
Click to expand...
OP's spindle has a set screw in the side of the spindle. If it was an MT taper, it wouldn't have that set screw, would it?

Tom
 
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