Anyone else ever removed their R8 drive pin?

If a collet is going to spin due to aggressive cut wouldn't an end mill holder do the same?
 
I think the pin is only there to keep the collet or driver from turning in the spindle while you hold the brake and tighten the drawbar. Until the collet or driver become locked in the taper there is nothing to hold it from rotating unless you are holding it up into the taper. A clean taper and quality collets are the only way to avoid slippage.
 
That pin is simply a locating pin for the collet. It does not drive anything. It just keeps things in line. Most Bridgeports I have seen don't even have them anymore due to breakage.

"Billy G"
 
[If a collet is going to spin due to aggressive cut wouldn't an end mill holder do the same?/QUOTE]
Yes, but you can tighten up a end-mill holder a lot more than you can a collet without damaging it. So a end-mill holder should take a lot more force before spinning. I was taught in my tech school machining classes to use end-mill holders for heavy cuts. Collets are meant for lighter more precise cuts. What is a "lighter cut" ? Depends on your machine, material, DOC etc. For example: I've got a plain jane Bridgeport Series I ( 1HP) and R8 spindle. I have several coarse roughing end-mills (3/8 & 1/2) in end-mill holders for removing material quickly. I can hold them tighter in the end-mill holder than I can in a collet. Saves wear and tear on my good Lyndex collets and end-mills for when I get close to final dimension. I do have a few old R8 collets that I don't mind abusing if necessary. But either way I don't want anything to slip and score the inside of my spindle. When using the roughing end-mills in the holder I only push them as fast as the machine tells me (chatter, color of chip, etc). So in summary you can grip a end-mill tighter in the end-mill holder and tighter in the spindle.
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I didn't remove my key but I did shear it off and have not replaced it but have had no problems without it but I understand that there is a way to replace it without complete disassembly of the spindle. bill
 
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