Bridgeport J Head Pulley Collet Align Screw Replace..?

Per Emilio, the new collet is what is having the issue, the old ones do not (?). Emilio would not likely be buying a cheap collet, but he said this BP is at his work, so it might be one they bought with poor quality control in production. I would first vet the collet before I would go to the trouble to replace the pin to accommodate it.
 
There are a total of three set screws.
A. The spindle nose set screw
b. jam nut lock set screw
c. dog point collet alignment set screw 3/32" protrusion.
Q: do I need to lower the spindle taper an inch more for better access to the alignment screw? I read that this can change the pre-load on the bearings?

Bob; I was using a brand new USA Hardinge R8 collet. The collet was working fine w/o binding, then one day, it got stuck.
The head on the alignment pin is mushroomed., not smooth and the Hardinge R8 looks fine., not worn, so that may be part of the problem.
The machinist at my job was telling me that he recently replaced the collet screw and that it is only one screw. I tried to explain that there should be a jam nut set screw behind it, but he got angry and said NO! it's only one! I said, OK, No problem. One screw. That's the other problem. :)

I'll just use the worn R8 collets and when I buy my own BP mill, It will be well maintained.
 
Don't waste your time replacing the screw, just remove it . A lot of people remove it , just becomes a pain dealing with it. Mine was screwed up several years ago and I just removed it and never replaced it. I've never had a problem since. It also makes loading a collect or R8 shank much easier.
Its only purpose that I could find was to stop the collect or R8 from spinning while installing or removing. If your collect or R8 is spinning, you may have a thread problem which should be addressed.
 
My Bridgeport does not have it. There is just a hole there. I don't have any issues. It seems like a video I watched,the guy said he wondered why the collett locating pin is there?
My 2 cents.
 
I had a collet that would not go into my spindle without binding and luckily I thought to check the register diameter on the collet before doing anything with the key or keyway... it was almost 0.001" bigger than my other holders and collets. After some polishing in my lathe and getting it to the same size as my others it fit fine!

Just something to check,
Ted
 
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