No Collet pin in my step pulley Bridgeport

Janderso

Jeff Anderson
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Mar 26, 2018
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I found a YouTube video on replacing it. I have a hole up there.
It looks pretty straight forward.
Now for a dumb question.
How do you tighten the collet? It has a tendency to spin so I grab a shop towel and tighten up best I can. Yes the small end mills will spin so I tighten it up a bit more. There has to be a better way.
Thanks
 
A lot of people take the set screw out for easier alignment. As for the setting of pin. Drop the spindle to allow access to screw area. You don’t have to pull spindle completely out. Correct parts should be a through set scre then your collet alignment screw. Put a good collet in spindle. Run dog point set screw down touch collet and back off 1/4 turn. Slide collet make sure it slips in and out. Then lock through set screw to other. Which locks the first. Push spindle back up and spindle cap. Don’t crank on cap screws will distort quill. Done deal. If Bridgeport.
 
Many people don’t have the alignment pin, it’s purpose is only for keeping the collet from spinning while it is being installed or removed and maybe some repeatability on tool changes.It is not designed to hold the collet from spinning under cutting conditions, that’s the tapers job. If your endmills are slipping or pulling out under load, it maybe to heavy a cut, a dull endmill, or a worn out collet. Just some food for thought.
 
I would suggest that you run a new tap thru all the Colette's you may have some garbage or corrosion on the threads and then lubricate . I do this to mine on a regular basis. The Colette should not spin while tightening . Also check your draw bar threads.
 
Brand new set from a McMaster-Carr.
New end mills, cut depth, maybe but I try to be very aware of the cut each pass.
It just seems like when I insert the collet in the spindl, it draws up but the spindle turns anything beyond finger tight.
 
Spun a collet on the set screw and it broched a notch in the collet slot, like to have never got it out. Took out the pin and have not had any trouble in years.
 
Janderso it's not really clear. Is the collet spinning when you are trying to tighten the collet? OR Are the endmills or I guess collet spinning while your cutting. If tightening collets and their spinning while tightening either your drawbar threads are boogered up or rolled over or the threads on collets could use a chase. You said collets are new so they should be good but t least run a tap to see.
If your collet is spinning or endmills spinning in collet you have a lot more going on than the collet pin missing. Blue a collet and see how it mates to spindle. Could have burns or a chip in there.
 
Ok, I’ll check it out. The collet is not slipping, the small end mills will slip at times. I’ll take out the draw bar and mate it to a collet to check for any dubious conditions.
Thank you for the help
 
Brand new set from a McMaster-Carr.
New end mills, cut depth, maybe but I try to be very aware of the cut each pass.
It just seems like when I insert the collet in the spindl, it draws up but the spindle turns anything beyond finger tight.


You should have a brake to hold the spindle while tightening the collet.
 
A month later.... I replaced the draw bar. Got it from H & W. I wanted to rule out any issues with a simple replacement. The original was bent. I haven't used it yet. Regarding the spindle brake, mine does not work. Adjustment? What would be the typical cause of it not working?
 
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