PDA

View Full Version : Arrrrrrrrrrrrr, Bridgeport



Tim Clarke
02-06-2010, 08:54 PM
In a moment of stupidity, I snapped off the key in the BP spindle. I had a slitting saw in a stub mandrel. Mine tends to be self tightening. I finished the job, and removed the assembly, only to remember I hadn't loosened the nut first, so I could remove the blade. So, I put it back in the spindle, and HAND tightened the drawbar. Put the wrench on the nut and gave it a big yank, while holding the spindle brake. Yup, SNAP went the key.

So, I made a nice spanner wrench, removed the nut at the bottom of the quill, after removing the locking screw. Took a ball end allen wrench and removed the locking screw, then the key screw. Looked at and said, self looks like a 1/4-28, I have some, this should be no problem. I decided to verify it's really a fractional thread, rather than metric. As far as I can tell, it's a 1/4-32. ARRRRRRRRRR. And other expleteives.

None of my catalogs list any 1/4-32 screws. Taps, and dies, yes. I do believe that if it's really the only way, I can build one from scratch, with a slot rather than the hex socket.

Anybody know a good source of BP small parts? I hate to pay $20.00 shipping and handling on a 50 cent part.

Thanks, TC

KINGWELD
02-06-2010, 09:02 PM
Try this. [machinerypartsdepot.com]. Great people to deal with. Jim:)

Toolguy
02-06-2010, 09:05 PM
I have always taken the key out of my spindles for 20 years. If the tool is over torqued and turns in the spindle, there is only some scuffing, as opposed to deep scars if you gouge the collet/toolholder and/or snap off the key. I have taken some very heavy cuts with the CNC mill (R8 spindle) and not spun the toolholder. It makes manual toolchanges way easier doing dozens or hundreds a day not having to find that key every time. Try running without for a while. You will probably never put it back in.

lakeside53
02-06-2010, 09:23 PM
Yep.. no keys in any of mine... never problem tightening either.

gda
02-06-2010, 11:46 PM
Out of the 20 or so bridgeports I have seen, none of them had the key. Mine in the garage does not either.

Arcane
02-06-2010, 11:48 PM
Yep.. no keys in any of mine... never problem tightening either.
Same here...I removed mine early on...had to :o

Carld
02-06-2010, 11:51 PM
Why in the world would you want to replace the broken key? It is a pain in the ass most the time and the loss of it is the best thing that can happen.

toolmaker76
02-07-2010, 08:34 AM
Over the years I have worked with Bridgies that had keys and also had keys missing. One shop I was at purposely removed them I think. It is a quicker easier setup without I think.

The only real consequence is if your collet has some damaged threads, it will be tough to install; you learn pretty quick to take it out and run a tap through it to clean the threads up (trust me, its worth the time) but once that is done, you are good to go again.

Try it for a bit without the key- you may decide to leave it out!