I'm still not clear how the drawbar could've extracted the nose of the toolholder, and be jammed to the end of the thread. If it jammed, it would've stopped before the collet completely separated.
Unless... unless the drawbar TWISTED the part in two... but how was it assembled? If it was swaged together, that couldn't happen.
One thing in your favor, though. You could _try_ any one of the several suggestions without wrecking anything, then resort to the drill if you must.
snipped-for-privacy@aol.com fired this volley in news: snipped-for-privacy@4ax.com:
I found no _complete_ schematics, only an A-sized piece of any that were included. That's as useless as having not included it at all.
Because you don't know the difference between a wiring diagram and a schematic, and cannot read a schematic, you were unable to determine what was missing and what was not.
Even the wiring diagrams are incomplete in most instances. Included, but truncated. Apparently, you can't read those, either.
I never said schematics would help with mechanical issues. You drew that conclusion yourself. I suggested only mechanical solutions, none of which required a manual. YOU suggested that no manual should EVER be required for ANY repair on a Bridgeport. That's as stupid as the rest of your mindless drivvel.
So in short you being wrong now means you were right.
You were the one going on and on about wire schematics where the OP is clearly about a mechanical issue.
Again you are wrong, that was someone else's post not mine. I NEVER said or implied any such thing.
So how you planning on twisting this one so your being wrong will become your being right?
You related to Cliff?
You have our positions reversed. You are the one going on about missing schematics where the OP is clearly mechanical. I provided links to FREE resources that clearly address the OP issue yet you continue to bitch, whine and moan about wire schematics.
Classic problem. No, disassembling the head or spindle will NOT easily get you to where you can get it apart. That is the last resort.
First, do you know whether the thread has seized up, or did the collet just pull apart? If the latter, I'd first suggest trying to jam the collet back onto the dangling part in the spindle. If you can get it to partially mash together, and the thread is normally loose, you should be able to unscrew the drawbar in a jiffy. If the thread has seized, then you do have a problem. Is this a 1J or 2J machine? On the 1J (step pulley) the top of the drawbar is almost accessible, on the 2J is is buried WAY down in the varispeed.
If a 1J, here's the procedure, assuming a standard hand-operated drawbar. Remove two bolts and take the motor off. It weighs at least
75 Lbs. Disengage feed worm for the power quill feed (little crank on upper left side of head.) Remove 3 nuts below belt housing, and you can then lift the belt housing straight up and off the spindle spline. Be careful to not bend spindle. The top of the drawbar should be pretty well exposed at this point. Be sure to not get metal shavings into the bearings when sawing.
The procedure is pretty similar on the 2J, but you have to unload the springs on the motor pulley and do some other stuff to get the varispeed belt off.
Nope, won't work. There is a "skirt" on the top of most quills. if the machine has been torn apart at some time in the past, the skirt might be missing, otherwise it almost certainly is there. The quill bore in the castong has a larger diameter near the top, and this skirt wraps around the quill and fits into that larger bore. The skirt is made of about .030" sheet steel, and held to the top of the quill by two 6-32 screws, as I recall. No way to get the quill to go down without removing the skirt, and you'll mangle the skirt if you push it down farther than the stop ring normally allows it to travel.
Does this drawbar setup still have the pushout ring on it? (Not all machines ever had those.) If the drawbar would have just lifted straight out of the spindle with no collet there (before this incident) then there is no pushout ring. This ring allows the drawbar to push the collet out when the drawbar is unscrewed. If there is no pushout ring, then one other way to do this is to drop the SPINDLE - NOT the quill. I don't recommend this procedure, just saying it is possible. Remove the setscrew on the back of the quill that keeps the spindle nose ring in place. Unscrew the spindle nose ring. The spindle may or may not just drop out at this point, don't leave it unguarded while you put the ring somewhere, expect it could drop without warning. Given a LOT of room, the spindle can be dropped out the bottom of the quill. You may have to tilt the head to get enough room, the 2J spindle is pretty long.
The problem with this is that nose ring sets bearing preload, and has to go back EXACTLY where it had been before. Cleanliness inside the quill is also very important.
If the pushout ring was on the spindle, you'd need to get the varidrive housing off there anyway to remove it, or the spindle can't drop through. Or, maybe, this ring is accessible when the quill is ALL the way up. Hmmm, now that I think of it, it almost HAS to be accessible from on top of the varidrive, or the varidrive couldn't be removed, as the internal-toothed spline that drives the spindle is part of it.
Anyway, if the remains of the collet can be unscrewed from the drawbar, it will make this a whole lot easier!
snipped-for-privacy@aol.com fired this volley in news: snipped-for-privacy@4ax.com:
Wasn't wrong. Parts of schematics aren't "schematics".
Nope... I offered a couple of mechanical solutions. YOU went on and on about what I responded to Iggy's offer about the manuals. My comment had nothing to do about the problem, only the manuals themselves.
You never paid any attention to what anyone said, and never had the skill to realize you were wrong. Ignorance is fixable, your stupidity can't be cured, son.
My understanding of this CLASSIC Bridgeport disaster is that the cause was the collet cross-threaded, due to wear probably on the drawbar's threads. Does he have a power drawbar unit? I doubt this would happen when manually wrenching the drawbar.
Yeah, I think that IS the scenario. The threaded insert isn't really put in that tight. Just a bore in the back of the collet, and the slug is dropped in and the collet peened over a bit.
I don't think you will find ANY R-8 collets that aren't made like this.
I forgot about the skirt. You need to remove the top of the head to remove the skirt, and once you've done that you can probably cut the head off the drawbar without removing the quill.
The preload is controlled by spacers between the inner and outer races of the bearing pair at the nose, not by the threaded nose ring. The nose ring should be snug -- the torque is not very critical. But overtightening the setscrew that locks the ring will distort the quill enough that it will bind in the housing in the up position.
I've just looked at all my R8 collets and they all appear to be one piece, no insert. They are all of Taiwanese or Chinese origin I suspect. Looking at the drawing of an R8 collet in my BP manual it appears to show an insert threaded into the back of the collet but the drawing isn't that clear.
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