BP disaster: snapped r8 collet?

Awl--
Ok, y'all know how you tighten the r8 collet/em in. Here's what happened:
Upon tightening sed r8/tool, the thread of the r8 popped out, the r8 collet
body/em fell out, and the drawbar and the r8 thread/nut are now just spinning in the machine, with nothing to lock it so the drawbar/threaded pc can be removed!! So the hex draw bar/r8 nut just spins freely!
Cheap chinese collet. I never knew the threaded part was separate! Now, upon looking, in some r8's they are indeed one piece, in others the threaded insert is held by two set screws, and in others, the collet is just peened over a threaded insert.
This did not happen to me, but to my buddy across town, and I'm being commissioned to deal with this, as I can climb up and about the machine, and he can't.
So what's the prognosis here? One guy said to remove some plate or another up top, and we might be able to hacksaw the drawbar off below the hex, letting the draw bar/r8 nut fall down. True? Sumpn else?
giganto pita. tia.
--

Mr. PV'd

Mae West (yer fav Congressman) to the Gangster (yer fav Lobbyist):
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Proctologically Violated wrote:

2700 rpm air impact, long screwdriver, tape, ?
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On Jan 21, 10:09 am, "Proctologically Violated"

I would be looking to find a way to hold that threaded insert. I think I would find a block of wood or plastic that will fit up into the spindle and capture that bugger with some friction. Use the knee crank to make the table hold it up inside. Then spin the top with an impact wrench. Wrecking the drawbar would be my last resort.
Later,
Charlie
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How does the broken collet look? Can you insert it back into the quill, and push on it as well as on the drawbar, so that it would not turn while you unscrew the drawbar?
Worst case, I think, you can drill the drawbar out from top.
i

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On Jan 21, 10:28 am, Ignoramus15648 <ignoramus15...@NOSPAM. 15648.invalid> wrote:> Due to extreme spam originating from Google Groups, and their inattention

Your choice.
Later,
Charlie
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On Wed, 21 Jan 2009 10:31:54 -0800 (PST), Charlie Gary

Hey, it's a huge problem that has to be addressed - Google takes all sorts of very effctive measures to stop E-mail Spam from reaching our Inboxes - but they are the most pernicious source on Usenet.
I've complained. If you, and everyone else who is affected by it complain, perhaps they'll fix it.
Even something as simple as a Captcha and all users start with a probationary account with an initial posting limit would work - and an easy way to report the spam that gets that probationary account immediately cut off.
Apply the same heuristics they use on E-mail, and the account would get bounced on the second or third spam post.
Slowing the spew to a trickle is just as effective, the spammers don't want to spend fifteen minutes setting up an account per piece of spam payload delivered, it ruins the economies of it.
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Without the Google Groups filters, I see a lot of spam (shoebuydirectchinawholesale.com or whatever). With the filter, almost never any spams. Hence why I do it. It is not really political in any sense. I do try to unblock any specific posters who use google groups if I notice.
I

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"Proctologically Violated" wrote:

If the thread portion wasn't actually bottomed out on the threads of the drawbar it may not be stuck. If you can reach up and grab it with some long nose pliers you might be able to free it. Otherwise just pulling up the drawbar and cutting it off should do since drawbars aren't expensive.
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On Wed, 21 Jan 2009 13:09:19 -0500, "Proctologically Violated"

That would work if you remove enough of the drive portion of the head. Is this a step pulley or variable speed head? Step pulley is a lot easier.
I think in either case it would be easier to pull the entire quill/spindle ass'y and cut the drawbar on the bench. Remove the quill feed shaft and, if my memory is right, the quill will drop out. The worst part is messing with the counterbalance spring, especially getting it reset after reinstallation. Use a block of wood between the spindle nose and table to control the removal and replacement of the quill.
I think Iggy has manual scans, which should have blowups of the head.
--
Ned Simmons

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wrote:

Variable speed head.
We dread dis-assembly. But you are talking about just removing the crank handle/spring, right, and this will drop the quill? Yeah, I've screwed that spring up myself on another BP!
I think Iggy's idea might be good, esp. if perhaps we can shove the broken r8 back up with some good strong epoxy on it. 2-part epoxies can have incredible shear strength, depending on the formulation AND on thickness -- you need between .010 and .030 on the radius, for a good set.
Epoxies are used preferentially to press fitting bearings, in some cases!
The wood/knee ideas and impact wrench sound good too, and I think some combination of all would be feasible -- mebbe shove some wood up through the re-attached collet for add'l friction on the nut.
We are in fact getting a cheapie impact wrench, which can come in handy for other stuff.
But, my buddy, who is perty experienced with BPs (but not as a mechanic per se) is hemming and hawing, dudn't think this will work, and may not pick up the air impact wrench. What a pita....
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Sounds like a great way to epoxy the collet to the inside of the quill. Am I missing anything?
Hold the bottom of the broken collet in a vise, press on top of the drawbar with a wood clamp or something, and unscrew the drawbar with a wrench, it just might work.

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Proctologically Violated wrote:

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!
Jon
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wrote:

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.
--
Ned Simmons

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volley in

now
is
over
being

below
PV, did the nut hit the dead end of the thread on the drawbar, or _just_ pull out of the toolholder? My inclination is to think it _couldn't_ have pulled out, and also have jammed on the screw.
If it's not jammed on the drawbar thread, then a toothed tool (like a small hole saw) might be jammed up against its lower surface, and provide enough friction to unscrew it.
Even a small screwdriver or punch might be brought into play.
LLoyd
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On Jan 21, 1:59pm, "Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote:

Yes. Jam a long thin screwdriver between the threaded part and the quill ID. IIRC the lengthwise groove cuts across that part, do you have others like it to examine?
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message

Yup might as well get a broken off screwdriver tip stuck in there too while he's at it...
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Well... YOU might honk on the drawbar until it broke the tool. I'd try to finger-loosen it <G>.
LLoyd
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message

I was thinking maybe he should try using a stick welder...
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Well, lean that head over to horizontal so you can get a peek at it.
Can you reach in and drill a couple holes in the insert? Likely cheese steel.
Okay, now make a pin spanner to hold that insert.
Remove.
HTH,
Wes
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Oh, left out you may need to cut some tapered wood wedges to drive about the insert to stablize it so you can drill into it.
Wes -- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller
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