On 2008-05-03, Joseph Gwinn wrote:
In article ,
"DoN. Nichols" wrote:
On 2008-05-02, Joseph Gwinn wrote:
[ ... ]
Ahh. Yes. It will take a while, but I may scan my manual, which does
not appear to be copyrighted.
Hmm ... beware that you can't e-mail it to me. There is a limit
of 30K total size on incoming e-mail, to keep virus infections out of a
couple of small mailing lists which I host. No problem with my systems,
of course -- but I first turned on the limit when I got over 300 copies
of a new spam on the first day, and 200 more on the next day. I forget
what it was, but it was spreading like wildfire, and it took a long time
to clean out my mailbox enough so that I could read valid e-mail.
OK. I'll probably post it to the metalworking archive.
You mean to the dropbox http://www.metalworking.com? That
should do -- or perhaps to the archive of manuals which Iggy is building
up.
[ ... bed twist ... ]
Better with the near foot on the tailstock end and the back foot
on the headstock end bolted down, even if the other two are not. That
should resist the twist introduced by the drilling.
Well, if I do bolt it down, I'll probably do all four feet. But I'm
reluctant to bolt it down, because I may move it. Nor is a basement
slab all that thick and rigid, compared to the floor in an industrial
plant.
O.K. Mine is not bolted down -- but I don't see the kind of
chatter that you do. Perhaps it is because most of the industrial
service life of the machine was as a turret lathe, where most of the
motion was in the turret ram.
[ ... ]
The 5914 manual also speaks of bolting to the floor, but few people
actually do this I suspect.
Indeed -- unless forced by OSHA inspectors. :-) Now, if I were
doing lots of faceplate work, I would bolt it down just to be sure that
the lathe does not start walking around the shop with a bit of imbalance
on the faceplate. :-)
I'm still looking for a faceplate. One can buy a new faceplate plus L00
back from Bison for about $300, but the need is not immediate, and so
I've been watching eBay.
O.K. So was I -- until I found one at a flea market/picnic held
by the local metalworking club (which, BTW, is also where the dropbox
is. :-)
In looking at the 5418 manual, I see that it was also sold without
cabinet stand, for mounting on an owner-provided bench.
With a somewhat different headstock which allowed the belts to
run back to a rear-mounted motor instead of down into the pedestal.
Thus, the
adjusters had to be between cast iron stuff and the base (bench or
cabinet).
Yes -- but before that, it was common to adjust between the feet
and the cabinet (or table) with stacks of shims.
[ ... ]
Agreed. Check the tailstock end too -- because that is what
would flex when the torque is transmitted from the spindle to the
carriage. It would wind up the bed (a little, at least).
The tailstock now clamps pretty firmly to the bed. This is one of the
first things I cleaned and adjusted, mainly because it was easy and
could be done without the manual.
It was not the tailstock to the bed that I was thinking of. I
was assuming that it would be well clamped, and for turning it would not
make a difference anyway. But bed feet to stand and/or stand to floor
are where the wind-up could be controlled.
Ahh. Now it makes sense.
Good.
[ ... ]
http://books.google.com/books?id=Skd...lpg=RA8-PA36&d
q=gooseneck+tool+lathe&source=web&ots=edrQWKc6hu&s ig=QsKeq0Vn7zebOdjC5ydY
KtuqnkA&hl=en#PRA8-PA35,M1
Hmm ... I don't think that I'm going to bother cut-and-pasting
all three chunks of that URL. I know the tool anyway, and see them
occasionally on eBay auctions.
In the original posting, you should be able to just click on the URL,
even though it appears wrapped, because I provided start and end
delimiters ( ... ). In quoted postings, this won't work, and editing
is required.
Nope! *I* can't -- because I don't use a GUI-based newsreader.
I can click on the url and get at most a single line of it to paste to
a browser or another window with a command line.
People with GUI-based newsreaders (especially those built into
web browsers) can do so. Frankly, I am glad that I can't, because it
makes it more difficult to accidentally click on a malicious link.
[ ... ]
Perhaps this is why one commonly stated cause of
chattering is too-sharp tools. When one carefully blunts such a tool,
one puts a little bit of very negative rake right at the cutting edge.
How much backlash is there in your cross-feed leadscrew? The
self-feed can take the slack out of a worn leadscrew/nut pair. And you
want the cross-slide gibs to have a bit of drag, too.
I have the gibs adjusted so there is much drag, but the cross-slide
backlash is about 0.020", and the compound slide backlash is about
0.006".
O.K.
The compound slide backlash was ~0.055" when I got the lathe, and so I
replaced the screw and its bronze nut. What a difference it made. I
have no idea why it was so worn compared to the cross-slide; perhaps
someone replaced the cross-slide screw and nut.
Well ... my cross-slide had 0.070" backlash. But I know why.
The power feed was used for parting off workpieces after the turret does
most of the work of shaping them. So the carriage just sat there, the
compound was untouched, and the cross-slide cycled under power for every
part made.
The cross-slide wasn't too bad (after being cleaned and adjusted), so I
left it alone. At least for now.
O.K. But when you are experiencing chatter, you might also try
placing a finger where it can sense motion along the cross slide.
[ ... ]
Hmm ... another thing to check. While you have chatter, see
whether there is any relative motion between the headstock and the bed.
If it is not clamped down firmly enough, or if there are chips trapped
between the headstock and the bed, that could introduce enough give to
create problems.
Hmm. Offhand, I don't see any safe way to do this, as my hand would
need to be very close to the spinning chuck, or to various gears and the
like.
There is space where the outer ways stick out from under the
headstock (which is clamped to the inner ways) and you should be able to
check back along the near side far enough to be clear of the chuck.
Ahh. I see what you mean. One can get at the back of the lathe safely
enough. The problem is that I cannot then reach the handwheels to
advance the toolbit into the work. I'll have to cogitate on this.
Isn't there access above the quick-change gearbox? The gearbox
is bolted firmly to the bed, so you could sense motion between the top
of the gearbox and the front of the headstock.
[ ... ]
I doubt that the headstock was ever unbolted, at least not by the people
[ ... ]
Well ... you have the lathe in your basement I believe? Some
people disassemble the lathe to several heavy components and take each
down separately. If you didn't, perhaps someone else did previously.
It's possible, but I'm pretty sure that I am the first HSM owner of this
lathe, so this is probably its first basement gig. And my basement has
level entry, so no disassembly was needed.
O.K. That helps greatly.
The headstock is located on the bed ways by careful fitting of headstock
bottom to ways, plus a pair of steel dowel pins to prevent sliding.
O.K. Mine has one taper pin, not two dowel pins.
What I called dowels are in fact #6 taper pins, and they fix the
headstock to the bed way, preventing motion along the bed way.
O.K. That is as it should be.
There are in addition four pointed bolts that attach the bed to the cast
iron pedestal foot. I thing these studs are pointed for ease of manual
assembly in the factory.
Hmm ... I've not checked how my bed feet are attached.
[ ... ]
O.K. This produces fewer paths for swarf to get down into the
drawers and the motor/pulley assembly in the pedestals.
Yes. Not that the defense is perfect. I have pulled swarf out of just
about everywhere.
It does tend to get everywhere.
Enjoy,
DoN.
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