In article . com,
TheAndroid wrote:
I am working with an old 1974 Clausing 8052. The lathe itself seems to
be in really good condition. I am using the machine after it has sat
idle for a long time. No manuals exist in the shop and the topslide
will not move. The feed handle turns (there is quite a bit of backlash)
but the slide stays in one place.
I've seen several good posts, but one thing which I have not yet
seen mentioned is the possibility of a taper turning attachment (a
sliding block on an adjustable angled piece) being mounted behind the
carriage. If that is present, and locked, then it will prevent the
cross-slide from moving except by moving the carriage towards/away-from
the headstock, depending on the angle that the adjustable piece is set
to.
It has an Aloris toolpost on it and I suspect the topslide has been
locked somehow. I loosened the gib screws but got no movement out of
it. Any ideas? Maybe a soft whack with a hammer?
Only after all else is dealt with. You've got good advice on
that part of things.
Also, with the Aloris, is there an optimium angle for the compound to
be at?
There are several optimum angles -- to be discussed when I get
into the letter-designated paragraphs below.
Once I get the compound moving, I may have to change the
rotation of the tool block. I want to get it right.
My own preference is to mount the toolpost so one dovetail is
parallel to the lathe bed, and the other is parallel to the chuck face.
This means that:
1) You can turn with a properly oriented tool mounted on the
dovetail closest to the chuck. (My favorite for the moment is
the BXA 16N holder which has mounts for two carbide inserts, one
in turning position and one in facing position. (You don't
say which size of Aloris toolpost you have, so you may need a
different size of the 16N. (The 'N' is for "negative rake", and
I usually use inserts with a groove which makes them into
positive rake cutting with a negative rake holder.) Anyway, the
16N (or plain 16, for positive rake tools) is a very rigid
toolholder for inserts. Much more rigid than a combination of a
tool holder and a bar for the insert tooling. (It is useless,
of course, for HSS tooling, unless you can find a matching
HSS insert -- which I have not yet seen.)
2) You can just as easily face by shifting a tool holder to the
dovetail closest to the centerline of the lathe.
3) A carbide insert external threading tool will be in the right
orientation to work without adjustment in the turning dovetail
described in (1) above.
4) A boring bar will be parallel to the axis when mounted in the
facing dovetail.
5) A carbide insert internal threading tool will be in the proper
orientation when mounted in a toolholder in the facing dovetail.
All of this without having to disturb the setting of the
toolpost itself.
Note, however, that you *will* need to re-set the post whenever
you change the angle of the compound. Common settings for common
operations a
a) Handcrank 29-1/2 degrees to the right of cross-slide for normal
60 degree threading.
b) Handcrank 29-1/2 degrees to the left of cross-slide for
internal 60 degree threading.
c) Handcrank 14 degrees to the right of cross-slide for external
ACME threading.
d) Handcrank 14 degrees to the left of cross-slide for internal
ACME threading.
e-f) Handcrank 27 degrees to the right or left of the cross-slide
for external/internal Whitworth (55 degree) threading.
g) And whatever feels right (45 degrees, 60 degrees, or whatever
for chamfering the edge of a workpiece.
For all of those except perhaps (g) above, you will want to
re-set the toolpost after shifting the compound. But some chamfering
can be done with a properly-oriented tool edge -- ideally one which is
set up for the toolpost to be in the normal parallel to chuck face and
axis position.
Good Luck,
DoN.
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