jcfx: Thanks for your reply.jcfx wrote: ↑Sun Jun 02, 2019 1:42 amWolfgang,
I have two sets of L20 collets that came with my V10P and Maximat 7, both sets are Schaublin that American Edelstaal
offered as an accessory for the Emco lathes.
The Maximat 7's were in near mint condition in a fitted Edelstaal wood box, unfortunately the V10P set came
loose in a cardboard box. I have never checked them for runout since I don't have a set of gauge pins.
I just spun my V10P's spindle and when I'm in gear I feel the gears in the headstock meshing ever so slightly
so it feels "rough" if I diddle with the gear shift paddles till the gears don't mesh the spindle is smooth as silk.
Could it be that you're feeling the gears ? Perhaps your friends V10P has a heavier weight oil in the headstock
versus the OEM recommended 10 wt and it's "smoothing out" the gears meshing ?
It's worth a look inside, as you might know the shift forks in Emco lathes are Zamak, some batches are prone to cracking,
my Maximat 7 is out of service because of a cracked shift fork ( I caught it in time during an oil change ).
I did add an oil additive to the headstock oil bath some years ago; perhaps it is time to change all the oil with the installation of new bearings.
I'll thoroughly clean out the headstock gear box before installing new bearings. I'm thinking of using automotive manual transmission oil in the headstock. I may have some synthetic oil left over from years ago.
Turning the spindle by hand: Yes indeed it is important to have the gear train in "neutral" ie. no gears engaged with any spindle gear when doing this test. Further, a very small chuck or catch plate are also necessary to check for bearing smoothness by hand. I typically have a 6" Pratt Burnert chuck on the spindle (came with the lathe) and this huge chuck (huge for a 10" lathe) has such a large moment of rotational inertia that any bearing roughness is easily obscured.
If you have a moment I'd appreciate it very much if you were to test your spindle with two standard sized collets, say 1/2", or 3/8", or 1/4" using a dowel pin or a short piece of ground rod such as drill rod, and advise your run-out test results here. When I checked my collets I used these standard dia. and was perturbed when every single stinking collet so tested ran out .0005" TIR.
armscor: Those fibre gears are incredibly tough. I have done much serious turning of square blocks on this lathe and the fibre gears were fine last time I checked. Just don't try to change gears with the spindle running as this is definitely NOT a syncromesh box.
For successful parting off the lathe needs to be mounted to a rigid bench. I went one step further and built a new mounting base for the compound rest that supports the base slide of the compound rest to its very end. This new base is also 1/8" or so lower so that the quick-change tool holders I built soon after getting the lathe would have at least a 3/8" thick support under the 3/8" square tool bit. This has worked very well.
However, parting tool geometry remains important and I confess that, when I was given a commercial parting tool with tungsten carbide inserts, I use this tool preferentially when parting off steel. For aluminum and brass I use the home-ground tool. w