Myford Super 7 questions

I am considering having my Super 7 reground and fitted with a new saddle
How can I get an indication of the condition of the spindle bearings? Is
there some simple tests I can do see if they will need work? As it
stands, the only practical issue I have with the machine is the ability
to get a decent finish in mild steel (unknown grade) without running
very slowly - bottom open speed for 1" diameter parts. I have adjusted
the bed to turn accurately and a test piece shows variation of about
0.0002 over 4" which seems perfectly OK to me.
The bed is a bit worn and is just about at the limits Myford suggest
before a regrind is needed. The carriage tightens a bit towards the
tailstock but does not jam.
So, after a regrind, just how tricky is it going to be to get the
headstock back on and aligned correctly? That is the bit that really
puts me off. Oh, and repainting of course - not looking forward to that.
Finally, the countershaft and spindle have been 'generously' lubricated
and the pulleys and belt are very slippery. the best depth of cut I can
manage in steel is about 0.040" with 0.003" feed before the belt slips.
Should the pulleys be dry or are they expected to get oily? I can't
really see how you avoid oil in there with everything open and all.
Any other thoughts/warnings before I start to take it all apart?
Reply to
Peter Harrison
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I had my Super 7 reground some while back including the saddle to ensure that both were matched as Myford do the reassembly of the saddle to the bed.
The headstock realignment is quite straight forward as in the side of the bed there are two adjusting screws ( well there is on mine) so the head can be nipped up and then clocked to be parallel with a test bar in the chuck and finally tightened well down. After that of course the tailstock needs a check too.
I would take advantage of the head being off to replace the drive belt. It will get some oil on it with use but should not slip as badly you indicate. I presume you are sure it's the belt and not the clutch?
The Myford handbook gives the preloading procedure and adjustment of the rear bearing adjustment to get the spindle position right in its tapered bearing. You will see if there is any problem with the tapered bearing when you have the spindle out. Unless you are very unfortunate it will not be oval and the adjustment procedure will give the right running clearance. A simple check when reassembled is to take a cut and see if the chuck tries to stall, if it does the preloading is too much. Too little and you can measure the chuck movement outwards and inwards with a DTI. The oil meniscus around the bearing when running is a good indicator too as it will change with loading if the spindle is not set well.
Reply to
Alan Marshall

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