PM1022V Spindle Bore

I did a quicky division there: 25.38 mm = 0.9992125984 I figured it was close enough
I usually use 0.0394 for 1 mm (rounding up slightly) so 1/.0394 = 25.38
mark
I'm giving myself a Spock nerve pinch for being so terribly inaccurate :eek 2:
 
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I've got a 15+ year old Grizzly 10-22 that is very siniar to the PM that you have. You got me wondering, I've never measured mine, so I grabbed a piece of 1" dia. drill rod and it slides through effortlessly. I took my inside calipers and for at least the 4 or so inches on each end that I can get to with them meaure out to be 1.020" + - .005. (1" does equal 25.400 mm)
 
Janderso said:
Drilling out a spindle bore on a new lathe or any lathe without proper "line bore milling" set up and equipment would scare the hell out of me.
I am leaning toward PM products down the road. This post concerns me. If it is a metric size, they should advertise the correct spec.
My 2 cents.
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I would continue leaning toward PM stuff - they sell good products for the money. I would ask Matt to confirm that the spindle is the right size before shipping, especially if you're buying a larger lathe. Larger lathes beyond the 10" models usually have induction hardened spindles and you will NOT be boring or drilling them if they're too small. I have to admit that this is the first time I've heard of this problem on a PM lathe.
 
neodem said:
So I just took possession of a new PM1022 and I bought I long drill rod (1" OD) to use to test the alignment and even though the PM has an advertised bore of 1" I found that I couldn't pass the rod through the bore. It ended up getting stuck about 1/2 way through.

Apparently it's not exactly 1" but a fraction less. The PM support person suggested that I could use a boring bar to open it up a little bit. Has anyone done this before?
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I had to open the head stock on a small Craftsman lathe. I chucked a long reamer in the tail stock and bored the head stock with LOTS of cutting fluid and backing out frequently.
 
I just passed a 1.000 12L14 (cold formed) bar thru the spindle of my brany new 10 30 PM lathe. The bar has approximately .008 movement on the chuck end when I pushed two pieces of .002 shim in on the other end. I am going to assume that it's concentric.

I just realizedd, I first tried it from the outboard end, the rod hit a stop. (step?) From the chuck end it wiggled right through.
 
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Measured the ID of the spindle bore and it easily accepts a 1.035 brass turning on either side of the spindle, BUT, stops approx. 4.5" into the bore on each side. I'm going to turn down the brass to 1" and try again.
 
I was disappointed when I got my (used but extremely well cared for)
1998? 10-22 and couldn’t pass a 1” shaft through. I’ve never needed to put a 1” shaft through it, but the best I can tell it’s undersized right around in its center by about .002-3”
If I need to I would probably just use a hone like a brake cylinder hone to open just that central area. I have no idea what the newer ones spec out to.
 
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