PM1022V Spindle Bore

I decided to elaborate. If I just spent a couple thousand dollars on a new lathe and it didn't pass a 1" bar through the spindle as it is specified to do, I don't think I would accept being told to bore it out.

In order for PM to say it has a 1" spindle bore, it is understood that it will allow a 1" rod to pass. That means the actual spindle bore must be larger than 1". The only way a 1" bar will not pass is if the spindle bore is exactly 1" ID or smaller or if the test bar is significantly larger than 1" or if the bar is not straight. Personally, I would confirm the OD of the bar and put it in V-blocks to confirm it is straight. Then I would call Matt himself and discuss options with him but boring or honing it out is not reasonable on a new machine.

And as an aside, I would not use drill rod for alignment. I would use Thomson linear shafting. It is case hardened, round, consistent in size and is straight. Drill rod has too many variables, straightness being an important one.
 
Thank you for saying that. I kind of agree. This was a giant purchase for me and after the hell of getting the machines into my basement and mounted on my benches I can't imagine returning them. So I figured that I'd act like a hobby machinist and fix the issue on my own.

The idea of the v blocks is a good one. I will buy some and measure again. But I'm pretty sure the OD is correct.
 
Your first lathe is not only a major purchase in dollars; its a big deal in your hobby career. The lathe should work as specified. I think a discussion with Matt is in order because fixing this issue is not a little thing.

Boring it is not realistic. You need a 3/4 to 7/8" carbide bar (major bucks, and you actually need to know how to bore) due to the size and depth of the bore, and that will only get you halfway into the bore; you can't bore the other half, at least not accurately. Honing might work better if you can find an extension to go 8" deep and hone from each end.

Do you not have a micrometer to confirm the OD? How about a decent dial or electronic caliper? Just something to measure it so you can tell Matt that the test piece was confirmed to be 1" OD.

Correctly checking for straightness requires V-blocks, a surface or height gauge, an accurate indicator and ideally a surface plate. In your shoes, I would just find a really flat surface and roll the rod on it to see if it jumps. I have seen drill rod with significant warpage, which is why I suggested linear shafting instead.
 
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I have a regular caliper but not a micrometer.. (I bought one but it hasn't arrived yet). I do have a few nice indicators and a surface plate so I feel like I can come up with a way with vblocks to check the straightness.

Is Matt the owner of PM? I've been just dealing with people via emails..
 
Yup, Matt is the owner and you should be speaking to him. He has an outstanding reputation on this forum. I'm sure he will make things right.
 
Hi Tom, Guys,

A "D" bit would laugh at taking off 16 thou, and could easily be done from the tailstock.
Lots of lube and a nice slow feed !
 
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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