Cross slide nut no good.....PM1440GS

Firstgear said:
And that is why I am an apprentice to the apprentice!
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Ha, no worries.

I stripped one of mine about 2 weeks ago, too. Wanted to initially modify just for the ease of using SHCS to adjust instead of the open-ended wrench method (I have the std PM1236). Parts needed to be made, so I put it off. Of course, it stripped at the absolute worst time ... night before a shipping deadline. :bang head:

Great machines, but they do need some TLC in those places that corners are cut to make them at lower cost.
 
I actually just replaced mine and yes they were alittle mangled. Mine weren’t a tight fit in the slot they had a lot of room side to side and thickness. As you can see in you picture the pieces were cut straight and the slot is cross slide is a circle. Mine showed the corner pooched over from the not spinning in the slot and not seating on both sides of the slot like it was cocked in there. So I made four of them with a slip fit on thickness and I radiused the innner and outer diameters to match radius of slot. I made four so when I install the solid tool post block I will use the existing mount but four instead of two hold down bolts. I change the thread to a 3/8-24 so I could change to a quality american screw that wont strip too. Warning watch your length of screw so it doesn’t blow out the bottom of slot pretty thin there. I’ve read stories of people breaking that slot from uneven surfaces when bolting together. Good luck
 
Good to know. Thanks for the heads up. I dont move my compound very much, I set it to 29° when I got my lathe and rarely move it.
Pm1440gs here
 
Cadillac said:
I actually just replaced mine and yes they were alittle mangled. Mine weren’t a tight fit in the slot they had a lot of room side to side and thickness. As you can see in you picture the pieces were cut straight and the slot is cross slide is a circle. Mine showed the corner pooched over from the not spinning in the slot and not seating on both sides of the slot like it was cocked in there. So I made four of them with a slip fit on thickness and I radiused the innner and outer diameters to match radius of slot. I made four so when I install the solid tool post block I will use the existing mount but four instead of two hold down bolts. I change the thread to a 3/8-24 so I could change to a quality american screw that wont strip too. Warning watch your length of screw so it doesn’t blow out the bottom of slot pretty thin there. I’ve read stories of people breaking that slot from uneven surfaces when bolting together. Good luck
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You are correct, it is thin in that area and the thread engagement is not much with a socket head cap screw. I say this because the cap screw needs to have a 90 taper on the head to match up with the taper in the compound. I was going to take everything apart and only got so far when I decided to put it back together and purchase the correct flat socket cap screw from McMaster-Carr. I can order from them today and it arrives the next day so pretty convenient. I have contacted PM about it and they are sending me new parts....I am hoping that the parts are better than what I got with the machine.
 
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