Well, I just had my first failure with my PM 1440. The cam-lock on the tailstock broke. This lathe has been just so amazing compared to my other Chinese lathes that I got my feelings hurt. LOL.
It wasn't a particulary hard fix. I had to pull and split the tailstock to remove the shaft, cam, and pull block. I found the cam was held to the shaft with a spring pin (or roll pin if you prefer). It had broken. I know why it had broken. Spring pins are strong, but not as strong as you might think. When ever I do some heavier drilling (like clear a hole with a 1" drill bit) I tend to bump the handle firmly with my hand. That cumulative force surely is what caused the pin to break.
The other issues is the pin is in my opinion a little short for the job. I think its a standard length pin though as I had several the same length in a box of assorted spring pins I bought a while back for emergencies. I think as a result the shorter than full depth engagement in the cam allows it to flex more when I bump the handle. Since I had a pin and I was in the middle of a project I put it back together and dialed the tailstock back in. I may find it hard to break the habit of bumping the handle so eventually I am sure it will fail again. When it does I would like to be ready with a better solution. My first thought was to use a solid stainless dowel cut to length. Throw some Loctite on it and call it a day. Drilling and reaming for a nice light interferrence fit might be tedious, but its within my capability. Just a few tenths so it stays in place, but can be driven out easily enough. If the fit is to both parts, the cam and the shaft, there shouldn't be any slop to allow the pin to cause wear. Are there any issues with that? The other thought I had was to make a new cam that has to be pressed onto the shaft eliminating another other possible play/wear issue. A one piece shaft and cam is not a practical solution. I'd have to drill out the side of the tail stock and the insert a bushing to support the shaft. Not impossible, but a lot of unnecessary work and seriously overkill. On the other hand it would probably outlast me. LOL.
This brings us to failure number two. After I put it back together I threw a piece of stock in the chuck and turned a point to align the tailstock to. Then I threw a dead center in the tail stock and started lining up the points. When I got out my loupe I found the center was blunt. Looked like maybe it was dropped. I couldn't see it with just my glasses on, but it was clear to see with the loupe. Thinking maybe I dropped it and didn't remember I got one out of the tool cart that had never been used before. It was also blunt. It was a nice tiny dome, but it was blunt. Orders of magnitude bigger than the tip on my turned point. Atleast it seemed uniform so I dialed it in as best I could. I realize even with hardened and ground steel handling is coming to take off needle tips from an object that heavy, so maybe that's the norm. I don't know. Both centers came with the lathe so perhaps they are just lower grade Chinese parts. Do all dead centers have a domed tip when looked at under a glass?