nighthawkFmobil
Plastic
- Joined
- Dec 23, 2019
Greetings, I'm new here and just as new to machining. First off I'd like to say thanks to all contributors on this site. The amount of information I've learned here is priceless.
Now as for my most recent issue. About a month ago I purchased my very first lathe Pm1228. The lathe and all the tooling I've recieved have been great so far aside from a few blemishes and what not I've been totally happy with the machines performance. Been learning a lot and was working exclusively with the 3 jaw that comes with the lathe until a couple days ago I decided to try out the 4 jaw I purchased from PM in addition to the lathe.
Right away I noticed the threads for the scrolls are a lot more stiff then the 3 jaw I recieved from them. Odd as everyone raves about the quality of Taiwanese products compared to Chinese products. Anyways after fiddling around with the studs I noticed that one of the cams would engage at a different spot then the other two when mounting it to spindle. When I ran the lathe It looked like something was wobbling and I was experiencing slightly more vibration. Being a newbie I didnt check the run out of the OD of the chuck or the back. I guess i just trusted PM wouldn't put out a weak product(not saying the verdict it out). Anyway I took a face cut of .032" and it was beautiful. Then i went to turn the diamater with a .060" doc and bang instant chatter. As bad if not worse than when I part and dont feed fast enough. I flipped the power feed off quickly but Figured it was rubbing and reduced doc to .050". It was better but still not even close to what I was getting with 3 jaw. Decided to check run out of OD of chuck and sure enough it was out about .002". I removed and reinstalled then camlocks tightening the in a more incremental fashion and reduced the run out to about .0015" but ran out of time last night to try and zero it in. Honestly one of the camlock studs was all nasty and had a little rust while still in the packaging and it threw me off. Like why is this company with a phenomenal reputation sending me stuff from tawain which also has a good all around reputation that has rust on it while its still in original packaging. While i was installing the camlocks doing the whole if it falls between 6 and 9 or 1 t to 3 thing I noticed the indicator ring(for lack if a better term) on one of the camlock studs is at a different height along the stud vs the other two. For instance when the studs are bottomed out in the threads the indicator ring sits higher then the other two. So obviously when it its position to lock it's at a different height. I have a feeling one of my locking studs is just off.
After doing this I checked the nose onnmy spindle to see if I possibly damaged the surface running a chuck off center but it was like hardly registering any movement on my .001" indicator so probably less than .0002". Is there anywhere else I should check for damage? It looked like it was good but I'd just like to make sure. Very frustrating to pay extra for something and it doesnt even work right out of the box. The chuck manual says less than .00098"of runout. This is frustrating
I'm going to run home for lunch and mess around with it but I feel like it shouldn't be so questionable. A quick google brings up a youtube video of someone last year having exact same issue. Also other mentions of people having issues with the scroll threads being all out of whack. LoL after all typing I guess I'm just venting cause all i can really do is screw around with the camlock stud positioning which I already have quite a bit as well as tighten it more incrementally. To me its wonky that the damn thing is that sensitive if that's the case. I've already been pretty careful not to tighten the cams unevenly.
Guess I'm just looking for people who have had good or bad experiences with the PM 8" 4 jaw chuck. LmK thanks
Now as for my most recent issue. About a month ago I purchased my very first lathe Pm1228. The lathe and all the tooling I've recieved have been great so far aside from a few blemishes and what not I've been totally happy with the machines performance. Been learning a lot and was working exclusively with the 3 jaw that comes with the lathe until a couple days ago I decided to try out the 4 jaw I purchased from PM in addition to the lathe.
Right away I noticed the threads for the scrolls are a lot more stiff then the 3 jaw I recieved from them. Odd as everyone raves about the quality of Taiwanese products compared to Chinese products. Anyways after fiddling around with the studs I noticed that one of the cams would engage at a different spot then the other two when mounting it to spindle. When I ran the lathe It looked like something was wobbling and I was experiencing slightly more vibration. Being a newbie I didnt check the run out of the OD of the chuck or the back. I guess i just trusted PM wouldn't put out a weak product(not saying the verdict it out). Anyway I took a face cut of .032" and it was beautiful. Then i went to turn the diamater with a .060" doc and bang instant chatter. As bad if not worse than when I part and dont feed fast enough. I flipped the power feed off quickly but Figured it was rubbing and reduced doc to .050". It was better but still not even close to what I was getting with 3 jaw. Decided to check run out of OD of chuck and sure enough it was out about .002". I removed and reinstalled then camlocks tightening the in a more incremental fashion and reduced the run out to about .0015" but ran out of time last night to try and zero it in. Honestly one of the camlock studs was all nasty and had a little rust while still in the packaging and it threw me off. Like why is this company with a phenomenal reputation sending me stuff from tawain which also has a good all around reputation that has rust on it while its still in original packaging. While i was installing the camlocks doing the whole if it falls between 6 and 9 or 1 t to 3 thing I noticed the indicator ring(for lack if a better term) on one of the camlock studs is at a different height along the stud vs the other two. For instance when the studs are bottomed out in the threads the indicator ring sits higher then the other two. So obviously when it its position to lock it's at a different height. I have a feeling one of my locking studs is just off.
After doing this I checked the nose onnmy spindle to see if I possibly damaged the surface running a chuck off center but it was like hardly registering any movement on my .001" indicator so probably less than .0002". Is there anywhere else I should check for damage? It looked like it was good but I'd just like to make sure. Very frustrating to pay extra for something and it doesnt even work right out of the box. The chuck manual says less than .00098"of runout. This is frustrating
I'm going to run home for lunch and mess around with it but I feel like it shouldn't be so questionable. A quick google brings up a youtube video of someone last year having exact same issue. Also other mentions of people having issues with the scroll threads being all out of whack. LoL after all typing I guess I'm just venting cause all i can really do is screw around with the camlock stud positioning which I already have quite a bit as well as tighten it more incrementally. To me its wonky that the damn thing is that sensitive if that's the case. I've already been pretty careful not to tighten the cams unevenly.
Guess I'm just looking for people who have had good or bad experiences with the PM 8" 4 jaw chuck. LmK thanks
