Gilrock
Member
I think so...because "Parting is such sweet sorrow." :biggrin:
Anyways I figured I'd open a new thread instead of turning the lathe purchase decision thread into a parting discussion.
So I watched the 3 videos from the link skiprat provided here:
http://www.penturners.org/forum/f166/baileigh-vs-precision-matthews-103022/index4.html#post1460948
If you listen around 2:20 in video #1 he says that parting can be difficult on smaller hobby lathes for the home machinist but then I've already found that out. One thing the video did was give me a little more confidence with parting off aluminum. He was spinning the dial about as fast as he could with no issue. I can't go quite that fast but I tried last night and I'm able to move much faster than I have been.
Then I went back to the hard stuff. I parted off a piece of 5/8" O1 tool steel. I got the job done but I took like 10 minutes. I tried 2 different blades one of which has carbide brazed on the edge. I freshly sharpened the blades. I made the setup as rigid as is possible with my current setup. My blade just doesn't cut into the steel anywhere near like what I see in the video. I tried a couple different speeds. He was using 600 rpm so I tried that and didn't get anywhere. I had better luck at 300 rpm. What I observe is as the blade hits the steel it doesn't start to dig in...it just seems to build up pressure. That's the part that kinda scares me because I can feel it taking too much pressure for me to turn the knob with nothing happening. If I just let go at this point I can hear it rub for several seconds then all of sudden it seems to bite and dig in and makes a cut. This sudden dig in is where I've had major issues before. The only thing I can think of that might be wrong is I could be a few thousandths above the centerline. The problem is my tool holder is bottomed out...it won't go any lower. I've got the Phase II AXA 100 QCTP with the parting tool holder that fits it. Another thing I see in the video is he mentioned the blade being perpendicular but my tool holder is designed to hold the blade at an angle. I forget but it's something like 4 or 7 degree rake. Since I had so much chatter to be safe I kept advancing the blade in a few thousandths and then moving it over a few and advancing in again. Just keep repeating back and forth so that theres a little room if the chatter vibrates the blade. I actually got that technique from "Chris's Tips" underneath the section where you order the parting blades from LMS.
Anyways I just don't know if my lathe is big or rigid enough to part that tool steel cleanly like I see in that video. Even that other video where the guy had the small lathe making big cuts he says it was "a stunt" and that it was risking burning up the electronics. I could also tell he had made a lot of custom pieces to that lathe which must have improved rigidity issues. He also was able to manually feather the speed during the cut...something my lathe isn't capable of.
So I still think if I ever get a chance to upgrade I'll be seriously considering that Precision Matthews 1127VF. Although it may be dangerous...Justin (Timebandit) got one and has never been heard from again. Joking of course but I have missed seeing him around the forum...I used to have half his posts bookmarked when I was learning what taps and dies and drill bits to use for starting kitless.
Anyways I figured I'd open a new thread instead of turning the lathe purchase decision thread into a parting discussion.
So I watched the 3 videos from the link skiprat provided here:
http://www.penturners.org/forum/f166/baileigh-vs-precision-matthews-103022/index4.html#post1460948
If you listen around 2:20 in video #1 he says that parting can be difficult on smaller hobby lathes for the home machinist but then I've already found that out. One thing the video did was give me a little more confidence with parting off aluminum. He was spinning the dial about as fast as he could with no issue. I can't go quite that fast but I tried last night and I'm able to move much faster than I have been.
Then I went back to the hard stuff. I parted off a piece of 5/8" O1 tool steel. I got the job done but I took like 10 minutes. I tried 2 different blades one of which has carbide brazed on the edge. I freshly sharpened the blades. I made the setup as rigid as is possible with my current setup. My blade just doesn't cut into the steel anywhere near like what I see in the video. I tried a couple different speeds. He was using 600 rpm so I tried that and didn't get anywhere. I had better luck at 300 rpm. What I observe is as the blade hits the steel it doesn't start to dig in...it just seems to build up pressure. That's the part that kinda scares me because I can feel it taking too much pressure for me to turn the knob with nothing happening. If I just let go at this point I can hear it rub for several seconds then all of sudden it seems to bite and dig in and makes a cut. This sudden dig in is where I've had major issues before. The only thing I can think of that might be wrong is I could be a few thousandths above the centerline. The problem is my tool holder is bottomed out...it won't go any lower. I've got the Phase II AXA 100 QCTP with the parting tool holder that fits it. Another thing I see in the video is he mentioned the blade being perpendicular but my tool holder is designed to hold the blade at an angle. I forget but it's something like 4 or 7 degree rake. Since I had so much chatter to be safe I kept advancing the blade in a few thousandths and then moving it over a few and advancing in again. Just keep repeating back and forth so that theres a little room if the chatter vibrates the blade. I actually got that technique from "Chris's Tips" underneath the section where you order the parting blades from LMS.
Anyways I just don't know if my lathe is big or rigid enough to part that tool steel cleanly like I see in that video. Even that other video where the guy had the small lathe making big cuts he says it was "a stunt" and that it was risking burning up the electronics. I could also tell he had made a lot of custom pieces to that lathe which must have improved rigidity issues. He also was able to manually feather the speed during the cut...something my lathe isn't capable of.
So I still think if I ever get a chance to upgrade I'll be seriously considering that Precision Matthews 1127VF. Although it may be dangerous...Justin (Timebandit) got one and has never been heard from again. Joking of course but I have missed seeing him around the forum...I used to have half his posts bookmarked when I was learning what taps and dies and drill bits to use for starting kitless.
