09-22-2016, 06:12 PM
(This post was last modified: 09-22-2016, 06:14 PM by the penguin.)
I went to work at 2:30 am and got home at 4:30 pm, long day. I still had some shop time, I got 8 parts that have to go out the door.
So I had some lathe time to finish up , I talked to Ken (Pixman) last night, having a bad time get a acceptable finish on a piece of 1-1/2" ground and polished shafting. As I was trying to face the end of the shaft, I was tearing the metal, not cutting it. I finally gave up for the night, got my 3-1/2 hours of sleep and then went to work.
So today with a hopefully somewhat clearer mind, I picked up where I left off last night. I had a 10" piece of scrap shafting, chucked it up and started to do some research. I checked tool height, my compound setting and started to play with the feeds and speeds. I finally good a very good result, finished off the job, so I can now relax.
I rechucked the shaft chunk, I took out the majority of the tools I got set up and compared the tools at various feed and speeds, some of the results surprised me. By far the best looking finish came with the Aloris #16 tool with a TPG-321, but the max depth of cut was down to about .020" -.030", above that the quality dropped off drastically.
The CCMT 32.51, insert gave a very good finish, but again depth of cut was somewhat limited.
The tools using the CNMG and WNMG inserts, had an acceptable, though slightly rougher finish, but the depth of cut was incredible, I was taking cuts over .120" with ease and the finish seemed the same regardless of depth of cut.
I also ran a couple of Grizzly marketed tools and few other cheapies and got somewhat variable results, but these were used just to check, some I haven't used in years.
Obviously these observation are done by a boiler technician, who owns a few machine tools, not a machinist, who knows, I still might be doing something completely wrong. This was also, only facing the end of the shaft, I didn't do any turning. Who knows, maybe I just need more sleep.
So I had some lathe time to finish up , I talked to Ken (Pixman) last night, having a bad time get a acceptable finish on a piece of 1-1/2" ground and polished shafting. As I was trying to face the end of the shaft, I was tearing the metal, not cutting it. I finally gave up for the night, got my 3-1/2 hours of sleep and then went to work.
So today with a hopefully somewhat clearer mind, I picked up where I left off last night. I had a 10" piece of scrap shafting, chucked it up and started to do some research. I checked tool height, my compound setting and started to play with the feeds and speeds. I finally good a very good result, finished off the job, so I can now relax.
I rechucked the shaft chunk, I took out the majority of the tools I got set up and compared the tools at various feed and speeds, some of the results surprised me. By far the best looking finish came with the Aloris #16 tool with a TPG-321, but the max depth of cut was down to about .020" -.030", above that the quality dropped off drastically.
The CCMT 32.51, insert gave a very good finish, but again depth of cut was somewhat limited.
The tools using the CNMG and WNMG inserts, had an acceptable, though slightly rougher finish, but the depth of cut was incredible, I was taking cuts over .120" with ease and the finish seemed the same regardless of depth of cut.
I also ran a couple of Grizzly marketed tools and few other cheapies and got somewhat variable results, but these were used just to check, some I haven't used in years.
Obviously these observation are done by a boiler technician, who owns a few machine tools, not a machinist, who knows, I still might be doing something completely wrong. This was also, only facing the end of the shaft, I didn't do any turning. Who knows, maybe I just need more sleep.
jack