Gyrobob wrote on 10/17/12 at 18:29:04:ralfyguy wrote on 10/17/12 at 16:22:06:Usually carbide lathe tools have a rounded corners on the cutting tip. If you grind that to a 45 degree flat bevel about a 1/16" wide and run the lathe At real high speed with slow and careful advance, it cuts nice and smooth and also resists breaking the tip from the hammering of the uneven surface. Just don't grind the bevel any wider than that, or the lateral forces are going to be too much and might rip the pulley out of the chuck. It's doable, but takes time and patience. Machining Titanium is much worse.
how do you know so much about this stuff? I'm a machinist by trade from Germany, immigrated to Oklahoma in 2000, currently not in the trade anymore. I obtained a Master's degree in industrial engineering in Germany. I used to design fully automatic production machines. A hard exhausting job with very long hours and hardly any free time and certainly no room for serious private relationships. Most of these machines were prototypes from scratch. My biggest project was a fully computer controlled, pneumatic cylinders operating machine that welded dashboards for the Mercedes S-Class together utilizing ultrasonic welding with Titanium Sonotrodes. They had to be machined out of billet Titanium, a wonderful material, but a horror for machining, especially threading and turning. When I took the job, there was just two barebones steel frames, one for left hand steering models, the other for right hand steering. The boss showed me the finished hand welded product and said that this machine is supposed to do that fully automatic without supervision in three months. Both sides! I had to do the entire design, machining of every single part, ordering the materials and valves and controls for the pneumatics, go and pick them up at the manufacturers, get the machines finished and running, program the computers, take the machines apart, put them on a truck, deliver to the Mercedes plant, put them back together and spend a week monitoring the function in the production line.
Messing with Titanium is one of the toughest challenges, especially with sonotrodes that had to be tuned for a specific required (amplitude) frequency. That means in and out of the lathe or mill, shave another thousand of a millimeter off and test, test, test.
Sometimes they were made from already hardened steel and you could not anneal them to make the soft for machining.
This is where you get the hang of it.
I gave up my career to marry a beautiful Lady from Oklahoma, and leave everything behind in Germany.