New mini-lathe user question

[mikey]

Thanks, "more" lead angle would be clockwise then right? So the shank leans towards the chuck?

Yes, turning the tool tip clockwise will give you more lead angle. If the tool is ground properly then finish definitely improves with more lead angle. If you encounter chatter, especially with thin work pieces, then reduce lead angle. When facing you are actually using negative lead angle.

 

[coolidge]

I'll give you a tip my brother gave me on my new Grizzly G4003G lathe, you want to angle the compound rest 20 degrees (or so) so that when you are in the cut the carriage is loaded up against the ways.

 

[shorton]

Thanks everybody, I appreciate the help.

 

[7HC]

Does this help at all?

M

 

[Railway Bob]

One of the best tutorials I have seen on the use of metal lathes, milling machines, and other machine shop tools is the series of YouTube videos put out by Tubalcain (mrpete222). He is a former shop teacher who is very good with his explanation of things. He has a series of videos on the South Bend lathe, the Atlas lathe and the Bridgeport milling machine.
http://www.youtube.com/user/mrpete222?feature=watch.

This would be a good assignment for the kids in your class to watch and learn on the use of these tools. Each video is from 10-15 minutes long with a couple that are a bit over 20 minutes. If longer, he breaks them down into a number of parts.

Another series of videos, although a bit more "professionally" oriented is Keith Fenner's videos. This series would be geared more towards students who are taking machine shop courses, but you could probably learn a lot from these videos.
http://www.youtube.com/user/KEF791/videos

Hope this helps.

Bob M.

 

[george wilson]

Use the above diagram to help orient tools. HSS tools are better for a light lathe.

Also,though,be sure to orient the tools in the holder so that if they slip some under the sideways pressure of a cut,they will swing AWAY from the metal instead of swinging into it,causing a deeper cut and possibly overloading or crashing the machine. This applies to any size lathe.

I'll also mention that round nosed tools are much harder for a small lathe to handle. They strain everything due to increased contact and cutting area on the metal. Your tools need to be rounded a LITTLE bit to make a smooth cut. But,the roundness only needs to be enough to span the width of the cut you are taking,in order to not leave a tiny "threaded" looking cut. I hope this is clear enough. In other words: If your sideways feed is .004" per revolution,a tip diameter of .008" will be plenty to span that width. You can gauge the diameter by eye as it would be hard to measure. You CAN open your dial caliper by that amount and see how big the diameter should look. Practice is important.

 

[Turbinedoctor]

Like Bob said Mrpete222. He has taught me a lot.

 

[shorton]

Use the above diagram to help orient tools. HSS tools are better for a light lathe.

Also,though,be sure to orient the tools in the holder so that if they slip some under the sideways pressure of a cut,they will swing AWAY from the metal instead of swinging into it,causing a deeper cut and possibly overloading or crashing the machine. This applies to any size lathe.

I'll also mention that round nosed tools are much harder for a small lathe to handle. They strain everything due to increased contact and cutting area on the metal. Your tools need to be rounded a LITTLE bit to make a smooth cut. But,the roundness only needs to be enough to span the width of the cut you are taking,in order to not leave a tiny "threaded" looking cut. I hope this is clear enough. In other words: If your sideways feed is .004" per revolution,a tip diameter of .008" will be plenty to span that width. You can gauge the diameter by eye as it would be hard to measure. You CAN open your dial caliper by that amount and see how big the diameter should look. Practice is important.

Thanks (some more) guys, that does help.