Ye Olde Comm Lathes: Need Some Info...

[EddieO]

The indexable cutters do not work very well....we tried them on the few lathes they worked on.....did not work very well.

If the sharpie works as a visual guide, its fine...just dont think its critical in getting a good cut. While Big Jim and others felt it kinda acted as a lube, Big Jim (who used to work for me) admitted to me it was more an old habit than really do anything with the cut....

On the 550 lathe....my advice would be to find a hudy that is adjustable for a 550. Probably a lot cheaper and less headache then trying to fabricate a 550 extension. I just built a 550 version of the fantom lathe....and it was quite the undertaking....and its supports are fixed. If you are still stuck on doing it, you will want some type of dovetail or the like on the back side (the hudy has this). You literally want the ability to be out of parrellel with the other side to near nothing.... .0005 or less. Even .001 over a couple inches will turn into a fair amount of runout at the comm along with the wear on the guides. Many of the lathes like yours took some tweaking to get them to cut well back in the day, as the blocks were often out of alignment...before I switched to Fantoms, I had taken my other lathes into my uncle (who is a machinist). He squared them all up for me with his fancy tools...he told me some were pretty bad, two of which were brand new in the box still.

Ah fan glue...usually is not that much, but makes sense...

Later EddieO

[crawlinwithacat]

Yeah... Whether or not it actually becomes practical is not exactly the top of my list lol. More of somthing new to learn since i have never done any CAD design. I tend to find excuses to learn new things that would take too much time to learn withought a project. The project justifies the time spent learning. So if the end result doesn't really work, I don't mind so much because I was able to learn a new skill. So like you're saying, I am probably better off buying a lathe designed for 550s. Thanks for all your input Eddie!

[garyk]

Dug out the old comm lathes from oval racing years ago...never thought I'd need those again. I was going to sell them but having just got into crawlers last year I'm now finding I like a good brushed motor in my crawlers, so keeping a comm lathe around seems like a good idea now. One of mine is the typical style, the other is designed to cut the comm while its inside the can! I guess we used that for cutting comms on sealed motors back in the day, not much use now though.

[dwentz]

A good small hobby metal cutting lathe will work nice, and you can use it for other things. I have cut a few on my little Taig lathe. I grind my own cutting tools out of high speed steel. Not much to it.