Got this in a box of treasures. Have any of you used one? It's a commutator cutter. PK
I've been looking at the pics a lot but I'm not sure exactly how it works.
Here are some drawings. I'm missing a few small parts. PK
When you said commutator cutter I thought you were talking about timers, being that Ford called them commutators.
Lol maybe that's part of what is throwing me off. I still saw the drawings and thought "What in the world does this have to do with the timer?" Lol, I had never heard the "commutator" before until I started fooling with Ts. So if it isn't a Ford Roller Timer, what else can "commutator" refer to?
Ah ha! Google is my friend. I'm tracking now. =)
There are different versions of this tool. They are pretty clever, a way to center the armature and turn it, with a very fine thread to advance the cutting tool, and some come with an under cutter feature (to cut the insulating material below the contact surface). I think I used one decades ago, but now I have a lathe, so it's just a "curiosity" in my garage now. Mine is made to clamp in a vise, which I think all the different versions do too. Most folks had vices (workshop ones, not personality ones!) but few had lathes, and some folks didn't have electricity!
Sorry for the confusion. I always call the Ford commutator a timer. The earliest drawings I can find of this tool is 1939. The brass lever swings out and releases the thread so the cutter can be pulled back for another cut. Interesting tool. PK
Cool! I have a similar one in a box with the original instructions from about the same era.
I've never seen one of those tools before, but from looking at the drawings, I think I have a basic idea how it must work.
The generator armature is supported in a stationary position and the "tool" is clamped onto the "commutator" end of the shaft by the part of the tool that looks like a collett. The "brass lever" is then pulled out to engage a "follower" to follow the screw thread portion of the tool as the tool is rotated around the stationary armature, and the cutting tool is adjusted so as to take a light cut off of the commutator segments, slowly advancing across the full width of the commutator until all segments have been "resurfaced". I guess you could say that it works opposite of the way a lathe works. Instead of the lathe being stationary and "the work" being turned, this tool is like a lathe and cutting tool being rotated around the stationary work while the screw thread portion of the tool advances the cutting tool across the commutator segments.
It appears to me that the "missing small parts" are used to clean out the spaces between the commutator segments after the tool has been used to "clean up" the surface of the commutator. To do this, I would presume that the cutting tool is replaced with a slightly different type of tool, that is lined up with each "space" between commutator segments, and as the lever (missing) is actuated, the tool makes a pass through the space between two commutator segments to clean it out, and the tool is then slightly rotated to the next space, and so on until all spaces have been cleaned out.
Anyway, that's the way it looks to me! Neat tool! For what it's worth,.......harold
From what I can see, it uses a standard 5C collet to clamp the tool to the armature shaft.
These are readily available in a wide variety of I.D. sizes in both standard and metric thus making it useable on any diameter armature shaft that fits within the 5C collet range.
5C collets can be purchased at most machinist supply outlets like Enco.
Mike, according to the patent drawings, the collet is an R8 style. 5C collets are threaded externally but, R8 collets are threaded internally, like this shows. Everything you say about the 5C is applicable to the R8.