Re: [CAD_CAM_EDM_DRO] Re: My Logan Clunker & leadscrew compensation

Jack,

> Not being an EMC programmer it's easy to think a software solution
> would be "easy." It would seem possible to implement this type of
> error correction as a piecewise linear transform of the output
> coordinate system.

With a stepper system, the correction for shallow taper is going to come
in discrete steps. With my MaxNC bolted to the cross slide of a 16"
engine lathe, I made gently tapered core pins for a rubber compression
mold. I thought I'd gotten a real nice finish until I went to put a good
polish on it. The discrete stepping of the motors didn't follow the
exact taper as well as I thought, and there was a very repeatable
pattern along the surface essentially showing me the deviation!

> Jon, any chance that you could post a picture to your website or the
> cced archives of the setup you described ?

http://www.prototype-design.com/cnclathe.htm

Shows both the MaxNC attached to my Clausing and the setup I'm building
now.

> There's another mechanical problem associated with worn v-ways. If
> the carriage is adjusted to be a nice sliding fit on the unworn
> areas, it's sloppy on the worn spots etc. I can imagine a smart
> electro-mechanical adjuster, but I don't immediately see a practical
> solution to this problem.

Sorry to say, the only REAL solution is to get the bed ground, then
realign everything. It's easiest to restore the carraige with Moglice or
Turcite, but it's a LOT of work. I wanted to restored a 12" South Bend,
but was looking at close to a grand if I did everything but the bed
grinding, up to $3500 or more to have a rebuilder/scraper do it.

Jon