Re: [CAD_CAM_EDM_DRO] all-thread question

In a message dated 06-Mar-02 00:16:56 Central Standard Time,
rh@... writes:

> After looking up the prices on Ball screws I am planning on using all-thread
> attached to a stepper motor for the
> motion control. Will this be an acceptable and usable alternative or am I
> wasting my time ?

RH: Here's MY ignernt opinion (I have built lotsa home-brew CNC "X-Y"
machines and lathes): Rolled ACME with preloaded Turcite nuts (that's a
fiber-filled teflon secret stuff) will work fine for "learning what it's all
about"; indeed, if done right and well, you can make "professional" machinery
with that from Ball Screws & Actuators Corp. in San Jose, CA.

"All Thread" is for bolting concrete-forms together! The zinc-plated stuff
you find at Home Depot and ACE Hardware are just about almost good enough for
that, but much, much too rough even for "play-like" CNC experiments! Now, I
have seen some SS rolled all-thread which is fairly smooth, but I do NOT know
how accurate the lead is. I used some of that to make a hand-rotated
"rip-fence" on a bandsaw, and it was acceptable for that. But I'd never
build a CNC device with "fastener hardware".

True, ball-screws are too pricey to consider for cobbling "learning examples"
(unless you are Bill Gates?). ACME stuff is reasonable, but more costly than
the hardware-store fastener-class all-thread. But I'd never counsel to use
less!

Now, I will continue reading today's mail, and find several dozen other
members of this group will say otherwise? Lotsa luck! (Wish I had more of
that when I first began this home-brew CNC-stuff about '78!) Jan Rowland,
old troll


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