Re: Re: re:Re: Lead screws for ever...(plastic)

Chris wrote:I was going to use Kerk leadscrews, but after tracking

>down a local dealer last week I find out they are no cheaper than
>Ballscrews which surprised me somewhat....

>I may even resort to SS leadscrews and machine my own polyacetal or
>similar material nuts with anti-backlash etc. That'd do fine for
>what I want.

Chris,

Don't be surprised re: the kerks vs. ballscrews price. Similar
tolerances and machining needed. Similar markets.

But...

Something not often mentioned in the choice of ballscrews vs. ??? is
that ballscrews are EXTREMELY intolerant of dust/dirt/swarf/etc.!

While the "sliding" contact of acme (Kerk, and others)IS
somewhat "self-cleaning".


Re: making your own nuts... I mentioned in this thread earlier that
there is a BIG (exponential) increase in nut cost going from plain to
pre-load. I really think the place to "homebrew" (in the screw/nut
part of low cost CNC) is this area.

I also believe that you WILL spend more in time to save some dollars,
WHENEVER you are competing with a mass-produced product in a free
market. And that it is ONLY the ability to "de-value"(or "re-value")
the time by considering it "learning" or "fun" that makes this
equation work at all. I'm not saying that any of this is bad, just
that we need to be honest about the choices we're making...

Ballendo