Re: Modifying an X-Y table - ACME - for fun and learning

Hello,

Nice to see a vigorous thread on something low-tech... And the
subject line about FUN and learning. Certainly the commercial
products work well and are a good choice, BUT...

They are a WHOLE lot of VERY useful cnc machines which don't need the
commercial grade stuff! Like this xy vise machine.

Moving on, I'm a bit confused about the reference below. Acme IS a 29
or so degree thread, and WILL "close up" (As Jan R mentioned) by
squeezing it (To use Sven's old idea, like squeezing the bun of a hot
dog). An Acme thread simply has wider crests and root spaces, when
compared to vee thread. This increases its strength.

A SQUARE thread would behave as Dave mentions...

BTW, carefully made, these xy vise machines can easily repeat to .001"

(That's with the 1/4-20 threaded rod, NOT the original screw)

Hope this helps,

Ballendo


--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude"
<davemucha@j...> wrote:
<snip> Since ACME is not a taper, jsut squeezing the nut does not

> automatically mean a tighter fit... ergo some backlash
> compensation. I think I will look at adding a nut for a tandem nut
> unit so that the origional will be used with the addition of some
> sort of backlash compensation.......
>
> Dave