Re: Digest Number 2

Gar <garfield@...> wrote:

Subject: Just On-board

Wanted to say hi to all, and specially to those who've helped me in past,
such as Dan Mauch. Hi Dan. Hi the rest of yous CNC guys from RCM. Also
special thanks to Bill for "janitoring" the group (that's a term of respect
on some other groups I've been part of, so take it as a compliment B).

My ongoing projects:

CNC'd Sherline's (the usual lathe and mill stuff)

4' X 8' X 24"+ CNC bed router for alum/urethane foam contour routing for
eXperimental aircraft and automotive stuff. Guides built around surplus
Thomson shafting, bearing, and ball-screws.

Both powered by Dan's small and large motor-controllers, respectively,
along with the usual AHHA Artisan & PC interface, etc. All the step-motors
for both of the above I also got from Dan. Am I a Mauch mooch or what? Heh.

Love to learn about and eventually get into CNC'd hot-wire styro cutters,
small-scale EDM, and FINALLY discover with the group some encoders that
would make nice inexpensive (<$100/axis) linear DRO's feasible. Dang, why
doesn't HP make some of their linears with the right resolution! Their
rotary's are perfecto. Grumble.

Anyhoo, look forward to seeing this grow. Anyone else keen on largish
gantry-style routers?

Gar Willis
Merced, CA

[I've been dreaming about a large gantry router for a while now. It seems that
surplus parts exist that would facilitate the construction of one of these,
but no
one source seems to have all the parts I'd need, and I'm hesitant to invest in
a pile of parts that might not ultimately be the right size. Any words of
wisdom
on the best parts to look for? I'd like it to be heavy-duty enough to cut
parts out
of wood- foam doesn't appeal to me much, although I realize that urethane
foam prototyping board makes good patterns (but is brutally expensive.)
I'd be
interested in discussing the pros and cons of other machinable materials.
I've
got a pile of surplus I-beams that I was thinking of using as a
super-structure,
because the compaint about most of these gantries is lack of rigidity in the
traveling beam. But these things are heavy, so I'd have to find
correspondingly
bigger motors, I suppose. The main reason I'm considering building instead of
buying one of these (aside from basic skinflintery) is because the
available units
I've seen never have much z-axis- they all seem to be made for sign-makers.
But
with extra z-axis comes another problem- how to find end-mills long enough to
reach? And even if they can extend far enough, are they going to be stiff
enough
to work? Has anybody dealt with this, and come up with a solution? How far
along
is your router project- any pictures yet?]

Andrew Werby


Andrew Werby - United Artworks
Sculpture, Jewelry, and Other Art Stuff
http://unitedartworks.com