Re: plasma setup-leadscrew vs. rack & pinion + software

go simple and cheap.

Plasma is not super accurate, postioning anything better than 0.0005"
is not needed. working back, that is 2,000 steps per inch. a 200
step stepper with the Gecko is 2,000 step per rotation. so a one
rotaton per inch is a good target.

rack and pinion are the easiest way to go, both for the cost and
installing simplicity. if you want, make your stepper mount with
enought room to change gears for higher and lower ratios.

regarding software, Master5 for Win98 offers the best interface bang
for the buck as regards importing drawing files.

TurboCNC offers the lower cost computers new life. 486-66 runs it
well.

Dave

--- In CAD_CAM_EDM_DRO@yahoogroups.com, nvlibby@c... wrote:
> Hi, I'm in the process of building my first cnc plasma unit. I was
> hoping someone could answer 2 questions I have .-First the specs
on the
> table:
> I'm basically constructing a plasma table big enough to handle
4'x8'
> sheet/plate (5'x10' overall?).
> I'll be using g201 gecko drives to microstep 2 ) 542oz/in bipolar
nema
> 34 steppers(thanks dave@ camtronics)
> At this point I'm trying to decide ( based on economics) the best
way to
> move the gantry, so my 1st question is- with this type of
> setup,(plasma), what would be a more effective/effecient power
> transfer-gear rack & maybe pulleys, or a lead screw,( acme
precision
> lead screw perhaps?)
> I'm trying to get the best torque/speed ratio,(isn't everybody!) -
And
> based on best option, can anyone give some sizes/pitch,ect
> .
> (Also I realize that to do a lead screw setup, ball screws would be
a
> better option , but right now funds are limited,put it into the
> electronics& motors)
>
> 2nd question- I've seen alot of software options out there,any
> suggestions for plasma? I have 500mhz computer, win98se, TurboCad
v7, &
> corel trace ( packaged with turbocad program for scanning images to
> vector files)-Any hints on cost effective ( for now) programs?
>
> I'm sorry to be long winded, I've tried to do all the homework
without
> bugging anybody, but at this point in the game -this group is a God
send
> & I really appreciate any help offered-thanks