Re: [CAD_CAM_EDM_DRO] A little bit of help; Always works!!!

> I am still undecided what to do whether to buy a ready made
>CNC like the Taig milling machine or to retro fit one myself.
>Personally I would rather build one myself, get a small milling
>machine and you know do it myself. But I am worried about the
>electronics of it and the software sides of thing!! How have people
>done this?? Is there any literature that anyone knows of like a step
>by step guide to converting a machine?? Any companies that supply
>the electric gubins??? And the software?? I start getting lost in it
>all?? Should I just buy on of these small CNC machines??

Anthony, a CNC machine has 3 parts: mechanics, electronics, and
software. What choices are best for you depend on how comfortable you
are with each. There are of course complete packages, but I think
many of them that are in the hobbyist price class may have serious
compromises in one of the areas, so in the end you'll end up doing
some system integration to upgrade things.

Mechanics:

First you need to decide what size machine. For just experimenting,
the sherline and taig size machines are good. People will loudly say
they make real parts on them, some apparently even in cottage-industry
production settings, but of course they have to be small parts. If
you want to make larger parts you may want to look at things like
the RF45 mill, or possibly the shoptask 3-in-1 (although there are
some serious compromises in that design.)

Then you need motors and mounting hardware. If you don't have a lot
of machining experience, or would rather get on to the rest of the
project, then buying a machine that is available with premade motor
mounts is a definite win. You can for example get a sherline with the
motors already on it, or with mounts for standard 23-size steppers.

Electronics:

For simple machines this primarily means stepper drives. You can get
low-powered drives (2amps/phase) in kit form and assembled at various
prices. Many on the list use Dan Mauch's (www.seanet.com/~dmauch).
For larger machines there are things like the gecko drive modules
(www.geckodrive.com). Of course you have to add a power supply to
those. If you want to minimize wiring, outfits like Ah-hah (hope I
spelled that right) have complete enclosed boxes that you connect to
the computer, wall outlet, and motors.

Software:

Again, it depends on what you are comfortable working with. There are
solutions for dos, windows, and linux. The windows drivers that work
well include a custom hardware box and are a little more expensive.
The linux system called EMC works well, and continues to evolve, but
really is best for someone who has used linux or unix before.

And of course there are outfits that will happily sell you a machine
tool, motors, drive electronics, software, and maybe even the pc to
run it. If the package is within your budget it may be a good way to
get started. Generally, you can with a little work make most
components from one source talk to another, so you can eventually
upgrade the lacking parts of a package.

Chris

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
http://www.mdc.net/~stratton
NEW PHONE NUMBER: (617) 628-1062 home, 253-2606 MIT