Re: [CAD_CAM_EDM_DRO] pcb router

Hi Tim, Bob,

Again, you've made some good points. I'm not advocating expensive
components necessarily, unless you can get them cheap surplus! I agree
that even threaded rod and home-made drive nuts can do a job for you.
My early experiments were with my Sherline (Dremel spindle).

I even bought a $70 (?) Sears XY milling table for a drill press (maybe
10 years ago). Plan was to attach steppers to it, and use it for
PCB's. The motors I had at that time weren't up to it direct drive.
And at the time, I didn't have an easy way to timing belt drive them for
some reduction.

I'm always going through surplus stores on the lookout for CNC parts.
That's where I've picked up my zero-backlash lead screws and round
ways. And lotts of steppers!

Bob and others:
I'd encourage the building of an entry level or low cost machine for the
experience! Dave Rigotti has a site with a PCB/engraving plotter you
can build.

And I posted pix of a design by Dan Mauch in "Nuts & Volts". Neither
Dan or I have any additional information on building it, you'll have to
find an old copy of N&V. This project was built using heavy duty drawer
slides!

Additional site:

http://www.hobbycnc.com/

Alan KM6VV

Tim Goldstein wrote:

>
> Alan,
>
> As our congenial friend at crankorgan points out, he is very successfully
> making PCBs without zero backlash screws or precision shafting on a couple
> hundred dollar machine. So we have living proof that it is doable is you are
> willing to accept some compromises. The main compromise would seem to be
> maintenance. John's machines will require replacement of the oversized
> delrin drive nuts to keep the lash close to zero. Another approach that
> would certainly get you up and milling PCBs rapidly and within the listed
> budget would be to get a Sherline with the 10,000 rpm option and concert it
> to CNC with some Geckos and TurboCNC. Should be able to have it up and
> running for about $1000 - $1200.
>
> Now don't get me wrong. I am a great believer in overkill. My plans for a
> PCB unit are to use the micron resolution 6" x 6" travel crossed ball XY
> stage I have with a Sherline mill column as the Z and a Fordom 15K RPM flex
> shaft as the spindle. Will have great accuracy and precision when I get it
> done. Only problem is the XY stage is a few thousand $$ piece if you don't
> find it surplus.
>
> Tim
> [Denver, CO]
>
> ----- Original Message -----
>
> > Hi Bob,
> >
> > More like $3-4K, sorry.
> >
> > I suggest you get some 12-18" zero backlash lead screws (ball screws),
> > some round precision shafting for ways and some recirculating
> > ball-bearing slides, and make one yourself!
> >
> > I found some surplus stuff several years ago, and am making a PCB mill
> > from them. See the pix for this list. In addition to the ways and zero
> > backlash lead screws, I've since collected motors and driver/PS modules
> > from three HP (II's and III's) LaserJet printers, so I have some low
> > cost drive for them also! The software, I wrote myself. You can get
> > TurboCNC, at the list:
> >
> > turbocnc@yahoogroups.com
> >
> > Here is a list for PCB's:
> > Homebrew_PCBs@yahoogroups.com
> >
> > Here is a recent PCB mill site:
> > http://www.epsilon-international.com/Products/products.html
> >
> > Hope this helps.
> >
> > Alan KM6VV