Homebrew PCBs

Hello all,

We've visited this before - the Silhouette cameo vinyl cutter that 
Mike used to directly cut traces in copperclad. Unfortunately, I was 
not able to get his technique to work very well, but now I'd like to 
use the machine to "print" traces using heat cured electrically 
conductive one-part epoxy. What I'd like to do is convert the cutter 
to a plotter. As it is now, the vinyl cutter uses its proprietary 
software to cut (or sketch, using a pen holder) around the edges of 
the traces, which is fine (sort of) for isolating the traces, but not 
what I want here. What I'd really like is to use it like a plotter, 
drawing the traces down the middle of the designed trace. The width 
of the trace could be controlled by using different needles on the 
dispenser or controlling the air pressure.

I'm willing to rip out the electronics and make my own stepper 
drivers, but I'd like to know what software I would use to run the 
converted machine, presumably using some form of HPGL. Does anyone 
know how this would be done? I really don't want to reinvent the 
wheel here, but I'm willing to do a bit of soldering if someone could 
point me in a reasonable direction. Thanks for any help or insight!

Mark

>drawing the traces down the middle of the designed trace. The width
>of the trace could be controlled by using different needles on the
>dispenser or controlling the air pressure.

Mark, why not output the HPGL in 'multiline' format, with fixed pen width?

>I'm willing to rip out the electronics and make my own stepper
>drivers, but I'd like to know what software I would use to run the
>converted machine, presumably using some form of HPGL. Does anyone
>know how this would be done?

Kcam4 is free and good for controlling a standard stepper driver.
Cristian

I'll look into it - thanks. I know very little about the specifics of 
HPGL, but it sounds like the way to go, here. The physical stepper 
driver is very easy since these are very small steppers. I'll have to 
pull the pcb, but I wouldn't be surprised if I could hack into the 
pcb and use the on board stepper drivers.

Mark

At 02:22 PM 2/27/2013, you wrote:

> >drawing the traces down the middle of the designed trace. The width
> >of the trace could be controlled by using different needles on the
> >dispenser or controlling the air pressure.
>
>Mark, why not output the HPGL in 'multiline' format, with fixed pen width?
>
> >I'm willing to rip out the electronics and make my own stepper
> >drivers, but I'd like to know what software I would use to run the
> >converted machine, presumably using some form of HPGL. Does anyone
> >know how this would be done?
>
>Kcam4 is free and good for controlling a standard stepper driver.
>Cristian
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

i would have to strongly suggest linuxcnc.org
as an active user this is the best supported most configureable
machine controller out there and its free :)

-- 
jeremy youngs

Unfortunately it doesn't look like it's free anymore.


--- In Homebrew_PCBs@yahoogroups.com, Cristian <bip@...> wrote:

> 
> Kcam4 is free and good for controlling a standard stepper driver.
> Cristian
>

No, but it isn't that expensive, either. Another (free) alternative, 
as has been mentioned before is Linux and linuxcnc. You would have to 
become familiar with Linux if you haven't used it (I haven't), but it 
should be pretty easy if you are only using it for one program.

I just ordered a 3 axis controller on ebay ($42 USD including 
shipping), though I think I could use the parts from the on-board 
controller to make my own controller, especially if I use the parallel port.

Mark

At 02:51 PM 3/3/2013, you wrote:

>Unfortunately it doesn't look like it's free anymore.
>
>
>--- In Homebrew_PCBs@yahoogroups.com, Cristian <bip@...> wrote:
> >
> > Kcam4 is free and good for controlling a standard stepper driver.
> > Cristian
> >
>
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

On Sun, 03 Mar 2013 16:35:04 -0500, you wrote:

>No, but it isn't that expensive, either. Another (free) alternative, 
>as has been mentioned before is Linux and linuxcnc. You would have to 
>become familiar with Linux if you haven't used it (I haven't), but it 
>should be pretty easy if you are only using it for one program.
>
>I just ordered a 3 axis controller on ebay ($42 USD including 
>shipping), though I think I could use the parts from the on-board 
>controller to make my own controller, especially if I use the parallel port.

As a note culled from the CAD/CAM group.  Please be aware that the
chip/chipset used in the boards can be a limiting factor.  Some chips
cannot be pushed all that close to their limits.  Almost all (if not
every one) of the chips/chipsets do NOT tolerate removing the load
(stepper) from the chip with power on.  It generally blows the output
in the chip (requiring either replacement of the entire chip or the
driver for that channel, if separate).  

You need to be aware that connectors used to run the board to the
stepper need to be as robust (read: lock in place) as possible, and
the wires need to be reasonably flexible (wiring from the connection
to the stepper will flex, so you don't want that to break).

That said, I think, (without any kind of data to the contrary), that
these boards will work well within their limits (NO overvoltage, NO
overcurrent, NO disconnects).  The only boards/drivers that I know
about that are as rugged as possible are made by gecko, and are the V
series (vampire.... Mariss has a sense of humor).  Even then, the
warranty is outstanding.

What I use (because I'm thoroughly cheap and had the chips) is an
L297/L298 chipset with jumper settings for parameters and optical
isolators for step and direction.  I haven't blown any of them, *but*
I have been very careful with what I've been doing.  Roughly 35 volts
and about 2.5 amps maximum, no behavior compensation, so not the best
in the design.

I'm doing a parallel port if I mess with a controlling PC, a custom
program (to be written) using an XMEGA otherwise, and for a full blown
solution, an FPGA hardware pulse generator (it works, but I need to
see how good it is, implemented in the simulator).


Harvey

>
>Mark
>

Thanks for the input, Harvey. This little vinyl cutter uses very 
small steppers (1.7" dia x .6" thick) that draw about 500ma at 24 
volts. The original  board uses BD6395 driver ICs which are rated to 
1.2 A at 28 volts; The board I bought will do at least 2.5 amps, so 
it shouldn't be a problem.

Mark

At 06:46 PM 3/3/2013, you wrote:

>On Sun, 03 Mar 2013 16:35:04 -0500, you wrote:
>
> >No, but it isn't that expensive, either. Another (free) alternative,
> >as has been mentioned before is Linux and linuxcnc. You would have to
> >become familiar with Linux if you haven't used it (I haven't), but it
> >should be pretty easy if you are only using it for one program.
> >
> >I just ordered a 3 axis controller on ebay ($42 USD including
> >shipping), though I think I could use the parts from the on-board
> >controller to make my own controller, especially if I use the parallel port.
>
>As a note culled from the CAD/CAM group.  Please be aware that the
>chip/chipset used in the boards can be a limiting factor.  Some chips
>cannot be pushed all that close to their limits.  Almost all (if not
>every one) of the chips/chipsets do NOT tolerate removing the load
>(stepper) from the chip with power on.  It generally blows the output
>in the chip (requiring either replacement of the entire chip or the
>driver for that channel, if separate).
>
>You need to be aware that connectors used to run the board to the
>stepper need to be as robust (read: lock in place) as possible, and
>the wires need to be reasonably flexible (wiring from the connection
>to the stepper will flex, so you don't want that to break).
>
>That said, I think, (without any kind of data to the contrary), that
>these boards will work well within their limits (NO overvoltage, NO
>overcurrent, NO disconnects).  The only boards/drivers that I know
>about that are as rugged as possible are made by gecko, and are the V
>series (vampire.... Mariss has a sense of humor).  Even then, the
>warranty is outstanding.
>
>What I use (because I'm thoroughly cheap and had the chips) is an
>L297/L298 chipset with jumper settings for parameters and optical
>isolators for step and direction.  I haven't blown any of them, *but*
>I have been very careful with what I've been doing.  Roughly 35 volts
>and about 2.5 amps maximum, no behavior compensation, so not the best
>in the design.
>
>I'm doing a parallel port if I mess with a controlling PC, a custom
>program (to be written) using an XMEGA otherwise, and for a full blown
>solution, an FPGA hardware pulse generator (it works, but I need to
>see how good it is, implemented in the simulator).
>
>
>Harvey
>
>
> >
> >Mark
> >
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>