Re: 4-AXIS FOAM CUTTER

Hi Coert,

Thanks for the descriptions. What else gets done to the foam you cut
for signs? Or is the foam the finished product? I'm only familiar with
the foam used for insulation in homes! Looks like this "wing" foam is
finer, denser stuff?

What software have you been driving your steppers with? I could see
simple linear cuts being done with just rate generators, but anything
more involved would need software!

5 machines! Do you have a web site where you've posted pix of your
machines?

Alan KM6VV

Van Der Sandt Coert wrote:

>
> Hi Alan
>
> I have been working on getting the foam edm machine to cut for about two
> years. I believe that I have it cutting just about OK now (within tolerances
> for foam). I originally started this project to cut foam cores for RC
> airplane wings, but as time went by I started to realize a lot of different
> applications for the machine. I have cut quite a few signs so far as well as
> some shapes for interior decorating. None of this on a commercial level
> though (maybe someday) I have started the building of a 3 meter by 3 meter
> by 1,5 meter high machine, with this I hope to do some bigger signs etc.
> Some specs on the machines :
>
> Number 1 :
> This is about the 5th version I built. Originally I built it from old
> printer steppers and linear slides etc. It has now been upgraded with
> industrial belts and slides etc. The stepper controllers were bought from an
> electronics supplier to the industry as surplus. Steppers are from old
> floppy drives run at half step to give 400 steps/rotation. Control is by
> step/direction pulses from the lpt port. The linear increment per step is
> 0.1021 mm which is fine because the wire cuts away about .7 mm of foam.
> Cutting dimensions are 1,5 meters wide by 1 meter deep and 220 mm high.
>
> Number 2 :
> This machine is my best attempt at a professional build with properly
> machined parts and industrial standardized belts, pulleys, linear slides and
> bearings etc. Step controllers are 4A per phase and BIG stepper motors (I
> don't have the specs with me now) 3,1A current draw run in half step mode
> (400 steps/rotation). This time I reduced the linear increment per step by
> driving the carriages via a belt reduction (4:1) from the steppers. The
> machine hasn't cut yet but should be completed soon. The wire will
> ultimately be heated electronically (does anyone have a circuit for this?)
> and cooled by ex RC electric ducted fan turbines where it is exposed. Again
> control is by step/dir pulses from the lpt port.
>
> I hope I didn't bore you all to sleep.
>
> Cheers
> Coert vd Sandt
> Universe Administration (Unix)
> Dimension Data
> Alexander Forbes Business Unit