Cheap & simple height-probing

[bsdphk]

Those of you trying to produce fine features by isolation routing may find this interesting:

http://phk.freebsd.dk/CncPcb/

Enjoy,

Poul-Henning

[harryn]

That is a neat idea. Actually, it is quite useful for not only PCBs, but a whole lot of areas such as engraving. The board traces are cut quite sharp compared to some I have seen.

Thank you for sharing that idea, and welcome to cnczone.

HarryN

[cwiliam]

really interesting hope to see more

[dhookings]

Well I think that is quite brilliant. In conception, and, from the picture on your web site, in practice. I gave up on isolation routing because I could not guarantee producing smd pads at 32thou centres. You have there 4thou lands at 20thou centres.
Unfortunately I use different control software, and my brain clouds over when I see C code.
Mach3 uses G31 to probe, and stores the coordinates in #2000 to #2005. I should be able to work out where to substitute those and hopefully the rest of the syntax would parse ok.
I'm going to give it a go, anyway.
Any pointers would be appreciated.

Dave

[sounddog]

this is my first posting so sorry if there are any errors...

Reply to DHookings,
I'm in the same boat, C-Code makes my head hurt..

I currently make pc boards on my Mach3 driven mill with much success, but recently have discovered board thickness variations (insert grumpy sound here!).

A floating head spindle could work, but my Wolfgang spindle isn't threaded to accommodate the foot that I have (long story, could send pictures to clarify).

Any development ideas?
Anything I can do to help??

Cheers!
Mark

[casainho]

Originally Posted by bsdphk Those of you trying to produce fine features by isolation routing may find this interesting: http://phk.freebsd.dk/CncPcb/

Good work! and thanks for sharing ;-)

[alenz]

Has there been any further work on this? This could be a VERY valuable tool. Too valuable to just let the development go dormant. I would love to help, but unfortunately it is beyond my current capability.
al

[BobWarfield]

Very clever!

Best,

BW

[bsdphk]

Originally Posted by alenz Has there been any further work on this?

I have made a couple of PCBs using this method, you can see one of them here:

http://ing.dk/uploads/society/content/201.png

The method has a lot of potential, but there are some ugly corners that need to be cleaned up, before it is ready for "prime time" use by people who cannot tweak C-code at will.

Right now, it works well enough for me, that I don't spend a lot of time on it, and since I only make a few PCB's a month, that is unlikely to change fast.

If somebody wants to adopt the project, I'll happily hand it over, along with a long email with random notes and observations...

Poul-Henning

[prosys]

All,

Can anyone give me any clues as to how to compile and get the code running (Ubuntu 8.04), I get an error pretty early in teh compile that I can;t get past...
make plt2g
cc -g -O0 plt2g.c -o plt2g
plt2g.c: In function ‘stitch’:
plt2g.c:1038: error: ‘list’ undeclared (first use in this function)
plt2g.c:1038: error: (Each undeclared identifier is reported only once
plt2g.c:1038: error: for each function it appears in.)
plt2g.c:1038: error: expected ‘;’ before ‘{’ token
make: *** [plt2g] Error 1
peter@peter-mini-CNC:~/Code$

From looking at the code the probelm appears to be either an include thats gone wrong (though there are not other errors shown, or the code is out os synce` with teh header from the web page that I downloaded...

Anyone happen to have a pre-compiled binary for the EMC2 release of Ubuntu 8.04 ?

[charliex]

in plt2g.c change

#include <sys/queue.h>
to 
#include "queue.h"

make sure you downloaded the queue.h from the website

you may or may not have to deal with srandomdev(), which srandom(time(NULL)) should take care of.

[prosys]

Thank you, that got me further (and yes I did need to put the srandomdev fix in) and now I'm looking at another compile error...

Seems that the hypot function does not exist in my math.h libraries...I presume.

peter@peter-mini-CNC:~/Code$ make plt2g
cc -g -O0 plt2g.c -o plt2g
/tmp/ccn6ddff.o: In function `sort_seg':
/home/peter/Code/plt2g.c:340: undefined reference to `hypot'
/home/peter/Code/plt2g.c:348: undefined reference to `hypot'
/home/peter/Code/plt2g.c:354: undefined reference to `hypot'
/tmp/ccn6ddff.o: In function `draw_vectors':
/home/peter/Code/plt2g.c:539: undefined reference to `hypot'
/home/peter/Code/plt2g.c:570: undefined reference to `hypot'
/tmp/ccn6ddff.o:/home/peter/Code/plt2g.c:630: more undefined references to `hypot' follow
/tmp/ccn6ddff.o: In function `do_file':
/home/peter/Code/plt2g.c:1210: undefined reference to `emit_gcode'
collect2: ld returned 1 exit status
make: *** [plt2g] Error 1
peter@peter-mini-CNC:~/Code$

I created a simple "result=sqrt(x*x+y*y)" substitute function that seems to satisfy that requirement but now a call to "emit_gcode(j) fails since emit_gcode is not defined anywhere., though there is a prototype for it in plt2g.h

You can probably tell my coding is very rusty...