first test: 90 degree - 1 problem round corners
angle >90 degrees - 2 problems - round corners and while the blade is trying to turn, also trying to lift the vinyl
in any movement the offset must be calculated, and machine should make smal circle with same radius as the offset, this will turn the blade in to the new direction, and then can continue with a next cut
how i can do that?

Nik,

Not that I ever actually learned how to use the likes of autocad, it would seem that you need to explode your drawing, extend the lines by the offset and reconnect the path with a radius equal to your offset. So if I am following what your saying if I were to look at a cut vinyl sheet I should see tiny circles at the outside of each direction change? I have some vinyl logos coming in a day or two, sure hope he didn't harvest out the scrap as I would like to see this. I am pretty sure when I worked at a laser and waterjet place about 10 years ago the software took care of this automatically as it converted the vector graphics to g-code or whatever they were using, I do know that a broken path would ruin a thousand dollar brass sheet in a second.

Just thought of this option, using a software like signcut to generate the HPGL file then convert the HPGL to DXF, process through lazycam .... Well I didn't say it was the shortest distance between two points but neither is the cutting path.

Kristin

is it the offset included in HPGL file?

Again I am not a user of this but I am pretty sure the offset is generated in the software, including the loops you mentioned, bigest hurdle is trying to convert hpgl to dxf although I think I found a source at Guthry software for a trial converter you could give a try with and it's only $30 USD for a single license if it works. Let me know how things turn out, I might just mount a swivel knife in the mill and have a wack at it or build a small table just for cutting vinyl.

Kristin

yes, you are right, the offset is included, i just generate one hpgl file with signgo, then i open it with corel draw, on all corners there is an arcs, so.... may be this is the way

Nik,

Great, I think if you can open it with Corel you can save it as DXF so problem solved I hope. Let me know how you make out.

Kristin

PS- just downloaded signgo and can't find how to export as HPGL, it was the full ver not the lite.

job done
it is tricky but if you are patient you can cut some letters
when you install signgo, go to your windows control panel and add printer HP > HP-GL plotter
then properties on that plotter and set output to file
then in signgo when you press cut, you have to set output device your hp-gl protter, the rest you know how to do it

the only problem is that i didnt find how to set the path for output file, now is going in windows/system32, but it is not so bad

now with this offset, the blade is turning much easyer on the corners, i think that this could be a nice plugin for mach3, so any drawing cuold be cut straight with mach, the attachment is a test with offset 1mm, so you can clearly see how should be, the file is opened with import in corel draw

Nik,

Interesting might be my system but I am seeing 2 quarter round segments on each turn and they look like it would swing a weird path, it's getting late so I am not going to let it keep me awake. Can you post the g-code for that one, I'd like to load it up and run it on the desk just to see what it looks like. Perhaps some of the others that do sign cutting will pop back with a comment also, I can see this as useful for the occasional one-off things I want to do and not pay the big bucks to the local printer for their setup charges.

Kristin

there is nothing wrong with your system
here is the g-code for same thing, but this is with 1mm offset, it is too much for regular blades