Interesting Vector Cut Issue

[Joe Pelonio]

I was running a job to cut 1/4" acrylic from a file sent to me by the customer. Since I always had good luck with their files I didn't look at the details. I ran it and after 2-3 objects cut the laser sped up and cut the rest at about 3 times the speed I'd set it on (8).

I have never seen that happen, unless, of course, color mapping is set.

I checked that first, it was not, and all lines were black. Then I checked line widths. Aha, they were not hairlines. As I understand it the line must be under .007" or .5 point thick to cut. The letters that did cut were .217 points. The ones that cut too fast and only halfway through were .499 points. That translates to .00693......" thick. I suspect that being so close
to the limit caused some kind of rounding that confused my machine. Does the math sound right?


I since changed all lines to hairlines and it ran fine. Since I hadn't moved the material, nothing wasted.

[Pete Simmons]

I have always thought to be a cut hairline 0.003 was the max size.

[David Fairfield]

Good diagnostic there Joe, a less experienced person could have gotten hung up all day on that issue!

I keep a post it note in front of my drafting computer-- vector lines are .001" / 0.025mm Anything above that and my Epilog engraves 'em. Anything smaller than that and wierd things might happen.

Dave

[Angus Hines]

WOW learn something new every morning here. Didn't know the size of a hairline....LOL I always just use 'hairline' in the dialouge box. Now I know the value of 'hairline'.

[Richard Rumancik]

I have always thought to be a cut hairline 0.003 was the max size.

I thought that with the GCC LaserPro the "crossover" between vector and raster is .003". But I can't actually find it in the manual at the moment. The Jorlink/Mercury manual says to set the line width to the "thinnest" width in Corel to ensure that it vectors. This is not very specific, but the lowest default choice for pen width is "hairline".

A lot of threads have given people instructions to set line width to .005" or more to vector. This may work fine with some lasers but not necessarily all, so be aware that all drivers are not the same.

I would not use wide lines or hairlines anyway for my vector cuts. It makes it hard to see the nodes, connections between segments and just seems crude to draw this way. Usually I would set line width to .0001" or less for vector.

I haven't actually tested the .003" "threshold" recently so can't say for sure where the GCC will switch modes.

Also note that the GCC is designed as a metric machine, so when they provide "inch" values these are already approximations. I would stay away from the crossover point regardless of which laser I was using.