What the GAP

[Trey Tull]

I was working on some focusing tests with the fiber and noticed there is a small gap where the line doesn’t finish.

I opened EZCad and drew a 5mm box. Adjusted the power and set it ablaze. This is what I got.
405211

In the bottom left corner ( image rotated when I uploaded it) the lines don’t touch. Does anyone know what setting this would be?

Thanks!
Trey

[Kev Williams]

405217

both of your open lines are too short, meaning the laser is firing too late AND shutting off too early, so you need to adjust the "TC" values (below the speed/power/freq section)

The numbers to mess with are the Start TC and Laser Off TC numbers-- note that the Start numbers can be positive or negative, the Off numbers must be positive. I haven't done this for awhile and can be a bit confusing but I think you need to lower the Start numbers and raise the Off numbers, but honestly, I'm guessing ;)

I would change the Start numbers first, lower whatever it already is by 50, then run the square- check to see if either line end gets longer or shorter. You want longer, so if one gets shorter, then raise the number by 100 and test again. If it's still too short or too long, adjust in increments of 10 or 20 until it's real close.

then change the Off numbers, start by increasing its current value by 50 then test--- same rules apply, if the line got shorter, then decrease by 100...

The "Polygon TC" setting tweaks your corners; too much delay will over-burn them, not enough delay will round them- yours look very good, almost perfect.

WHEN you get the numbers how you like them, BE SURE to hit the "apply to default" button at the bottom-right, or they'll just go away. ALSO, any saved jobs will come in with the OLD numbers, so remember that!

[Trey Tull]

Thanks Kev!! Its funny that I'm just noticing it after month of using this machine. I'll play with it over the weekend and report back.

[Kev Williams]

If you don't have an EZcad manual, google and download it, towards the end they get into these settings- not that they all make sense, but it's a good read as far as getting a better understanding of how to make adjustments, and of how the mirror scanning process works :)

[Vasek Matyska]

I got same issue and was very happy to find out the solution with start and end tc values.

I got a question. When I find best values fot start and end and polygon tc, is it usable for any speed value? Or when speed changes, start tc must change aswell? I guess so, just want to confirm

Thx!

[Kev Williams]

To be honest I'm not sure if speed is a factor, but could be. But it's easy enough to test by running a 3" square at 50 and 8000 speed and check the corners :)

Thing is, those mirrors are always moving, and much of the time 'vibrating' is a better description. Even when drawing a square, both mirrors are almost always in constant motion; except for when a true horizontal or vertical line is passed thru the centerline of the lens, both mirrors must move to draw a straight line (to compensate for the lens bending the laser beam :) )

[Vasek Matyska]

I know its easy to try things like this, but I have so many ideas in my head and so many things to try but so little time with tha machine :(

Thought start/end/polygon and speed values depend on each other, but I think I should listen to more experienced one ;)

Kev, are you saying that you found one ideal setting for those TC values and never changed them?

[Trey Tull]

I just changed my values and got it super close under a 16x loop but couldn’t make them come together. Thanks again for the help Kev!