strange different depth of engraving in one graphics

[Martin Safranek]

Hi everybody,

now im starting play with engraving on my G Weike Z6 because i have problem with my Laserpro X axis servo. I tried few tests but everytime have problem with different depth of engraving in engraved letters. Letter parts are bit deeper engraved and i dont have idea why. Any suggestion ?

Thank you for help.


Martin

engraving.JPG

[Bert Kemp]

could be just soft spots in the grain of the wood. what wood is it?

[Martin Safranek]

Bert,

thanks for hint but it cannot be because in red marked places is engraving deeper in rowmark plastic sheet too... Wood is Beech plywood. It must be something else.

Martin

[Matt McCoy]

I would double-check your alignment.

[Bill Carruthers]

Looks like it's the horizontal areas that are darker/deeper. Try slowing down to about 200-300 mm/sec and maybe set your scan gap to around .085 - which is about 300 dpi. Might help.

[John Noell]

+1 on Bill. 500 is really fast and I suspect slow build up of power as the head comes across to 'scan'/engrave. I see inconsistent depth (including too shallow in vertically narrow areas) when using too much speed.

[Glen Monaghan]

It appears to be linked to the amount of "on" time on a horizontal scan, aligned with the crosses on the 'T's and tops/middles/bottoms of the "e" and "s" (you didn't mark the middle of the "s" but the issue is also present there, though not so pronounced). I seem to remember seeing previous threads with this issue though I don't recall what their solutions were...

[Dan Hintz]

Long horizontal cuts allow the tube to fully ionize the gas for a strong lase, a downside to glass tubes... the suggestion of reducing the overall speed is a good one.

[Martin Safranek]

Thanks for all hints. ill try it today. im already ordered 90w tube which will be better for engraving than 130w.

Martin

[Martin Safranek]

Now it is much more better... Speed 300 is ok but power under 20 % is needed for perfect result and its too low for tube. 90 w will be ok. Thanks to all for help.

M

[Rich Harman]

I think it is a software issue. There is a clear correlation between the length of the pass and the power being output. If it were a matter of the tube needing time to build power then you would see variation along the length of the pass. It looks like the program is changing the power output based upon the period of "on" time - and not doing it well.

You might be able to avoid the issue by converting the text to a bitmap.

[Ivan Pavletic]

This type of engraving I'm having with GoldenLaser, Chinese machine. No matter what I tried to do, it always has those thick lines. By slowing the speed you can make some improvements.
After buying Trotec speedy 300 Goldenlaser is mostly for cutting and drawing lines