Would it be better for the machine to engrave from point 0 onwards instead of going to the end of the design towards point 0 ?
My point is, when engraving, you get the “dust” of the engrave towards the front of the machine so if it’s engraving from the front of the machine backwards, the dust is “ruining” what’s already engraved! RIGHT ?
If the machine goes the other way round, it would engrave on top of the dust making a less messy engraving finished product ?
Am I wrong ? Sorry, but it’s just something that intrigued me since day one
The ability to switch directions has been requested many times. Many other machines have this capability. I forget the reasoning for the GF choosing to engrave from front to back, but engraving on top of the “dust” could also introduce additional variance in the quality of the engrave.
I’ve gotten better at cleaning up the residue, so it doesn’t seem like a big deal anymore, but it would be nice to have the flexibility of changing engrave direction.
I decided to run a little test anyway…for science.
So I set up a little circle engrave, going in one direction, on messy thick draftboard. Ran the engrave, then turned the circle around 180° and engraved over it again, so the laser was burning up all the crap and resin that had been deposited over the open engrave from the first pass.
Want to know what happened?
About what you’d expect…the resins were fused into a glass-like substance in certain spots, giving a really lousy looking uneven engrave.
It’s really hard to capture with a camera, (sorry, my close-up was a little too close I guess), but the dark patches and spots that you can see in the image are glassy, smooth and fused…they are not the same texture as the rest of the engrave.
My conclusion based on this run is that the folks at Glowforge know exactly what they’re doing by running the engraves from bottom to top, depositing the soot and resins harmlessly on top of the already engraved areas. At least the detritus can be brushed away doing it this way.