Accuracy question


#23

Not really. I’m generally working in a relatively narrow range of materials when I’m doing this - 3mm to 3/8". The 0,0 point I’ve created is always going to be the same - the camera’s perception of material aligned with it is what is affected by the material thickness.

So my 20x12" artboard defines (effectively speaking) the 0,0 offset for my actual project. If I’m an inch up & over from the lower left corner in Corel, then the GFUI has it an inch up & over as well and every design I do will show up there as well.

The trick is getting the camera view to align close enough to drop it at the inch up & over point on the material. That’s where everyone’s challenges are coming from. GF says that we can expect what I’d now call the 1,1 location on the artboard might be .75-1.25 in either up or across position - a quarter inch off but it could be a quarter left or right so actually up to 1/2". (I’m assuming the 1/4" stated potential margin of error is + or - but it could be they mean it is really + - 1/8"…I set my expectations conservatively and have been pleasantly surprised as I achieve better accuracy :slight_smile:️ ).

So when I want precision I place a targeting reticle at the upper or lower left corner of the artboard. Then I set the GFUI to 200% magnification (after setting the material height if needed) and move the drawing so the reticle lines up with the 0,0 on the GFUI’s ruler (for an upper left reticle). I’m always pretty close - one or two clicks and that’s entirely based on whether I drop the blue artwork bounding box (Ctrl-A in the GFUI) exactly on top of the ruler line or if there’s a hair of ruler showing.

Of course once it cuts the resulting red (magenta?) lines are not precisely aligned with the cut image on the physical material. That’s when you trust your instruments and not your seat of the pants sensibilities of what it “should” be because your eyes (camera) are fooling you.


#24

I’d propose pouring a small puddle of fast setting resin(I’d use PU ) into the divots, then drop the oiled feet of the crumb tray down onto it for a permanent fixed position.
This assumes the feet are tapered of course !


#25

Not sure that would help. The ability for the bed to move out of position is a relatively theoretical thing. Can it? Yeah, because it’s not locked down. Does it? Not really from my experience and I get 2 mouse (or arrow) clicks repeatability in GFUI camera view vs actual material placement pretty reliably.

I think it matters more to the people wanting thousandths of an inch repeatable accuracy of the camera vs material imaging.


#26

That’s encouraging, so thanks.


#27

I agree with @jamesdhatch. Alignment on materials is one of the least concerns I have. Barring the odd calibration routine or unusual lid camera behavior, I generally think of 1/8" or smaller accuracy for eyeball/zoom positioning. Learning how material rests in the bed and how the crumb tray holds I do not experience for my use cases a negative for how the Glowforge aligns.

The crumb tray is pretty still in the divots, and flat, and even the edges of the honeycomb can be used as a positioning guide.

Again, all this is dependent on one’s individual needs and use cases. In my experience, I just figure all this in my work flow and it gets the job done.

And you’ll definitely want to keep your crumb tray removable because of thicker things like cutting board possibilities.


#28

What is in my mind is to fix the position of the crumb tray so that I can reliably anchor a jig to it for using the pass-through slot prior to the software for it being implemented.
I’m looking to cut lots of long, narrow, but curved pieces in veneer, repeatably.
John


#29

I’m not trying to cauterize individual neurons, but some things that are reasonable to engrave (e.g. penils) have a relatively small margin and I’d like the machine to have enough accuracy (not necessarily today, but when those software improvements are in) to visually center things and ensure I don’t go off the sides. I pretty much get that now, there’s just a small left-right skew, but vertically it’s perfect.


#30

Add me to the people who have not had the crumb tray move. I guess it could move… Mine mashes up against the front door (!) and might wobble a little if I put pressure on it But the divots and the feet fit together pretty well, even if it’s not a positive lock.