If camera alignment worked then it would be easier. Put in a blank, press the magic button. No need to make a jig. If it doesn’t work like that then yes the traditional CNC methods are needed.
And those would be much easier with a couple of limit switches. Without you are suggesting fiducials but they need the same accurate cameras.
Also I agree that when you manually position and scale something you should be able to get back to that state by entering numbers. CNC equipment should not rely on manual dexterity with a mouse.
I use an L shaped origin jig at 0,0 on my CNC router and micro switch limit switches to make thousands of parts all the same. I also have edge finders if I need to index of the work piece. I added limit switches to my CNC lathe because it came with none. It was expected that one would touch off the blank but that is no good when you want to make a thousand parts the same in multiple sessions.
Well the good thing is that they have 2 cameras. I think the head camera is going to end up being very important. Its the one thing that makes me feel a lot more comfortable about accuracy moving forward.
I think the weak link in this whole thing is the camera being attached to the lid. It throws in so much inconsistency that theyre having to deal with. If there was instead a camera mounted on each of the side panels, it would give them a much more stable platform to work on.
Now that I think about it, if they wanted to, they could use the head cam to calibrate the lid cam at any time. Stick in some calibration sheet with particular features, use the lid cam to detect the location of the feature, send the head cam to see if its where it thinks it is, report back the discrepancy, rinse, repeat. It could build a nice distortion matrix to deal with camera warp on a per unit basis this way.
I don’t know how accurate the honey comb is but the lid cam could photo it and the head cam could go around looking at specific points of the mesh to see if they tally and make a warp compensation matrix from that. It would be very slow though uploading thousands of images to the cloud.
It makes me wonder how the 3D auto focus will work on curved objects. If it has to process images in the cloud it would have to scan the object with head camera and laser pointer and upload thousands of tiny images.
I saw that, and Ive had to deal with that on a few cuts of my own and was pleasantly surprised with the outcome! Im wondering if something has a pretty crazy topology, how well it would be able to keep up with it changing so rapidly. It would have to move that lens up and down really rapidly. Guess its something we can put on the testing docket =)
Correct. When I tried to put a 4" circle design on a 4" cork coaster I was a hair off (or the camera was). So when I pulled the piece there was a ring around the artwork. Had I been cutting the whole thing, the circular cut would have taken care of that but because I was using a pre-cut coaster I told the GFUI to ignore the cut line. Unfortunately when I tried to enable the cut line and ignore the engrave the app errored on me and I couldn’t do it. So i have a little ring of cork showing on the edges. That’s okay for home, but it’s not okay if I were making these for sale.
This is what I was assuming was the case from the beginning. The head camera being an optical edge finder could be exceptionally accurate.
edit…
OK, great. That has been part of the plan from the beginning. Maybe I didn’t assume it after-all. It seems like I just heard Dan say it and then remembered it.
Here’s a post that former user spike posted when I mentioned that I hoped the head camera would be used like an edge finder…
Set your artboard to 20x12 and it will always snap to the same location when uploaded.
We believe delivering your machines, as promised, ASAP, is more important than anything else right now, and that’s where all of our development energy is focused.
I dig the jig-with-fiducial thing, though.
Eventually we’ll compensate for any drift in the lid camera - we have some tricks up our sleeve there that we haven’t talked about.
It isn’t feature drift. Accurate positioning with the cameras has always been promised. Dan even mentions it in the Tested video above and phrases it as if it already works.
8 . Optical Alignment
The dual cameras align the laser head with the frame, with your design, and with your material. Glowforge realigns with every cut and engrave, adjusting timing and position, so every print comes out perfectly.
Yes they need to continue to work on the optical, yes they need to give us an absolute system, no they don’t need to delay anything adding the absolute/cartesian system. It can come as ongoing software development. The theme of this thread is feature drift.
We seem to be going round in circles, but why? If it can locate the corners to sub kerf accuracy and translate the artwork to match then why do you need to push it against a jig and why do you need a fixed 0,0. It could be defined as the bottom left corner or your workpiece, where ever that lands.
I get that @Dan, and in fact have my AI set to always default to a 12x20 document, however, since the piece isn’t rigidly held in place, nor is the bed, it’s not absolute like it is on my 3D printer or CNC mill.
Except if you’ve removed the material and put it back in between operations the material isn’t exact anymore. I ran into that problem trying to re-engrave my centering ruler when the tick marks didn’t engrave. There’s just enough play in the crumb tray to shift it a few hairs (that’s a technical measurement in this case thicker redheaded hairs, not the finer blonde hair ).
If the head camera will be able to do edge sensing, wouldn’t it be reasonably easy to detail, then, a corner of a jig as 0,0 for the purposes of batch processing? Designate the work space to be the size of the jig, and the upper left corner is always 0,0. That would give consistent results provided the jig is consistently oriented in the bed. It wouldn’t even have to be in the same spot of the bed each time, so long as ‘up’ was always up.
in this case thicker redheaded hairs, not the finer blonde hair 
).