So today I was working on a few projects that involved proofgrade plywood, proofgrade draftboard, and the white marbled acrylic from Inventables.
My usual choice for settings for Inventables materials is to just choose the most similar proofgrade material and go with that. I’ve never been let down. So, when I got to the part of my project that uses the marbled acrylic, I just chose proofgrade white acrylic from the menu.
Then, I cut a piece from PG plywood, then PG draftboard. Here’s where the weird part comes in. I put the Inventables sheet back in the GF, and went to the app to select white acrylic again as usual, and it was already selected! Keep in mind this is after I’ve done some plywood and draftboard too.
The Inventables marbled acrylic comes with a barcode sticker on it, not a QR code like PG materials. Is it possible GF is remembering I associated their material with that barcode?
Did the proofgrade materials used in between acrylic jobs have complete QR Codes? Did the second acrylic cut use the same file as the first one? I haven’t been able to figure out the rhyme or reason, also haven’t tried, but I have seen materials retained through multiple lid openings when there wasn’t a proofgrade QR code to wipe them out.
I would be very surprised of the glowforge was remembering random bar codes.
Highly unlikely, but not impossible. However, QR lookup is read-only, outputting a 6(?) character code. That code apparently uses a lookup table in the GF backend to determine the appropriate settings for that particular batch of PG. UPC barcodes and QR codes require different decode libraries as well.
My new, more plausible explanation is that since the Inventables acrylic was the first proofgrade material used in the session, it became the fallback default when a material wasn’t recognized. So when I put it in after a PG job, it used that new default.
So it looks like they are putting lot codes into the QR data, but for at least the two samples I checked there was no difference in the settings. That’s not surprising, given how onerous it would be to characterize each lot of material and incorporate the data into the toolpath compiler. GF put the hook in (as engineers are wont to do) but I wouldn’t hold my breath over them ever leveraging it.
