New material auto calibration

I can certainly see that running a full series of power/speed combinations before looking at what happened would be problematic, given the wide range of materials that could be used. However, couldn’t it start at full speed+lowest power, look at what happened, and then repeat that process with successively higher settings until it reaches the settings that result in a full cut, and then stop? That is how we would likely do it manually on something delicate.

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Even a generic “calibration category” dropdown list-style setup would be a nice starting point to let you see very quickly how different materials might work. Like:

“Hardwood, 1/8” thick" (calibrated for walnut, maybe?)
“Hardwood, 1/4” thick"
“MDF, 3/16 thick”
“MDF, 1/4 thick”
“Birch Ply, void free, 1/8” thick"
“Birch Ply, void free, 1/4” thick"
“Birch Ply, void free, 3/8” thick"
“Ceramic Tile, glazed”
“Copy Paper, 20 lb”
“Construction Paper”
“Cardboard, Corrugated, Double Wall”
“Leather, tanned, 1/16” Thick"
“Leather, tanned, 1/8” thick"

You could have a dozen or so test patterns setup ahead of time using a grid similar to the one pictured above, or set to cut at the edge as I mentioned previously, and users could adjust speed/power and save them as custom materials settings. I wouldn’t expect that, for example, the 1/4" hardwood setting would cut maple, walnut, rosewood and bloodwood the same, as they are all obviously different densities and grain structures. But it would be nice to have some generic presets like the ones above so that users could really dive in. If the purpose of the Glowforge is to allow non-technical people operate a highly technical piece of equipment, generic presets that might work for a lot of materials would be a smart and forward-thinking pursuit.

I’m not saying it will be fool-proof, but it would be pretty easy for someone already familiar with the software and the back end code to setup a series of test patterns using different power and speed settings. If the end user has to create all of these from scratch, that could make the Glowforge nearly as tedious as one of the $1600 Chinese 300mm x 500mm 50w lasers that are all over eBay.

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Lots of good ideas here, from my CNC router and 3d printer experience I’d say I want my settings to be mine but a public spreadsheet or another database where we can share our experiences with materials would be great. At a minimum, it would give you a ballpark setting to start with that can be tweaked.

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I wouldn’t mind using public settings as a starting point for my personal, locked and saved settings.

Seems to me that incorporation of the new Scio near infrared detector would give the cloud based definition of materials and real time detection necessary for an automated system to work. https://www.consumerphysics.com/myscio/

Glowforge 2.0 maybe :stuck_out_tongue: but there is a lot that can’t do, eg. Density and composite materials etc. Would be tricky

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Yup,
Plywood or anything covered with paper/tape…

Think they are on track with their bar code system.

I’m sure you’ve thought of this, but here’s my two cents for an “Auto-Calibration” process.

Starting with the slowest speed and power, raster squares across the surface. After each square, record average color values with the laser camera. With the addition of a (diffuse) light under the spoiler board, there should be enough contrast, even on tracing paper, to identify a through cut vs. engraving. Even on clear plastics the should be enough surface melting to cause a contrast (better if it’s masked).

Biggest issue is that with the server structure, the amount of additional data sent and processed on the servers. Extra bonus is that you could use the data to create special color pallets for each material, allowing designers to really see the piece’s approximate final coloring before even moving to the glowforge.

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One of the ideas we considered! Unfortunately material removal is nonlinear, so an amount of power that is insufficient to cut through would be sufficient to break through if you rastered with it. Think about it this way: with each pass, you heat up the material a bit, until the third or fourth raster line breaks through (even though the first one doesn’t). There are some other challenges too - it’s not easy to identify the grate on camera versus an unknown, arbitrary, engraved-on material.

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Business wise, are the coded materials expected to cost a significant amount more than materials elsewhere? For example, there’s a store I can drive to that sells acrylic sheets 12x24x.125" for $10-12 (the fluorescent glowing edge kind costs $12, all the regular colors cost $10). Should I expect that your coded materials will cost significantly more than their noncoded counterparts? Eg is the materials business expected to be a big profit generator with higher markups like Inventables, or is it being done just to make things more convenient for Glowforge owners and it won’t have any higher markup than a local retail store does?

We’ll let you know when pricing is available - I don’t have any info on that for you right now.

Now that Dan has given you his best answer. Just kind of wondering what answer you were expecting. If you were to ask the same question to the folks at Inventables, what answer would you receive? Don’t have a clue as to whether the materials and catalog sales are a big part of the business plan but I also wouldn’t expect an answer if it was. Still its apples and oranges. Not sure where you can find controlled quality, coded, masked, and laser tested material.

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Dude bro, where do you live? I’ve been pricing acrylic all over the country and never ran into as raw a deal as that. Call up that supplier and ask for the per sheet cost. That’s 48x96 standard sheet sizing. I’ve got a place in Minneapolis that will do a whole sheet for about 100$ at qaurter inch, about half that for 1/8th inch. Can get 16 pieces of 12x24 of that, or like, 16 12x20 and 4 12x16. About 25 to cut and would be about 20 to ship a sheet of 1/8th. About 40 for quarter inch, so you still come out ahead.

You could prolly do better locally and being able to avoid shipping charges.

Sawa: Nashville. I’ve looked around, and not had much luck finding it cheaper around here. What place are you buying it at that it’s $50 for 48"x96"? Pricing can really vary pretty wildly, a quick look on Inventables has them charging up to $30 for some colors of acrylic 12x24x1/8 inch sheets.

Rpegg: I know originally they were hoping to offer auto calibration, so I don’t think from the start the business plan included profits from material sales. When auto calibration didn’t work out that’s when they decided to do coded material from my understanding - I was just wondering if continuing along that path that they were offering the materials as more of a service to Glowforge owners (eg a feature of owning a Glowforge being low cost, affordable, materials that just work available direct from Glowforge) or if it was going to be more of a ‘let’s try to profit off the materials - they can only get Glowforge precoded materials from us so let’s take advantage of that’.

Even if the answer is ‘we don’t have anything to announced just yet’ (which is perfectly fine and understandable) it doesn’t hurt to ask. And thank you to Dan for answering so quickly, I had barely hit submit by the time his reply came in.

You bet. We’ve actually been testing custom plywood formulations recently - lots to do there. Pricing will probably come last.

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Where in Nashville if you don’t mind me asking. I am closer to Clarksville and hit up Jerry’s Artarama all the time. I grocery shop in green hills.
Glad to know there is another Glowforger in my area. I thought I was stuck in the middle all alone. .lol

This thread has prompted me to start shopping around for acrylic.

Just to confirm, it’s the cast, not extruded, variety that is best for laser cutting, right?

I’ve used Delviesplastics.com in the past and paid $7 to $12 for 1/8" 12"x24" plus shipping. Hoping to find a better deal.

I actually live just a few minutes away from Jerry’s Artarama. I only recently found the place though - after I ordered my Glowforge I really started looking at places I hadn’t been before locally to look for material to laser. Which is kind of funny because I’m looking at October at the earliest for mine, and I’m already looking at everything thinking ‘Can I laser that?’ I kept delaying, kept watching the Tested video with Dan over and over until I eventually jumped in - but it was after the campaign ended. I’ve actually been doing the same thing with the air filter - ‘Do I need it, I can put the Glowforge near a window in the garage, but it would be pretty nice to have it in right in the house as a self contained unit’. They haven’t shown the air filter at all, but once they do knowing me I’ll probably add one.

The ease of use was the big thing for me - while I’m comfortable with the software for 3D printers and CNC (I actually built a CNC with parts off the 3D printer - you’d be surprised how strong those plastic parts can be) I can’t really explain the CNC software to others. I’m really looking forward to just having family draw on acrylic, draw on plywood, and having the laser actually cut right along their drawn lines.

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What I am seeing is that there are trade-offs, and you can find a use for each type.

I had read recently (I think on these forums) that one smells considerably worse than the other when cut.

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I believe one is easier to cut(well a bit more melty, clear edges of cuts) and the other has more contrast in engraves(goes white)

But there are also the physical properties of the finished product to take into account. Does it need to be strong etc.

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