Not certain this will help your understanding of the process in general or GF’s implementation in particular, however, Russ at SarbarMultimedia has done a video featuring the ramp function as used when engraving using a CCL. Not sure if it is this one or this one.
Thanks for the help! I will check out the videos.
edz
Basically they’ve cut the piece in at least two passes. The first pass is a (or the first few passes are) deep engrave(s) and the second pass (or final pass) is a standard vector cut. The first pass engraves a channel that clears a path for the laser to come in and do a vector cut.
Think of it this way…
Let’s say you had a 1" thick piece of wood, let say it’s about the size of a business card (3-1/2 x 2"). Let’s also assume that we know the Glowforge is capable of engraving this particular wood 1/4" deep. If you were to “engrave” the entire piece of wood, you’d reduce the thickness to 3/4". The new dimensions would be 3-1/2 x 2 x 3/4". If you were to repeat that process, you could take it down to 1/2".
If your goal was to end up with two pieces that were 3-1/2 x 1 x 1/4", you could do the whole-surface engrave one more time to get it down to 1/4" of thickness. Then you could come in and do a vector cut to split it into two.
Or, if you wanted two pieces 3-1/2 x 1 x 1" (or close to that) you could engrave just a channel for the final cut, instead of engraving the whole thing.
If you don’t want to move workpiece and with the 1/2" of focus range of the head, the maximum depth you could cut would be 1/2" + whatever thickness you could normally cut with a focused beam.
For instance, if the laser is powerful enough to cut/engrave 1/4", you’d be able to get through 1/2" + 1/4" for a total of 3/4". You’d do one 1/4" engrave at the top of the 1/2" of focus range, then a second 1/4" by bringing the focal point down 1/4", then do a third 1/4" by bringing the focal point to the bottom of the range and doing a third engrave (or a cut).
… at least, I think that’s what they’re doing - pretty clever!
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Honestly, we didn’t plan to be able to do that, but with some careful experimentation we figured out settings to make it possible with Proofgrade hard maple & walnut. Likely can do it with other materials too. The secret is going slow and removing a wide area of material on multiple passes so the lower-focused lens can do its trick.
It is 1/2".
Going thicker than 1/4" is very slow, so I wouldn’t plan on doing it regularly.
The slope is, if my recollections of trigonometry serve, <2 degrees.
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Theoretically true but as yet untested. 
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That agrees with my experience cutting with an Epilog machine.
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I remember taking a class in HDR photography from Terence after he had taken that photo. Glad to see that he is working to protect my investment in Glowforge.
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They do seem to have snagged some talent, haven’t they? 
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Nice. I love watching things actually happen.
Seeing the end product of 3d in the December QA, imagining that with pass-through and seeing people getting refunds when asked for I upped to the pro a week ago.
You just re-confirmed that choice watching that, thanks.
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I agree with you completely. We only have so many hours a day so we have to decide what we want to do with that time.
It’s like owning a classic car. It may be beautiful and you have fully-customized the engine and interior, but you are going to spend a lot of time tinkering with it to keep it in top shape. (Most old car guys I know say they spend more time working on their cars than actually driving them, but those guys say that is what they love about the hobby). Do you want a cool car to drive around, a cool car as a project, or something in between?
I sell 3D printing services on the side. I could have built my own printers for a lot less money, but I spent the money for prosumer machines. Why spend that extra money? Because I’m being paid to print things for people. They aren’t paying me to tinker with my printers. Or to get a new printer and spend a week or two building it and dialing it in. I get lots of projects from people who were fed up with my competition, who constantly have printer issues.
This is why I purchased a Glowforge. I don’t want to spend weeks researching how to rewire a laser with shoddy wiring, figuring out a cooling system and then having to tune things. I could if I wanted to, but I’d rather spend the time making things and spending time with my family.
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Well said!
Quality well built printers/lasers/etc take care of themselves (and you), while labors of love pay off with great satisfaction.
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I believe your trust in the Glowforge will pay off. It is extremely reliable. Dialing in designs and tweaking settings to do projects without tying it up for hours can be a problem, but that is all relative, as you know from the extruder world.
I do believe it will pay for itself in no time.
I have three clients that are patiently waiting for it to arrive. One project will be a pretty big project for the GF - engraving around 500 small acrylic blocks for a college class reunion. (all will be identical) Luckily, they don’t need them finished until February 2018.
The other two clients are developing prototypes that will be a combination of laser cut parts and 3d printed parts. If I don’t have the GF by the end of August, (I think I’ll realistically be early to mid-October, since I ordered in the middle of the initial campaign). I’ll have to farm it out, which will shave off some of my profit. BUT, this is why you always mark up costs and add extra time to any paid work. And I don’t want the first thing I do on the GF is work on a project. I need some time to get to know the ins and outs of the GF.
I also backed the Wazer watercutter on KS last fall. If it ships on time (which I doubt, because it’s a Kickstarter) I could possibly cut the parts for the prototypes with it. In reality, I realize both will arrive the same week and something will come up to prevent me from having time to play with either one.
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Isn’t that the way it always goes 
Is this design file and settings available on here somewhere? I would like to study it so I can make similar, thanks!
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I came back to see if there were any replies and the link to the design I was referring to is gone! What happened?
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What kind of wood was this and how thick can we go? I need to make parking signs that will be exposed to beach front elements. I want thick wood that will withstand the salt and beach air. And be deep 3D like this amazing picture! Also, PLEASE give me the settings to plug into the machine(material, and cut etc). And where do I purchase this 1/2 inch (I’m guessing) wood from? I would love to get at least 1/2. Spell it out as much as you can. Some of us are not as advanced as you geniuses 
Figure the people reading this are dumb as the wood we are buying. You guys are awesome! Thanks
I’ve done it so far in maple (has to be solid wood, not ply) and the machine has this as stock settings in the GFUI so just trust it (obviously test, use the LPI to burn deeper). I am betting some other hardwood (say oak) would work. Obviously you can stain/polyurethane after to weatherproof it. I’ve done engraved red oak signs with shellac and they’ve lasted years. I just used basic red oak boards from Home Depot. While I have engraved cedar back in the PRU days, to describe it as smoky would be a gross understatement and it would likely burn in a deep engrave.
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I’ve tried and tried to do a 3D engrave and mine never turns out right. I don’t know what I’m doing wrong but would love to learn if someone is open to guiding me.
So one quick way to check that it’s working is to use one of the many internet 3D depth maps and just try it out (always a cool demo). I include a bunch of files in this chain of posts: