Accurate pocketing?

I just deleted several of my explanations. The reason being is that although in my gut I believe there may be a way to increase the resolution beyond 256 using the laser focus, I couldn’t come up with a use case that works. The Glowforge doesn’t handshake back to the servers as far as I know between passes and the controller is just too dumb to do it locally so can’t figure out how it might work. BTW: A response from Dan on another thread. 1000 dpi resolution with variable engrave is not the same thing as saying 1000 dpi engrave.

1 Like

power*passes

The X/Y positional accuracy is 1,000 dpi. It’s hard to describe the z-axis in DPI, which is why we specify power levels, but the laser has z-axis power adjustment of 255 levels, times the number of positions of the lens (which escapes me now but is much more than four). In practice how these combine to achieve z-depth precision depends entirely on the material you’re using. You’ll get more depth precision out of delrin than tissue paper.

9 Likes

When I placed my order one of the main reasons was the 3D capabilities. I obviously misinterpreted the marketing but I still truly don’t know what the machine will be able to do in practical terms.

Will I be able to make an acrylic box with mitred corner joints?
Will I be able to bevel, chamfer and round the edges?

The statement “Engrave complex, three dimensional curves with 1,000 DPI resolution. " Implies I will be able to do these things. I don’t know how anybody could interpret it otherwise but comments in this thread seem to imply I am expecting too much. It is not as though I am totally naive. I have made a living designing and selling FFF 3D printer kits. Maybe that is why I thought Glowforge would be able to do these things but with a Z accuracy of only 0.05” I don’t think it can.

Will it be able to make smooth slopes or will they be stepped like FFF parts? If so what is the step size?

You say experimentation is required to get the correct depth but why can’t the Glowforge cut a series of test pockets and measure the depth with its camera? Given it can cut pockets and given it has a camera that can measure material thickness I can’t see why it can’t do one followed by the other.

1 Like

It depends on the material.

It may be possible, but is not part of the feature set at release.

It sounds like the product may not fit your needs - you can email us at support@glowforge.com and we’ll get you a refund ASAP if you’re concerned. You can then wait for retail availability, try it out, and see if it’s right for you before purchasing.

1 Like

So, on another thread, this question was asked;

@dan, can you confirm whether this sort of depth work will be possible with the Glowforge? It looks like back on Oct 15th you indicated it would be able to do it;

Does the issue @palmercr is referring to mean that the smooth bevel will not be possible, or just that the accuracy of the curve will vary depending on the material being used?

(By the way, the quotations are being used for reference… not trying to make accusations of false advertising or anything… just looking for clarification)

1 Like

The accuracy of the curve will vary depending on the material being used.

Yes but what is achievable with ideal materials like acrylic and Delrin?

There are no straight answers here. Can we make smooth Z curves in these materials?

Maybe he can correct me if im wrong here, but Ive seen this somewhat discussed in other threads (ive been asking the same questions), it will be possible in acrylic, less so in wood. To further clarify his answer, he stated in another thread that it would be a much smoother curve in homogenous materials(like acrylic), than in something where the density and consistency changes throughout the material (wood). He put up an early sample of a beveled cut here:

You can surmise that because this is a laser, and makes no physical contact with the material it is cutting, that getting accurate 3d portrayal of a design is going to vary on a case by case basis. If you are looking to get a consistent 3d cut through multiple materials you might want to pick u something that cuts physically, like a cnc router/mill. (or have both like I do! gives you everything you need!)

I already have three CNC routers, a CNC lathe and many 3D printers. I am adding a laser cutter as there are some things it is better at and a lot of things for which it is much more convenient / easier to use / faster. There is a significant amount of labour involved in operating a CNC router.

I don’t want to cancel my order because in another thread I heard somebody else from the UK lost hundreds of dollars in exchange fees when he got his refund. I also still think it will still be a good machine for the price even if it can’t do 3D stuff. The compact form with built in cooling and filtration, good quality low maintenance optics, quality tube with small spot size and the pass through are all good features.

I do think the advertising has been misleading though but I still don’t know for sure as Dan’s answers around this topic are not to his usual standard of clarity. Perhaps I just have to wait until I get one myself.

1 Like

Although @rpegg linked to this topic, it was a quote from @dan at the end of the topic. Here’s easy link to top post and picture goodness since this is relevant to here.

By the way. Just realized discourse requires a bit of precision when linking and quoting to get the full experience. Realized that if there is a space in front of the new line that has the link, there is not quote. Just the link.

1 Like

@palmercr I understand and share your concerns, since I am also looking for all the information I can gather on precision and cut quality. I think your questions are interesting and would be completely reasonable to ask if the Glowforge was available in its final form.

However, the advertising can only be considered misleading if it ends up having been wrong. I don’t think anyone outside of Glowforge (and maybe not even inside Glowforge) really knows what it will be capable of doing and with what precision. As of a very short time ago they did not even have their final custom power supplies available, and I am sure that the state of the software lags behind the state of the hardware. It has too. The beauty of the situation is that they can collect live data from running machines and make incremental adjustments to software over time.

Perhaps @dan is being circumspect in part to make sure they are not promising something they can’t deliver, but also because he just does not know yet! Everyone makes mistakes, optimistic inventors and innovators aim high, and if the end product lives up to even 80% of what they originally wanted it to, I will be satisfied. (and no, I don’t know how to measure that :slightly_smiling: )

2 Likes

Correct - we know what the HW will do and what the SW can order it to do. We don’t know how the material will react to it yet, because fine tuning of all parts is required before the final answer is known.

1 Like

Is there a location on the forum/google drive/etc for the beta/pre-release folks (and eventually the rest of us) where they can enter engrave/cut depth data on: material type, greyscale, speed, power, etc into an excel-like database so that cumulative knowledge on proofgrade materials can be stored for everyone to be able to use?

I :revolving_hearts: Greyscale!

3 Likes

Not for pre-release users. This is the only forum we have. Beta users do though.

1 Like

I guess someone could add a new category to the link repository. It is open to all for editing and adding. If someone were to do different cells for, material, source of material, power, speed, and user name who added, that might be useful.

Prob have to wait till after release for it to be useful. Not sure if the beta guys are allowed to talk about that stuff.

We’re working with our legal & safety team on a way we can facilitate the sharing of information on materials that don’t come from us.

12 Likes

Since some folks have received their units, has anyone tried pocketing into a proofgrade material? I saw Dan’s photo from earlier in this thread. I wanted to see if any other users have pocketed yet.

I’d be curious to know if it works well into wood. How deep the pocket can be (.5 inches?)…

I’m trying to decide if it would be better to build in layers, or maybe use my Shaper for the pockets and cuts, then into the GF for engraving… thx!

Well on Proofgrade you can’t go 0.5" deep for a pocket without doing a fair amount of carving in the honeycomb :stuck_out_tongue_winking_eye: since the wood is 1/8" thick… So if you need 0.5" thickness either multi-pass on solid non-proofgrade or stack some proofgrade and pocket into that.