PG White Acrylic not cutting all the way through

Hello everyone,
I recently ordered a batch of white acrylic PG from Glowforge and it does not cut all the way through on PG settings (after the latest systems upgrade PG settings have not been working on my machine for the most part). I then dropped it to 170/full before it cut through all the way. I have the acrylic masked, my lenses and mirror and bed are all clean, and yet it does not cut through consistently on designs. Gone through a lot of material this way…could really use some insight…

Below is the image with the latest problem:

That it cut through equivalently shaped spaces in other spots on the design makes me wonder if it wasn’t flat - if the acrylic bowed up there the cut could have been out of focus and therefore weaker. I’ve taken to using the honeycomb hold down pins on everything!

For these pieces, it’s possible the cut is most of the way through and if you take an x-acto knife (or equivalent) and run it along the side that did cut it may drop out the last little bits! Worth a shot at least

That’s it’s PG acrylic using PG settings, once a staffer gets here I believe they will offer to replace the material at least.

It’s a cute sign!

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Thank you so much for your response :slight_smile:
The material was entirely flat, and that was the second cut that turned out that way. While I would certainly hope that a staffer would offer the new material, that has not been the experience I have been offered in the past with similar issues :confused:
As for using an exacto knife, it creates rough edges when pulled from the rest of the design even after cutting so that is a no-go as well. It only cut this good on the second one because I flipped the design to a mirrored reflection (ironically the machine has started to cut some designs with more script better this way). Nothing makes sense…

It does, but a few seconds with a lighter will smooth those right out!

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Won’t that create the melty edges that happen? This is an item I am selling so all edges have to be uniform and smooth - not the glary/melty thing that I have seen happen

And I would just like the machine to work reliably each time - especially with PG materials - without me having to go through extra steps that might damage the materials…so I am frustrated this continues to happen

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I have not found that to happen - if it were a huge area maybe, but on edges it just smooths flat

I understand your frustration. It’s not a problem I’ve had personally, but I see the posts on here and a small portion do seem to have had weird reactions after the last update.

I can guarantee that they are working on it on the back end and you will see results, because that’s what has happened with any of the other hiccups. Sadly that’s the downside of buying a machine from a baby company and running a business with it. WAY cheaper than the equivalent industrial machine, but it’s still growing and changing so it might not be as reliable.

Not reliable at all to be honest and the cost of wasted materials makes me wish I could return it and buy an industrial machine…the reliability would save me money and clients…

Do you check that all the inner cuts are complete before lifting out the design (I use a piece of blue tape) ? As long as you don’t move the work piece or the file in the gui, you can run the cut again and same the piece. I’ve never noticed a problem with the edges after doing so, nor have my clients.

Nope. – search YouTube for “flame polishing acrylic edges” to see numerous examples and tutorials.

My experience is that there’s “flat” then there’s FLAT . A very common gotcha is that even a visually undetectable warping of the material can cause issues. If you tap anywhere on your material and hear a click or an hollow sound, it’s not FLAT .

Your best bet is to cut out a dozen or so Honeycomb Bed Holddown Pins and use them to make absolutely sure your material is firmly secured. I cut out a few from draftboard scraps leftover from various jobs – you cannot have too many of these. :sunglasses:

My cutting success skyrocketed when I adopted these as part of my workflow.

Best of luck!

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Another thing to consider, the entire sheet may have been flat but as you cut it, the stress from cuts can cause the cut parts to bow. For designs with intricate inner parts like this, it might be good practice to ensure you cut those portions first, while the sheet is mostly intact. You can do that by ordering the cut operations by using different colors in your design software. The GF-specific palette is posted here, I shared it just the other day if you want to search for it (that would just prevent having to re-order in the GF UI, which only takes seconds…)

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The GF can be a great machine–but it’s not designed to be an industrial scale machine. So indeed you may be better off with another.

BUT to help avoid “wasted” material–before you move the sheet after a cutting job, check each piece that is cut out to see if it wiggles/moves within the kerf. You can feel the difference between one that is fully cut and one that is not. If not all are free, close the lid and print the job again (ignore any etching).

And the sheet may be flat to start with, but there are internal stresses in most materials, and cutting can release (or in acrylics even create) those stresses and cause the material to move slightly (this is true for any machine). So if pinning from the outside alone doesn’t work, maybe you can split the job into two cutting steps, load both, ignore one, and after the first is done, take those cut out pieces off the board (not moving the sheet) and then place more pins on those internal edges, then ignore that first job, and cut the second.

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I cut one to three pieces a day, basic items, nothing that calls for an industrial machine. In addition, reliability should not be exclusive to an industrial machine. Given the price tag of this “hobby machine” it should be able to cut through PG materials with the settings provided in the software. In addition, prior to the recent software upgrade the machine did cut through PG white acrylic more consistently than it currently does.

While I appreciate advice on how to get the machine to work, insisting that its constant glitches are to be expected is less than helpful and only serves to confirm my belief that many of the people offering advice in the forums are in some way sponsored by Glowforge to try and calm the large number of users who are wildly dissatisfied with the quality and reliability of the machine.

I will contact the support team and hope I get something more helpful than “cut the handy measuring tool design” response that they typically put in email and official forum responses.

Sorry that my environmental conditions may vary from yours, and yours may vary from the location GF did all the testing for PG materials to determine settings.

Humidity does affect lasers and materials. Material properties can change with temperature–coefficient of expansion–most materials shrink in the cold and expand in heat. Dust or residue on the lens or mirror will affect the laser.

PHYSICS is what is causing many “constant glitches”.

No, I don’t get any paycheck or kickback from GF. Nor does anyone else that is not Staff on this forum that are sharing their experience & learning and are gracious enough to try to help others along the learning curve.

I sometimes have had problems too. And sometimes I’ve lost jobs, too. But I learn to verify my material is flat, sometimes slow the speed down from PG a bit, and always, always check a cut before I remove the sheet. And clean the lenses.

I do wish GF put a big Asterix next to Proof Grade about Physics. But it’s still damn good >95% of the time. But the learning curve can suck.

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When a machine stops cutting PG materials accurately and reliably after a systems upgrade performed by Glowforge than it is not a matter of a learning curve - it is a matter of a systems problem that has impacted more people than just me.

As for the “sponsored” feel of the responses, when nothing but a rosy glow style response about Glowforge (in response to multiple forum posters in fact) is given in response to every frustrated GF user’s complaints of the machines glitches and malfunctions then the credibility/motivation of the respondent is inevitably going to be called into question.

I will be leaving this thread now.

I have an idea… since you know from the first post, that dropping the speed by 10 clicks or so makes it cut reliably… DO THAT.

Lasers are precise. Very VERY precise. You know what isn’t as precise? The materials they cut and engrave. Every piece of wood is different. Every piece of acrylic is different. Maybe not by much. But enough that settings on one piece might work fine and another one might not work at all. Or in your case, in MOST of the piece it works. In SOME of the piece it doesn’t. I just don’t understand people that can’t figure out simple stuff like “turn the speed down a few notches and it works fine” and just want to complain.

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I see you’ve emailed us about this and I’ll be working on it with you there, so I’m going to close this topic.