Camera Alignment

There is likely also a consideration of perception. If the official stance is to help everyone who posts in Problems & Support, people know where to go and get an answer.

But, if you see loads of answers being given in Everything Else… then you can get rightly upset about YOUR problem which is ALSO in Everything Else not being answered.

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Good call

Thanks, these answers make sense to me.

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Exactly @jacobturner @bdm @natesland. And to be clear, I’m pretty bad at it. The actual support professionals have far more judgment and restraint. :wink:

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I don’t know that even I would say that. Not sure how to word what I want to say. It’s not that there’s no chance of any issue, just that I think, based on the majority, the odds are in favor that there won’t be any issue. Alternatively, Glowforge isn’t going to leave anybody unhappy with their purchase. So, in the end, where it matters, you’ll be very very happy with the machine.

So, @mpipes, I had all of 30 seconds yesterday evening to quickly put my square on the lid. I must say I’m surprised to report the lid itself is bowed. I laid the square front to back and noted a wobble. The square’s big so maybe I was touching the edge and didn’t see. So I put it across the lid diagonally back-left to front-right, ensuring I was on the glass only (not the edges). Definitely bowed. But my understanding, as you also stated, was that the lid itself was supposed to be flat. I didn’t get a chance to take a video, but mine is decidedly not flat.

Any other owners care to validate with their lid?

UPDATE on the above…
Yeah… Turns out my lid is flat. And my square? Not so much!

@dpruitt, regarding your post, I think you should only be a little concerned, but you should mostly be optimistic. As for the actual cause of my issue with this particular machine? Unknown at this time. I got it on Monday and I really haven’t been home since Sunday. :slight_smile: So WYSIWYG right now. Could be that my lid is warped (it is, but is that the issue?) Could be my camera’s not aligned properly. I have a couple more independent tests to perform before I put this in Supports capable hands. For example, I told @dan_berry and others that I’d test from another outlet. Not an unreasonable test. That’ll simultaneously rule out my outlet and my table. So I’ll be hitting that test as early as tonight.

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Digital equipment like this with a switch mode PSU should not be affected by power quality other than resetting if the voltage is too low for too long. You shouldn’t get random errors like missed steps. It would fail CE requirements as that involves testing with horrible power line spikes, flicker and brownouts.

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Thanks. Now that I see it, I recall you’ve stated that in the past as well.
Test: Aborted

OK< I am going to again anger the discourse gods by posting a vimeo video link ( made a clickable link in case). This on my PRU causes some misalignment in the bottom right (this was reported ages ago, and supposedly fixed in production? I recommended @Tom_A check if he was having this).

the problem happens around 3s into the video (it goes to slo-mo)

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Holy jog, Batman!

Unless the power outlet is, in itself, insufficiently grounded.

A SMPS can handle a little transient waviness on its own, but the rest of it needs a proper earth electrical ground to dump the excess. Also, SMPS in general are susceptible to RF interference, so if @Tom_A has the bad luck of being improperly grounded and near a major producer of RF… then that’d suck.

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Woah, kind a looks like there is something trapped in the x-axis belt. Can you see anything odd?

Heh. My luck’s not that bad. Definitely properly grounded. Was doing some electrical work in that room last year and popped one of those cheap analyzers into the outlets in there. And no major RF sources near (aside from my WiFi router).

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The other thing electrically… the line frequency. Not sure whether you’re more rural / urban or whatnot, but having an oddly out of whack 60hz power can also affect SMPS. You mentioned using one of those pocket testers; they don’t detect line frequency. Do you have a UPS that can handle the Glowforge to test it with?

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I don’t. It’s certainly something to consider, but I don’t think we need to pursue A/C as the cause of my alignment issue. We would have seen it in my first unit, and we didn’t.

Fair enough; just trying to provide some things to consider since we’all aren’t physically there like you are. :smiley: Honestly, I think electrically it’s a stretch, but one never knows. When I did a road trip through the US a few years back, I noticed the difference in even how Americans vs. Canadian rural infrastructure was coped with. Was kind of surprised.

Oh, I totally agree it’s something to be considered. And I do appreciate all of the great ideas from my fellow 'forgers! I just don’t want to go down an electrical rabbit hole when there are Occam’s razor level answers I haven’t had time to explore yet. :slight_smile:

I have no specific plans this 3-day weekend!!! HOORAY! So I’m gonna go through and test the things folks here have suggested, and report my findings to everybody and if there’s no resolution to be found, I’ll absolutely be contacting Support.

Frankly, I haven’t done that yet because my results haven’t been consistent. And I’m not going to bother them until I can give them something to work with. Hopefully something repeatable. But, if not, my results these past few days above have varied so wildly that that’s probably indicative of an issue in itself. I just don’t want to be a whiny bitchbaby that goes to Support without doing some basic troubleshooting myself, ya know? I’d rather whine to everybody else. :wink:

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A switch mode PSU only needs a ground for safety and RFI considerations. Other than that it it will be happy floating at half mains potential. There are many class 2 devices that work without ground. Class 1 devices with a missing ground still work but they have a half mains live chassis. Since the GF is in a plastic case with no external connections I don’t see why a missing ground would make any difference.

SMPS are not particularly succeedable to RFI. They are happy to produce it.

Not sure whether you’re more rural / urban or whatnot, but having an oddly out of whack 60hz power can also affect SMP.

Line frequency has virtually no effect on a SMPS. The first thing they do is rectify it to DC, perhaps with PFC.

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Brief update…
@mpipes
I edited my post above to reflect the fact that my lid is flat. Turns out my square isn’t!!! Who’da thunk it?!

While we’re at it, the way I figured that out for sure is I put my 2’ level on it to see if the 'forge is level. Well, not only is it level, but the lid is flat. :slight_smile:

@henryhbk
I checked to see if I had your little bump in the lower-right. I felt nothing. Perfectly smooth.

That’s all I can really do tonight. I assembled my new bike, but that’s about all the energy I have left. Sucks it’s gonna rain all day tomorrow. Guess that leaves me time to play with my Glowforge! :slight_smile:

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Line-borne noise – RFI and low-voltage transients created by high-current circuits – can couple by stray capacitance to the DC output, where it can disrupt circuits. Because the noise might be intermittent and beyond the frequency range of many measuring instruments, it can be hard to diagnose.

Higher harmonics of a 60hz power supply can fool control circuits. The more numerous zero crossings of higher harmonic frequencies can falsely trigger timing operations in the sine wave’s zero crossings.

A lot of SMPS regulate power through a combination of capacitors, OpAmps and PWM:
image

The SMPS PWM circuit compares the supplied 5VDC output to an accurate 5V reference so that an error-correcting feedback signal develops. This signal adjusts the relative ON/OFF durations of the DC converter, holding the output at the required 5V.

A SMPS can bridge a total power drop for periods of up to three 60hz cycles, but it relies on the filter capacitor (“C1”, above) to be fully charged to the design voltage.

So the TLDR; version is: high frequency harmonics = erroneously faster PWM pulsing = more constringent voltage regulation = lower output.

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O come on, you just made that up :wink:

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