I once worked in a firm where the power supply was so bad, something like the small dormitory size refrigerator turning on would freak out the UPS units. That was also still the days of CRT monitors before LCD, and some of them were so sensitive you could see the image on screen slowly wave left to right, like watching a hula dancer. It was just barely visible and enough to give you headaches by the end of the day.
You’d have to have a particularly bad connection to the grid to have a noticeable issue with electronics. The voltage coming through the outlet is typically an average (RMS) value of 115-120v which means the voltage actually peaks at 162-170v. To see 130v RMS means a peak at 184v and that’s only 8% over 170 so still within what’s deemed acceptable by the power company. Electronics are all designed around this flexibility and anything that’s particularly sensitive should have the means to handle it built within. Once in a while you get mains power that’s outside of normal though and that’s when you get problems.
I’ve considered that possibility. But I’ve no way to test the power quality. I wonder if the Glowforge has any such sensors in it by which the company can make such a judgement. I haven’t confirmed but if I remember correctly that circuit has the Glowforge on it all by itself.
Modern digital equipment should not be affected by power line quality other than perhaps resetting if you get a long brown out. Switch mode power supplies work with a wide range of input voltages and provide a stable output to everything downstream.
Having said that it is a very odd effect. The head must travel at a varying speed or the data must be sent to the laser at a variable speed because some parts of the line are stretched and some compressed. What I find inexplicable though is when it does the next scan line it follows almost the same pattern of disturbance, but it slowly evolves as the Y axis moves. And if it does each line in alternate directions that means the disturbance is reversed.
I think a fine grid engraved at different speeds would be revealing.
I completely agree. I’m just not going to blow anymore quality material testing this. I’d use cardboard but I don’t think the resolution of cardboard would be enough to reveal the issue. I’ll check to see if I have any scrap wood left though.
That’s exactly what I was just testing.
I started w/ the TARDIS to replicate the issue. Got wavy vertical lines.
But I ran into a really weird thing… I can’t engrave the grid! It’s an svg and it will only let me score or cut!!! If I switch to engrave it just disappears!!! What the heck!
I believe you’re exactly correct. They’re probably just lines. No matter. Using a gif grid instead. Surprisingly-long engrave. Another half an hour to go.
The full TARDIS has been ~3.5" tall. I decided to kill my first grid at ~2.5". Those grid marks are ~.4". I’m doing another grid now at ~half that spacing.
I’m not sure how much one can tell from this. For me, there’s too much optical illusion around the intersection points. The separate lines worked better for my brain.
Just going to put this out there, that it’s going to introduce another quirk to any analysis since it’s a digital photograph of testing lines that will no doubt introduce lens distortion.
Should be able to throw a square on it and verify easily.
The vertical lines seem to curve smoothly in between horizontals but seem to often change direction where they cross the horizontal. No idea what that means.
