|
FatCow posted:Auto-darkening welding helmets are always blocking UV. When they darken it's just a LCD screen going black to block the visible light. I loved this video of an HDR welding setup, where you're not looking directly at the weld through a heavily smoked glass, but rather at the video from helmet-mounted camera. https://www.youtube.com/watch?v=gtTdiqDqHc8
|
#
?
Mar 1, 2021 17:54
|
|
|
|
| # ? Jun 6, 2024 01:55 |
|
|
https://twitter.com/BBCWorld/status/1366434574302138374?s=20
|
|
#
?
Mar 1, 2021 18:15
|
|
|
Elviscat posted:So there's an old piece of equipment called a stroboscopic tachometer, that worked by cranking a numbered dial on a calibrated strobe light until a piece of rotating equipment looked stopped, then you look at the dial and that tells you how fast it's going. Isn't there an issue using single phase leds around rotating machines since they look stopped when their moving at a multiple of 60 hz?
|
|
#
?
Mar 1, 2021 18:20
|
|
|
some people get excited about work https://i.imgur.com/yMVBPNl.mp4
|
|
#
?
Mar 1, 2021 18:28
|
|
|
Kith posted:some people get excited about work It's cool when they let the big trucks bring their kids to work
|
|
#
?
Mar 1, 2021 18:29
|
|
|
Phanatic posted:I loved this video of an HDR welding setup, where you're not looking directly at the weld through a heavily smoked glass, but rather at the video from helmet-mounted camera. This is amazing. If the latency was low enough this would be unbelievable to weld with, using the output as your vision.
|
|
#
?
Mar 1, 2021 19:11
|
|
|
BgRdMchne posted:Isn't there an issue using single phase leds around rotating machines since they look stopped when their moving at a multiple of 60 hz? Probably! I have a fancy dancy LED flashlight that controls brightness by changing the on time of the LED (how fast it blinks) and it's fun to stare at rotating machines and make them "speed up" or "slow down" (apparently) by changing the brightness setting on th light. I haven't found one that syncs up and appears stopped though. titty_baby_ posted:Its not even 8am and ive learned something new today. Djing turntables have a series of dots around the rim and a pop up light to use in calibration, where at certain speeds the dots will appear stationary. Its the same concept but instead of a blinking light its the rotation of the rim that does the "blinking" I forgot I have a turntable that does this. Stack Machine posted:Huh. I was just thinking along the lines of "I'll just reach down and adjust the workpiece on this totally stopped lathe", but steam explosions sounds even worse! I've seen one used once, outside of training, somehow the org I was doing testing broke all their phototachometers (just a laser that gives a digital speed readout based on reflections from some tape), but somehow, for some reason still had a strobotac, they had to pull the guards on a several thousand HP turbine, and I no poo poo had to stop a dude from doing exactly that.
|
|
#
?
Mar 1, 2021 19:25
|
|
|
FatCow posted:This is amazing. If the latency was low enough this would be unbelievable to weld with, using the output as your vision. When I started watching the video I thought that's what it was and I was so excited  . That would revolutionize welding, a practice that's more akin to art and takes years of experience to get adequate results (TIG welding specifically) precisely because you can't really see what you're doing and have to just learn the feel and timing by repetition. If you could constantly see how far off the piece your tip was, and see how much weld you're putting in? Wow. Of course then you'd get the purist faction insisting that that's cheating and not "real" welding, which would be a shorthand for saying "I slaved away for 30 years learning it the hard way and you should too".
|
|
#
?
Mar 1, 2021 19:43
|
|
|
There is over 100vac between two laptops on different outlets in my house. This is safe, right? Turns out none of the outlets are grounded; there's an miltiwire branch circuit in the basement and some of the outlets have 120v between the neutrals... I'm lucky I haven't let the smoke out of anything or killed myself with this poo poo...
|
|
#
?
Mar 1, 2021 20:28
|
|
|
If they are on different circuits, that is totally normal. The power company sends ~240v to your house split between two phases. Every other breaker in your breaker panel is on the same phase and gets 120v. Double wide breakers are on both phases and can get the full 240v.
|
|
#
?
Mar 1, 2021 20:35
|
|
|
Cojawfee posted:If they are on different circuits, that is totally normal. The power company sends ~240v to your house split between two phases. Every other breaker in your breaker panel is on the same phase and gets 120v. Double wide breakers are on both phases and can get the full 240v. It's a miltiwire branch circuit, so yes I get that. However you shouldn't have 120v between TWO NEUTRAL CONNECTIONS. You will see 240v between two hots on different legs, THAT is normal.
|
|
#
?
Mar 1, 2021 20:37
|
|
|
chrisgt posted:There is over 100vac between two laptops on different outlets in my house. This is safe, right? How did you notice that you have a hot neutral?
|
|
#
?
Mar 1, 2021 20:40
|
|
|
chrisgt posted:It's a miltiwire branch circuit, so yes I get that. However you shouldn't have 120v between TWO NEUTRAL CONNECTIONS. Oh yeah, that's a classic open on a shared neutral, turns the whole shebang into a series/parallel circuit between the two 240V legs, dropping voltage across each one according to the load. The only reason those laptops aren't smoked is the magic of switch mode power supplies. Probably got a couple "ghetto grounds" in there too, (grounding pin bonded to the grounded ["neutral"] conductor) that would explain the hot cases. You got that fixed, right? E: you need to fix that right now.
|
|
#
?
Mar 1, 2021 20:55
|
|
|
chrisgt posted:There is over 100vac between two laptops on different outlets in my house. This is safe, right? Wait, wait, 120v, is that grounded on your USB plug??? Your laptop should only see ~19vDC, how the hell are you getting 105v??
|
|
#
?
Mar 1, 2021 21:09
|
|
|
How could you give your own brother the spicy neutral, Dominic?
|
|
#
?
Mar 1, 2021 21:16
|
|
|
CommieGIR posted:Wait, wait, 120v, is that grounded on your USB plug??? The ground connects through the power supply to the case ground on the laptop. Instead of a proper ground, the ground pin on the outlet that laptop's connected to has been tied to the neutral conductor, probably to fool a home in inspector's "outlet tester" The neutral conductor is broken/has a bad connection somewhere, and because it's a multiwire circuit, has become an intermediate bridge in a series circuit between the two 240V legs, and is therefore at some potential other than 0V to ground as it should be.
|
|
#
?
Mar 1, 2021 21:20
|
|
|
I've heard of etherkillers before but this is ridiculous
|
|
#
?
Mar 1, 2021 21:29
|
|
|
chrisgt posted:There is over 100vac between two laptops on different outlets in my house. This is safe, right? oh noooooooooooo
|
|
#
?
Mar 1, 2021 21:38
|
|
|
https://twitter.com/njdotcom/status/1366492779380170752
|
|
#
?
Mar 1, 2021 22:06
|
|
|
https://twitter.com/PoliceDrones/status/1366083143195897859?s=20
|
|
#
?
Mar 1, 2021 22:22
|
|
|
that's pretty dang cool. did they say how big the bomb was?
|
|
#
?
Mar 1, 2021 22:32
|
|
|
Sagebrush posted:that's pretty dang cool. did they say how big the bomb was? Did a little digging, it's thought to be a SC1000 bomb. 
Rebel Blob fucked around with this message at 22:40 on Mar 1, 2021 |
|
#
?
Mar 1, 2021 22:35
|
|
|
The idea of making a bomb and it ends up sitting dormant for decades before finally exploding is nuts to me. Makes me wonder what the longest time between creation and explosion is. I know there was that guy a few years ago who would restore civil war cannon balls or something, and I think he or someone found some naval bomb and it exploded and killed him.
|
|
#
?
Mar 1, 2021 22:36
|
|
|
Apropros of nearly nothing, if you're ever at the Baltic coast and you find amber: make sure it's actually amber because it may actually be phosphorous that was dumped after WW2. It may auto-ignite in your pocket.
|
|
#
?
Mar 1, 2021 22:46
|
|
|
https://i.imgur.com/o1IhRi1.mp4 Let’s build a giant massive slide that dumps you onto a bunch of rocks in the woods.
|
|
#
?
Mar 1, 2021 23:14
|
|
|
Humphreys posted:Tims Back! Thank you for this, as I'd probably not have heard otherwise. The Secret Life of Machines is a great series, with some very OSHA-looking stuff in it. The bit with them using a welder to heat a pencil up enough for the carbon to glow white hot makes me cringe every time. e: the bit that kicks in around here, but I recommend watching the whole thing as well as every other episode: https://www.youtube.com/watch?v=nvE-m2ueOzI&t=195s Gromit fucked around with this message at 06:00 on Mar 2, 2021 |
|
#
?
Mar 1, 2021 23:22
|
|
|
https://i.imgur.com/mLszwQG.mp4
|
|
#
?
Mar 1, 2021 23:27
|
|
|
SyNack Sassimov posted:When I started watching the video I thought that's what it was and I was so excited
|
|
#
?
Mar 1, 2021 23:29
|
|
|
That vine kid was ahead of his time https://www.youtube.com/watch?v=tyubEwigfUY
|
|
#
?
Mar 2, 2021 00:02
|
|
|
Me, crossfaded as gently caress, trying to get my shoe back on
|
|
#
?
Mar 2, 2021 00:06
|
|
|
https://va.media.tumblr.com/tumblr_qp9xonYQZr1r0uzl6.mp4
|
|
#
?
Mar 2, 2021 00:14
|
|
|
Always nice to see older cats helping out the young ones.
|
|
#
?
Mar 2, 2021 00:25
|
|
|
Kith posted:some people get excited about work My cats do the same little prance when it's dinnertime or they're really happy to see me
|
|
#
?
Mar 2, 2021 00:31
|
|
|
https://images-ext-2.discordapp.net/external/ZjG75Qrdg50BCCEx4_ImPOMd2GG05hppj4cQ_SBgroY/https/i.imgur.com/anBBPSC.mp4
|
|
#
?
Mar 2, 2021 00:35
|
|
|
^^^ As someone formerly severely allergic to tiger mosquito anticoagulant, this is so, so cathartic.^^^ Oooh that sucks. Judged the gap correctly, but failed to notice the deck height change.
|
|
#
?
Mar 2, 2021 00:45
|
|
|
quote:Let’s build a giant massive slide that dumps you onto a bunch of rocks in the woods. 
|
|
#
?
Mar 2, 2021 00:49
|
|
|
Humphreys posted:Tims Back! omg I'm so excited. I love The Secret Life of Machines--it's one of those things from my childhood that was just as wonderful when I went back to it as an adult
|
|
#
?
Mar 2, 2021 00:53
|
|
|
Cojawfee posted:The idea of making a bomb and it ends up sitting dormant for decades before finally exploding is nuts to me. Makes me wonder what the longest time between creation and explosion is. I know there was that guy a few years ago who would restore civil war cannon balls or something, and I think he or someone found some naval bomb and it exploded and killed him. Yeah, that was a guy in Virginia who was killed by a 9", 75 lb cannonball that he was removing rust from. https://www.foxnews.com/story/virginia-man-killed-in-civil-war-cannonball-blast
|
|
#
?
Mar 2, 2021 01:07
|
|
|
Elviscat posted:Oh yeah, that's a classic open on a shared neutral, turns the whole shebang into a series/parallel circuit between the two 240V legs, dropping voltage across each one according to the load. The only reason those laptops aren't smoked is the magic of switch mode power supplies. It's not my house, I just rent. I pulled the offending outlet and put the correct wire to neutral and hot. Now I have 0v between neutrals and 240v between hots. There is nothing at all hooked up to the ground pin, not even a jumper. Although I think it's technically to code to convert two-wire installations by putting a GFCI with a jumper between neutral and ground. There IS a ground wire, but someone cut it off flush with the box, so I'd have to pull the box out, see if there's any loose wire in the wall (there isn't) and then splice in a new piece. Why they did this is beyond me. None of the outlets in the entire house are grounded. Not a single one. Not even the GFCIs in the kitchen and bathrooms....
|
|
#
?
Mar 2, 2021 01:25
|
|
|
|
| # ? Jun 6, 2024 01:55 |
|
|
Someone took major shortcuts with the electrical work to make it look like it has grounds without actually doing any work or spending any money. Now ask yourself what shortcuts they took in places that aren't as easy to spot - is all the wiring in the walls sized appropriately for the breaker they've installed? How do you know?
|
|
#
?
Mar 2, 2021 01:34
|
|
