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Yeah, overloading the tailgate would have been my worry. Not so much that it would collapse, but some part would bend slightl6y and then the gate would never seal right afterwards.
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They also stop instantly and self -destruct if you ansent-mindedly use one to cut ESD conductive foam because someone else was using the band saw.
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Yep. You have to replace a part, and the blade. They demonstrated one for our Fine Arts Department. We bought two of them. Students’ fingers are much safer.
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Naive question: If it stops for a finger, how does it know to not stop for a block of wood?
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From her profile I believe she is based in Sunnyvale CA, where her engineering skills might be useful. Apparently the city is overrun with crows and they are considering lasers, bottle rockets and firecrackers as possible solutions, according to NYT: A California City Is Overrun by Crows. Could a Laser Be the Answer? - The New York Times
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- The blade carries a small electrical signal.
- When skin contacts the blade, the signal changes because the human body is conductive.
Curious about the limits of conductivity…guess you have to consider what you’re about the try cutting? Limited to wood?
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I imagine the exact details are proprietary. Let’s just say I wouldn’t try to cut wood that’s been soaked in brine.
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Quick experiment. Comparing the resistance of dry wood, wet wood, human skin, and summer sausage.
Dry wood (open circuit)
Wet wood (tens of megaOhms)
Dry skin (MegaOhms)
Summer sausage (hundreds of kOhm - MegaOhm)
There is an order of magnitude difference in impedance between wood products and skin or flesh analogs. Fairly easily detectable difference.
Cavaet: wood that is soaked through could have a resistance comparable to human flesh, but why would you cut that on your tablesaw? Relative humidity should be around 3%-8%. Where’s @Wanderfound ?
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We have a collection of come-alongs (single-gear and dual-gear) and their existence has changed the way I deal with moving heavy loads into and out of our old Toyota truckbed. My spine and back muscles are better off as well.
Having some tow-straps and some posts with solid footings, or mature large single-trunk trees is useful. So’s attaching one hook to the loop underneath some cars that is a tie-down used for shipping (the car) long-distance. Even hooking one side of the come-along and tow-strap to another truck with a trailer-hitch is fine.
Love inclined planes.
Humans are tool using animals. And I do love simple machines.
ETA: typos
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That was a satisfyingly methodical and safety conscious procedure to watch, real nice to see a tricky job executed with all due care.
On the other extreme of unbridled chaos, once witnessed a contractor dude rapidly remove a trashy 45lb table saw (stand had been detached), from the surface of second-story porch. He’d been attempting to ill-advisedly rip a small sheet of ply - and when the blade (predictably) binded, it quickly transferred all that rotational energy into the the saw, which dutifully obeyed Newtons Third law - and jumped up through the air somersaulting over the railing onto the lawn below.
In some situations glove are counterintuitively a real hazard - specifically with certain shop equipment having spinning shafts (mills and lathes) and especially any exposed belts. Gloves present more surface friction than bare skin, causing hands to get pulled into the works. It’s not the dexterity reduction that makes it dangerous - but the reduction in sensitivity/reflexive recoil + grabbiness that makes a bad combo, (this is according to some hand-reassembly folks I’ve spoken with, and woodshop people). That said - we should always use appropriate safety gear.
Yep, found that out the hard way when building a 30KV Jacob’s Ladder one time in college using wooden spacers - (even dry wood is a decent (resistive) conductor with enough volts, (and charcoal is even better)). “Hey - where’d my spark go - and what’s that burny smell?” - (…that explains those glass/ceramic standoffs on the power poles).
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My initial thought wasn’t wet wood, but more exotic things like carbon fiber composites, or carbon black filled plastics. Got way more detailed answers than I expected!
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Carbon is quite conductive. The ESD conductive foam I described above is impregnated with carbon and will trigger the stopsaw
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I did wonder why she didn’t take it off first.
There’s a type of accident involving mills and lathes known as “degloving”- don’t google it if you have a weak stomach. I’ve also seen pictures of the aftermath of what happens if you get sucked into a lathe- I don’t have a link to those pictures, and they are equally horrific.
I had an incident last year with my table saw where the push stick I was using came into contact with the blade while the saw was spinning down- while I wasn’t injured, the stick got a nasty gash in it, was ripped out of my hand, and was flung to the far end of the space the saw was set up in. I was Done Work For The Day at that point.
Respect your tools, and use constant vigilance around them.
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Thank you. It gave me a chill when I noticed the sandals too. 
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I’ll bet that’s why she was wearing open-toed shoes: It needs to contact skin to come to a stop, so if it fell off the ramp and onto a shoe it would crush her foot, but having bare toes allows the safety mechanism to activate and instantly halt the vertical movement of the saw before breaking any bones.
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Huh… I did exactly that same thing last summer - and got a smashed finger for it. I’m not sure why that happened… so do you understand what does that? Is it any contact by the push stick (in which case maybe I’ll use some wood next time?)
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