sparks and wedding rings

[Kurt]

Today once again I felt a hot spark on my finger as my wedding ring tyred to weld its self to the side of 60v worth of battery.I think this would be the 3rd time this has happened over the last year or so. I am getting better at polishing out little craters from my my titanium wedding ring before my wife discovers them

Just wondering how many other people have been as silly as me and what kind of welding you have done with you battery ?

kurt

 

[fechter]

I've been lucky with the ring so far, but I did weld a stainless steel watch band once. Several wrenches and wire strippers have been fried too. One should be very careful.

How about some clear heat shrink over the ring?

 

[pwbset]

Not married yet, but did have to get a new multimeter because my leads eventually vaporized to a point they didn't read very well anymore. :lol:

 

[Kurt]

Every multimeter i have owned I seem to make the mistake of measuring amp draw and then without thinking trying to measure voltage without changing the Leeds around. They don't like having a dead short through them.

 

[Zoot Katz]

Working with power tools and heavy materials I learned a that even a simple band can be a hazard or get destroyed in normal activities.
An acquaintance wears his squashed wedding band on a neck chain after it severed his finger when he got his hand caught under an actual tonne of styrofoam.
There are some jobs where steel watch bands are specifically proscribed.
Geeks don't want anything metallic dropping out of their pocket protectors either.

 

[Link]

I don't wear any watches, rings, or necklaces for this reason.

And I imagine a ton of styrofoam must be an impressive sight. But how do you manage to actually crush something under it, seeing as how it's pretty soft?

 

[Zoot Katz]

I don't wear any watches, rings, or necklaces for this reason.

And I imagine a ton of styrofoam must be an impressive sight. But how do you manage to actually crush something under it, seeing as how it's pretty soft?

A tonne is a tonne. Dropped from a height it's considerably more.
Styrofoam only posed part of the equation. Undoubtedly it was wrapped. The hard surface under his hand would be another factor.

I'd not care to attempt an experiment proving what he told me.

 

[Kurt]

When it comes to electric work I think rings can be a problem but my ring has saved my finger once. Being a fitter and machinist in a maintenance role while testing some adjustments I made to a rotary filling machine I had a air cylinder actuate onto my hand but didn't chop my fingers off because my ring stalled the cylinder.

 

[dogman dan]

The exception that proves the rule. Like the guys that say steel toes cause amputations. After 30 years in construction I can still count to ten on my fingers, and won't wear a ring, or watch on the wrist.

 

[Link]

Like the guys that say steel toes cause amputations.

I find that one kind of interesing, since if something heavy enough to even bend a steel-toed boot lands on your foot, it's not like you would have been any better off without it.

And MythBusters tested that one. Their findings agreed with me. :wink:

 

[TylerDurden]

Steel-toes are better than sneakers when hot metal from welding drips.

I gave up the idea of any jewelry or watches after I beat the crap out of anything I wore: Work, sports, electronics, auto repair, lightning strikes... fuggit, I look pretty enough and I can see the clock.

 

[Ypedal]

I only once.. got careless and introduced my anderson crimp tool to the discharge leads from an 8ah 36v nimh pack, i almost launched those suckers right thu my 32" Sony Vega TV !! ( it's got a nasty chunk missing on the wire cutter side )

The dog went from deep sleep on the couch, to the other side of the kitchen faster than the speed of sound !!!

All i wanted to do was make sure both wires were gonna be the same lenght !!. . doh..

 

[swbluto]

Lucky me, I don't really wear any ... accessories.

 

[MidniteTweeker]

Guy I know was using a wrench to tighten the hot side battery clamp on the 24 V system on his semi truck. Swung the wrench and bumped the chassis. Good news was, he had his hand cupped over the end of the wrench so the wrench didn't strike bare metal. Bad news was, his gold ring completed the circuit between wrench and chassis. Result: One destroyed ring and 360 degrees of 3rd degree burn around his finger that took a long time to heal.

This was also the guy who put his finger over the end of the pressure washer nozzle to make it spray harder. That took a long time to heal, too.

MT

 

[deecanio]

mmmmmmmmmm.
Any kind of jewelry can be dangerous when working on the bikes/machinery.
I used to work on vending machines many moons ago and i never understood why the company insisted on us wearing ties wtf you want me to wear a tie whilst working on coffee grinder gears ?
Anyway im married now but ALWAYS take my wedding ring off if working on the bike, just easy to slip it off and put it back on when your done.

Cheers,

D

 

[dogman dan]

I've done the wrench touching the fender thing several times on cars. Stopped being casual about that stuff the first time I bumped the leads together on the 36v sla pack. NEW RESPECT for battery wires! My 48v sla pack may be a better welder than my cheap chinese stick welder. All the construction workers I ever heard argue steel toes would cut your toes off were also unable to read a blueprint. :lol:

 

[ngocthach1130]

All i wanted to do was make sure both wires were gonna be the same lenght !!. . doh..

Lol i did the same before too. wires on my 48v SLA battery pack was uneven. Sheer stupidity lead to to think cutting both wires at the same time with wires cutter will save time. Made myself a pretty huge guage wires stripper in the process hehehe.

Another time i was opening up dewalt pack to tap the leads inside. had wires crimped and as i was pulling them through the holes i made i inadvertently left the contacts exposed without the housing. Needless to say those dewalt pack can crank some amps. Reduced both contacts to smoldering ball of copper on my carpet.

Okay, one more stupidity story. As i was solding wires to my 48v SLA packs i found it is easier to tie the battery tab and wires together first to hold them together using tiny copper wires. Then all i had to do was heat the tab and add solder, no need for a third hand to hold the wires in place. So here i go holding this tiny filament in my hand and wounding the tab and wires to one tab when the end of the wires touched the other poles and complete the circuit. It's like holding ovens heating element in your palm. Went glowing and wires start carving into my palm and up toward my index finger.

 

[recumpence]

I haven't had any issues myself, but, about 7 years back I was into competition SPL (car audio). A local shop had a tech that got his wedding ring stuck between the buss bars on the caps (4 one farad caps) and (I think) 4 batteries. The wedding ring got red hot instantly and pretty much vaporized the skin on his finger as he pulled it out of the ring.

Lots of power in those caps and batteries.

Another lovely sight was the idiot who lost his hair and the better part of his scap when it got caught in a milling machine. Gee I wonder why they have a "Short hair only" policy now.

At any rate, I do appliance repair. I work on appliances "Hot" all the time. I have never taken electricity for granted.

Matt

 

[dogman dan]

Holy crap! sparks flew just an hour ago, checking the voltage on my Ping after a charger tweak. The plug has a female pole and a male pole so you can't plug it backwards and one slip of the probe on the male one, and I'm welding again. Sheesh Kinda suprised the multimeter still works.

 

[Link]

Lol i did the same before too. wires on my 48v SLA battery pack was uneven. Sheer stupidity lead to to think cutting both wires at the same time with wires cutter will save time. Made myself a pretty huge guage wires stripper in the process hehehe.

LOL, okay, who here has NOT done this? I did the same thing with a pack of the same chemistry and voltage. Luckily for me, it was only a 4.5Ah pack and unable to deliver much current. Still blew a hole in my wire strippers, though.

And WOW, would I not like to get anything stuck between a cap/battery combination.

 

[swbluto]

Lol i did the same before too. wires on my 48v SLA battery pack was uneven. Sheer stupidity lead to to think cutting both wires at the same time with wires cutter will save time. Made myself a pretty huge guage wires stripper in the process hehehe.

LOL, okay, who here has NOT done this?

Uhhhhh... it's me again. :lol:

But I've made sparks fly when forgetting to remove the "series" wire when paralleling my old Lead Acids for parallel charging. So I'm not completely immune to short circuiting. Luckily, though, it was easy to quickly react in a safe manner.

Sometimes I like flicking leads together to watch sparks fly. I'm thinking that something based on this concept could be used for a portable battery operated fire-starter.

 

[Link]

Sometimes I like flicking leads together to watch sparks fly. I'm thinking that something based on this concept could be used for a portable battery operated fire-starter.

I did that in front of my little cousin once. She was bugging me when I was working on one of my skateboards. So, I start going on a little about some of the stuff that can happen when powerful circuits get short circuited (spark, fire, mini-explosion in really power-laden circuits [e.g. 480V mains]) and accidentally touch the main leads together. Kept her out of my hair when I was working on that stuff ever since. 8)

As for a fire starter, I'm thinking the piezo igniters have the edge. Small and light. Not pleasant to have one go off on your hand, though. :? Mebbe something like a glow-plug if you were going to use a battery...

 

[recumpence]

A month back, I was plugging my battery pack into my controller on my bike (I have two connectors in parrallel to take the load better). I plugged one in just fine. The bank of caps on my controller snapped as they charged (as usual). Then, the second connector swung over and the positive terminal touched the negative--- BANG! It blew 1/4 of the connector spade off as the caps discharged backward against the current coming out of my lipo. WOW, that was a huge spark!

Matt

 

[Kurt]

Well I did it again, this time there was no jeweller involved. I stared out by pulling the aluminium covers off of my 48v speed controller with plans to tap into the throttle signal so my cycle analyst can do some current limiting.

With some help from Justin at ebikes ca all was going well. I had my little diode hooked temporarily to the low current side of my throttle input on the speed controller .By temporarily I mean the legs of the diode were just hooked under the resistor on the speed controller board.

I ran a small test by dialling in a 1amp limit into the CA . Everything worked perfect and the output was limited to 50w. All I had to do was just tidy everything up and solder it in permanent and I was set .

The next thing I know there is a big crack and a plasma like flame coming from the top of my controller. before I could get over to the bike all 6 fets had exploded and literally jumped off the controller and onto the floor as a glowing red ball of steel. What was remaining of the controller was on fire. I killed the main power and snuffed out the fire

I think the naked controller board shorted on the bike frame or the diode leg dangled onto something and stared a snowballing shorting episode. The interesting thing was looking at the data on the Cycle analyst.
Max Amps 187
Min volts 42v.
I am using 4 x 20 ah sla jump starter packs at least I know they are ok for C10 discharge in short bursts I also know that my chines e crazyman speed controller cant handle 8000w

I took my wife's speed controller of her bike so I am back on the road now .I haven't told her that yet .