- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
Usually, when I skip it, it's because I don't want to spend an hour tracking one down. I always have a roll of tape on my bags to use that works just as well. 
mc connectors
- Thread starter 19clapshaw82
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georgestolz said:Usually, when I skip it, it's because I don't want to spend an hour tracking one down. I always have a roll of tape on my bags to use that works just as well.
How do you get the tape between the jacket and the conductor ?
That's the only way it would work just as well.
electricalperson
Senior Member
- Location
- massachusetts
i have a pretty large supply of redheads in my van
wirebender
Senior Member
- Location
- North Central Texas
Me, too. That's one of those items that you can't use them all.
wirebender
Senior Member
- Location
- North Central Texas
dnem said:
You just pull the jacket back a little before you tape.
- Location
- Massachusetts
dnem said:
Push the armor back while pulling on the conductor, it actually works pretty darn well, better then a anti-short. But I would rather use a red as it's faster.:smile:
peter d
Senior Member
- Location
- New England
iwire said:
I think that method works best on the larger sizes of MC cable.
wirebender said:
Years and years ago during my high school / vocational school electrical program years, we put Scotch 33 thru a test. . One wrap of tape across a buss bar and we touched a grounded 12gauge against the tape [the teacher was unaware of our experiments including our electrocannon experiments]. . The tape insulated the 277v buss. . Thumbs up for the 33 ! :smile:
So being the enterprising and highly intelligent [or maybe it's highly enterprising and slightly intelligent]
young lads that we were, we decided apply some pressure on the 12gauge. . The dented single wrap of 33 held firm. About that time one of the guys finally allowed some common sense to peek thru. . He suggested that the guy holding the 12gauge should put on some gloves and safety glasses. . So we figured that was OK, not too wimpy.
Some next up was too press the 12gauge into the tape and then twist it back and forth. . That resulted in roaring explosive flash and a shower of sparks. . The lights also went out and because we were somewhat blinded by the flash, noone knew who might be burnt or on fire. :-? . But there seemed to be only pitch black [no windows in the lab room] and no flame apparent thru the blackness and nobody screaming in agony. . Since nobody was making a noise my next thought was, "Could it be that they're all dead ?" . But then someone coughed.
It turned out that everybody escaped without a single injury [other than retina flash], even the guy that was holding the 12gauge.
. It also turned out that we took down the power to that whole wing of the building [no selective coordination/series combination rating in that building]. :wink:
wirebender
Senior Member
- Location
- North Central Texas
Well, that settles it.
If I ever wire a building where you and your high school cronies are likely to have access I will use rigid conduit and explosion proof boxes with locking covers.
If I ever wire a building where you and your high school cronies are likely to have access I will use rigid conduit and explosion proof boxes with locking covers.
brian john
Senior Member
- Location
- Leesburg, VA
Do we need a poll Red Eyes with MC Yes? No?
sandsnow
Senior Member
- Location
- Southern California
dnem said:
It was great to be a kid, wasn't it.
When I saw 12gauge I thought "What is he doing with a shotgun shell?!?!?"Tell us about the electrocannon experiment
brian john
Senior Member
- Location
- Leesburg, VA
My favorite trick was laying a piece of 4/0 across a 12 VDC battery and watch the insulation melt. Bolt one connector the the positive or negative post the hit the other post with the other end of the cable.
electricalperson
Senior Member
- Location
- massachusetts
dnem said:Years and years ago during my high school / vocational school electrical program years, we put Scotch 33 thru a test. . One wrap of tape across a buss bar and we touched a grounded 12gauge against the tape [the teacher was unaware of our experiments including our electrocannon experiments]. . The tape insulated the 277v buss. . Thumbs up for the 33 ! :smile:
So being the enterprising and highly intelligent [or maybe it's highly enterprising and slightly intelligent]
About that time one of the guys finally allowed some common sense to peek thru. . He suggested that the guy holding the 12gauge should put on some gloves and safety glasses. . So we figured that was OK, not too wimpy.
Some next up was too press the 12gauge into the tape and then twist it back and forth. . That resulted in roaring explosive flash and a shower of sparks. . The lights also went out and because we were somewhat blinded by the flash, noone knew who might be burnt or on fire. :-? . But there seemed to be only pitch black [no windows in the lab room] and no flame apparent thru the blackness and nobody screaming in agony. . Since nobody was making a noise my next thought was, "Could it be that they're all dead ?" . But then someone coughed.
It turned out that everybody escaped without a single injury [other than retina flash], even the guy that was holding the 12gauge.
thats a pretty scary story right there
sandsnow said:
I hate to totally abandon the topic of the original post but the electrocannon was awesome.
If you make a fist with one hand and then cover it with your other hand, that was about the size of each coil in the electrocannon. . It had 2 coils slipped over a 1/2" PVC muzzle strapped with minis. . It had the coils about 4" to 6" apart and anchored to a wood 2x something or another. . It was connected to an AC power supply but had a diode in series with each coil. . The 2 diodes were installed opposite polarity/direction for each coil so that only one coil would see current at a time and only for half a sine wave cycle. . They flipped one coil 180? before they slide it onto the PVC because they weren't sure if the positive half cycle would launch a projectile thru the first coil but then the negative half cycle would put the breaks on it thru the second coil. . They asked us smarter kids if they should flip that second coil and we discussed it among ourselves and came up with the brillant answer:
"We don't know."
Anyway, the above paragraph was the stated concept but there was tinkering and experimenting involved and I'm not sure of the final settled idea. . I know that it was built by the more gutsy guys and not by the smarter guys. . So who knows what they actually did. . They weren't very cooperative about answering specific technic questions about how they did what they did and why ..... especially since they weren't happy with our answer to the only question they had asked us.
The cannon was connected to a lab unit that had a dial for varying frequency and they did test launches of ball bearings while varying the sine wave frequency. . Or at least they thought they were varying the frequency, who knows, they were turning dials and saying that they were varying the frequency. . I believe they said that they concluded that 5 to 10 hertz launched the most thrust for a given voltage.
The cannon was set slightly off level so that you could pop a ball bearing into the slightly lower end and just hold your hand over the hole to keep it from rolling back out before launch.
We then started to blast the bearings into wood studs at greater and greater voltages. . At lower voltage the bearing would actually bounce off the wood and come back thru the lab. . But we were confident that at higher voltages we could get it to penetrate the wood and "stick the landing".
Us smarter kids felt we had to speak up with confidence about penetrating the wood because we were trying to make up for our previous answer [that they referred to as our "blank" answer but they didn't say "blank", they used a word that sometimes means a cat and ends with a Y, if you know what I mean].
But we did take the greatest of precautions ..... we put on safety goggles, not just glasses, but full googles, and not just the guy launching but everybody in the lab. . We were at the very forefront of safety for our time ! . Safety was tip top priority so the non"shooters" would stand in front of the glass windows at the front of the lab to block any stray bearing from hitting the glass. . Safety goggles on, one hand over your teeth, the other hand over your nuts, and wait for somebody to say, "Houston we have lift off !"
As it turned out, everyone of the higher voltage launches "stuck the landing" and no bearings ricocheted into the human shield.
End of story, right ?
Nope !!!
Somebody got the idea that we should take the cannon to the school roof and see if we could send a bearing into the nearby woods which was about 1000' from the school. . We already had a route to the roof, thru the ventilation ducts. . Unknown to most of us in the class, a few of the guys had already unscrewed a return air duct vent and had been crawling up thru the return air ducts in search of the grate over the girls restroom [but there were rows of little fins at some of the duct bends so the restroom attempt was not successful].
So we unspooled a 250' of 14/2 and ran it up the duct work to a spot were we could get it out onto the roof. . Because we had a legitimate [instructor assigned] electrical project on the roof, we had no problem stationing men up there [the legit project was something about the TV antena but it was so boring that I can't even remember what it was]. . We debated how to get the electro-cannon up onto the roof and decided to just carry it up, right out in the open. . We were carrying other stuff for "cover", like benders that we didn't need, and nobody gave us a second look.
We had walky talkys at both ends so we could have a lab man vary the voltage. . We found out quickly that the biggest problem was that noone could track the ball bearing and we had no idea how far we were actually shooting. . We couldn't hear any feedback and it wasn't that long before the roof guys/shooters were starting to get bored ..... sooo ..... somebody came up with the idea of targeting an outbuilding on the edge of the parking lot. . The first launch was the issue because we couldn't figure out how to determine for sure if the bearing would clear the parking lot. . There was also so talk about ricocheting and the teachers area cars that were just next to the building. . A few guys were "absolutely sure" that we would clear the parking lot and brushed away the talk of "bounceback"/ricochet. . Strange thing was that those guys didn't want to "man" the cannon personally.
Some names were thrown around such as "little girl" and "mommas boy" and others that I can't write here, but when one guy volunteered to launch in the direction of the parking lot, but said that he was going to point it at one of the other guys car, then it got a little nasty. . Finally somebody asked, "If someone is sleeping in a car in the parking lot and we hit 'em, do you think we would kill 'em ?" . There was silence for a number of seconds.
One of the guys pointed out that we hadn't seen any movement in the whole parking lot for "a good 15 minutes" and there "probably wasn't anybody still in the parking lot anywhere". . Another of the guys spoke right up, "Probably !? . What do you mean probably ? . There's nobody out there anywhere." . But he seemed to trail off in that last sentence and I don't think even he himself was even half as sure as his tough guy words were intended to be. . I kept my mouth shut. . Inside I was thinking, I hope they drop this outbuilding idea because I don't want to have to be the one who speaks up against it and be the "mommas boy".
After that short exchange between them, the atmosphere was like somebody let the air out of a balloon.
Some of the guys started pretending to fiddle with some of the stuff on the roof. . As if the official school project that we had going up on the roof was suddenly important. . Nobody wanted to actually say that we were backing down from the outbuilding idea. . Eventually somebody said something about it being a few minutes before the end of lab and we took the cannon back to the classroom.
We shot it in the lab a few more times on various different days but eventually it was dismantled it.
There were other ideas to play with. . We thought that cannon was the coolest thing on Earth at one time, it's kind of strange that it just didn't hold our interest after a while.
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JohnJ0906
Senior Member
- Location
- Baltimore, MD
David, how old were you when you did this stuff?
JohnJ0906
Senior Member
- Location
- Baltimore, MD
dnem said:
Gotcha. :wink:
Actually, you guys were a little on the mellow side...
brantmacga
Señor Member
- Location
- Georgia
- Occupation
- Former Child
dnem said:
Isn't this what's known as a gauss gun?
I have an electrician friend that used to build those. Last time we talked about it, he was working on building a rail gun; which is completely awesome.
electricalperson
Senior Member
- Location
- massachusetts
in the video game "planetside" the rifle was called a gauss ors omething like that. it fired using magnetic waves to propel the bulletsbrantmacga said:
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