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  #1  
Old 08-31-2002, 02:58 AM
xash xash is offline
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does superglue conduct electricity or how do i glue two electrical contacts ?

i need to glue two electrical contacts together... what is a recommended glue to use ?

the original glue has worn off, and the two parts have come unstuck... i was wondering whether i could use superglue or whether i needed some specific conducting glue ?

i thought about soldering, but i'd rather use glue...
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  #2  
Old 08-31-2002, 04:24 AM
sailor sailor is offline
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I do not think any glue will work, at least not as well as soldering. I recommend soldering. It takes a few seconds and it's done.
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  #3  
Old 08-31-2002, 06:14 AM
Squink Squink is offline
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What are the contacts made of ?
Is it a 5 volt circuit, or 110 volt ?
You say the original glue has worn off. Was it actually on the contacts, or just on the housing around the contacts ?
If it's a low voltage circuit, the contacts are probably springy metal, in a plastic housing; and the glue simply holds the two bits of plastic together.
If that's the case, you can use any good plastic glue. Just be sure not to get any on the contacts themselves.
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  #4  
Old 08-31-2002, 08:51 AM
Bryan Ekers Bryan Ekers is offline
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In my shop, we routinely soldered electrical connections together, then covered the connections using a hot-glue gun. The glue itself is not conductive, but its presence was to protect the contact (and the people who might touch the contact), not to ensure a good electrical connection.

Solder first, glue afterward. Hot glue is better than superglue because (when cool) it isn't sticky any more, taking the form of a hard plastic shell.
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  #5  
Old 08-31-2002, 09:29 AM
matt matt is offline
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Superglue doesn't conduct. If you want to "glue" an electrical contact, there are conductive paints used to bond electron microscope specimens onto mounting stubs but they are expensive and difficult to get hold of, and have little mechanical strength. I have used them, and covered the joint with epoxy for strength after the paint has dried, but soldering is easier, faster and more likely to work.
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  #6  
Old 08-31-2002, 10:00 AM
Spit Spit is offline
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Super-Glue will not work, as I speak from experience.

Christmas, 1991:

My youngest step-brother got a pair of cheap walkie-talkies. I decied they didn't transmit far enough, so my other step-bro (who was my age) and I decided to take one apart, and replace the 'duck' antenna with a whip.

An hour into the project, we realized that we screwed up, and started to put the mess back together...Only to find that the wire from the positive section of the antenna had to be soldered on to the circuit board.

Hmmmmm...No soldering iron handy, and dad would be pissed if he knew we tore apart the talkies. Superglue to the rescue!

It didn't work.

On a lighter note, after my younger step-bro quit crying, my dad patted us on the back for being so interested in radio. (hey, we were all hams) However, we had to buy him new walkie-talkies.

So the bottom line: No, Super-Glue will not work.
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  #7  
Old 08-31-2002, 10:19 AM
DougC DougC is offline
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- - - There are repair kits for car window defrosters that may. The kits contain some type of paint/whatever (?) that you use to re-paint breaks in the little metal defroster lines on the rear window. (I need to fix the back window o' me ride, never got around to it yet,,,). When I searched the net, there only seemed to be a couple of companies that made them.
~
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  #8  
Old 08-31-2002, 10:32 AM
Bryan Ekers Bryan Ekers is offline
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Quote:
Originally posted by DougC
- - - There are repair kits for car window defrosters that may. The kits contain some type of paint/whatever (?) that you use to re-paint breaks in the little metal defroster lines on the rear window. (I need to fix the back window o' me ride, never got around to it yet,,,). When I searched the net, there only seemed to be a couple of companies that made them.
~
I have the same problem. The defroster connector broke and I had a heck of a time working with that liquid solder. I eventually took it to a garage and watched the mechanic do it. Now the damn thing's broken off again and I have to take care of it before winter, but at least I have a better idea how to go about it.
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  #9  
Old 08-31-2002, 11:07 AM
DougC DougC is offline
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http://www.frostfighter.com/ff_resourcs.htm
~
This is the "big" company, I found a smaller one somewhere also.
I haven't tried the stuff yet.
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  #10  
Old 08-31-2002, 11:17 AM
DougC DougC is offline
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- - -We Shall See Soon Enough: I just ordered the $20 defroster repair kit from Frostfighter.
~
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  #11  
Old 08-31-2002, 03:21 PM
Mangetout Mangetout is online now
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I've seen conducting glue in the RS components catalogue; it was a long time ago, but they may still sell it - it was an epoxy resin glue (two tubes) loaded with silver flakes.
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  #12  
Old 08-31-2002, 04:10 PM
Crafter_Man Crafter_Man is online now
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For crying-out-loud, solder the damn thing and be done with it...
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  #13  
Old 09-01-2002, 05:14 PM
xash xash is offline
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thanks for your responses. so, superglue is a non-conductor then...

ok, here's what i'm trying to do:

it's a part on a handspring visor prism. the pins at the back and bottom of the visor, which connect the visor to the synchronizing cradle, have come loose. basically it's a plastic block with pins residing in it... i can't explain it too well, but let's just say that it has two metal jutting outs that were connected to two metal points on the board of the handspring... when these were glued tight together, as originally, each pin in the block automatically sat on top of it's corresponding contact point on the board... but with this glue having come unstuck, the plastic block keeps getting misaligned... to fix it i need to glue these jutting out two metal parts to their two metal contact points on the board...

the thing is i don't have a multimeter, so i can't check just yet whether these two metal parts that jut out of the plastic block actually form part of the circuit or whether they're there just to keep the rest of the pins aligned properly...

it seems to me from the pcb that these two metal parts are part of the circuit, but i'm not sure, and can't confirm it yet...

also, i don't have any solder wax... i just have solder wire and a soldering iron... i was wondering whether that might lead to a dry solder ? i haven't soldered anything in a long time, hence i was more keen on using a conductive glue...
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  #14  
Old 09-01-2002, 08:07 PM
Crafter_Man Crafter_Man is online now
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Quote:
Originally posted by xash
also, i don't have any solder wax... i just have solder wire and a soldering iron... i was wondering whether that might lead to a dry solder ? i haven't soldered anything in a long time, hence i was more keen on using a conductive glue...
Wax? I assume you mean flux. I rarely use flux when soldering electronic components, since the surfaces are usually tinned or appropriately plated. Besides, most solder used for electronics ("rosin core") contains flux in the core.

I'm still a little confused what this thing looks like. At any rate, you need to find a way to create a good, reliable connection. If there's a way it can be soldered, then solder it.
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  #15  
Old 09-01-2002, 09:42 PM
DougC DougC is offline
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- - - A couple months back when I first started looking around to fix my window defroster, I went to Radio Shack and asked if they had anything that would work, and they couldn't find anything. They coulda been just maroons, but I find nothing in the online catalog.
~
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  #16  
Old 09-01-2002, 10:35 PM
Musicat Musicat is offline
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Clean off any old "glue" with solvent. Solder it with a modest amount of 60/40 rosin-core solder. This will assure a good electrical connection.

What you assume is glue is probably "dope", or an electrical non-conductor plastic-like substance that is brushed or sprayed on after solder is cool. Dope adds slightly to the physical joint strength and protects against shorts with nearby objects. It often comes in different colors, which are sometimes used as a color code for various reasons. It's doubtful if your circuit really needs it to operate, but the electric connection is critical.
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  #17  
Old 09-02-2002, 01:46 AM
xash xash is offline
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Quote:
Originally posted by Crafter_Man


Wax? I assume you mean flux. I rarely use flux when soldering electronic components, since the surfaces are usually tinned or appropriately plated. Besides, most solder used for electronics ("rosin core") contains flux in the core.

I'm still a little confused what this thing looks like. At any rate, you need to find a way to create a good, reliable connection. If there's a way it can be soldered, then solder it.
yes, i meant flux

ok, try this for what it looks like:

<--------->

consider a block like above (assume it to be a chip, which it's not) ... and let's say the dashes are the pins, which are definitely part of the circuit... and the two arrows are the metal parts that i want to solder/glue. these two arrows attach to metal contact points on the pcb, and when that happens, each pin contacts with its own contact point on the pcb. once i figure out whether the two arrows are part of the circuit, then i'll probably solder it. if it's not part of the circuit and it's there only for alignment purposes, then i'll just superglue the thing.
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  #18  
Old 09-22-2002, 06:27 AM
DougC DougC is offline
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- - - Update: the defroster-grid repair stuff arrived, but I haven't had the chance to actually try to use it yet.
A couple notes:
- $24 bucks don't get you much of the stuff. The contents of the "repair kit" are two pages of instructions covering all the different repair kits, a short roll of narrow masking tape, a couple cotton swabs and a small bottle, maybe 1 cm x 2.5 cm. The cap is about 1/3 that height, and it has a dip-stick. The bottle itself is only about half-full.
- The contents of the bottle smell exactly like ordinary fingernail polish. The instructions say something about "a highly conductive silver filled polymer repair compound" and warn you against inhaling the fumes. The instructions note that it dries to the touch in 10 minutes and is fully usable in 30 minutes.
- The stuff is colored a dark coppery-brown. Almost as if someone had mixed some powdered copper into clear fingernail polish. I don't have any powdered copper around to try myself, and I don't remember enough of my chemistry to know if that would work or not. Looks about like it though.
~
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  #19  
Old 10-19-2002, 09:54 PM
DougC DougC is offline
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- - - (whap whap whap whap) I used the stuff, but it hasn't been foggy enough to see that it actually worked. I did find that the ingredients are listed inside a wrapper, where I hadn't looked before: Silver (metallic)(7740-22-4), Butyl Acetate (123-86-4), Propylene Glycol Methyl Ether Acetate (118-65-6), Acrylic Resin (non-hazardous), Monoazo Red Pigment (non-hazardous).
- After it dried and I removed the masking tape, the paint was visibly filled with tiny silver flakes. So.... -silver, not copper.
~
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