Wiring Without Soldering?

[Otokoyama]

If you have something that's too large to sufficiently heat up to permit soldering, how would you cleanly and permanently attach a wire to it? Is there any electrically conductive (0 resistance) epoxy/adhesive?

 

[Tomas]

For making an electrical connection to a large mass I would do one of the following:

1) Larger soldering iron

2) Torch (used for plumbing and roofs, for example)

3) Drill, tap, and use a screw

4) Sheetmetal screw

5) A compression fitting/connector

6) A screw-type compression fitting (as on large power leads)

7) "Something else" that exerts continuous mechanical pressure so that the two electrically important parts stay in good contact.

Without further information on what is being attempted, that's the best I can do.

 

[Joe400]

From time to time I've had to used "Silver Print Conductive Paint". Its a pure silver paint used for circuitry. Its made by GC Inc. - #22-202 but Im sure their are other companies that make something similar.

 

[tvodrd]

8) Use an Exacto or Dremel slitting saw to make a slot, into which your wire may be staked/crimped.

Larry

 

[Zelandeth]

Not sure, but I'd certainly like to know, I've got some 5mm LEDs where I wish to solder or attatch in some similar manner to a large metal body (Heatisnk in this case) and obviously, more heat isn't an option.

 

[McGizmo]

I have used mostt of the methods mentioned above as well as some electrically conductive epoxy. I noticed on one of the lablels that post curing the epoxy decreased the cure time but more importantly increased the conductivity.

- Don

 

[Otokoyama]

I googled for the "Silver Print Conductive Paint" (thanks Joe400) and found CircuitWorks Conductive Epoxy at Action Electronics (CT-CW2400). In my case, I think this should do the trick.

I had originally used an Exacto saw intending to stake (thanks tvodrd), but messed up the workpiece and didn't want to throw out a few hours of work.

McGizmo, what do you mean by "post curing the epoxy", since I do want maximum conductivity?

 

[McGizmo]

Otokoyama,

Sorry,

Many epoxies can have improved physical properties if they are cured in elevated temperatures after they gel. In the case of the electrically conductive epoxies I have used, both the Circuit Works and MGChemicals, they recommend heating the bond to between 150 and 250F for 10 minutes. I usually cook my stuff at 160 F for 15 minutes or so.

- Don

 

[markus_i]

Depends on your boundary conditions. Basically nothing is too large to permit soldering if you have a sufficiently large oven, but you may be limited if whatever you want to solder can't stand sufficient heat for sufficient time.
In addition to Tom's post, yes, there are conductive adhesives and there are also low temperature solders, but they all have disadvantages, so we'd better know what you want to do - or at least how much current you want to put across your junction at which operating temperatures.

Bye
Markus

 

[Otokoyama]

McGizmo, Thanks. In my particular case, that's too hot for the workpiece attachments, but might be an option in the future. Thanks.

 

[PsycoBob[Q2]]

Another option to add to Tomas' list: use a stove flame. I've soldered large copper chunks like this. If you can't heat the workpiece attachments, it won't help you this time.

 

[Slick]

I'm with Don on "baking my Luxeons... I use CW2400 extensively with outstanding results. I use a toaster oven that I switch between 150-200 to keep temps 160-170 and carfully monitor for 20 minutes using a Raytec 20 non-contact IR thermometer.

Conductivity improves as well as the epoxy being completly set and the part readied for the next assembly operation. The little widder was giving me the "evil-eye" but after I proved that NO noxious epoxy smells would taint the toaster, she was OK with it.. /ubbthreads/images/graemlins/smile.gif

For soldering on to large chunks of copper, I use paint-on flux and one of those "crack pipe" butane torches. It works great.