Announcement

Collapse
No announcement yet.

OT removing layer before soldering

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • OT removing layer before soldering

    The layer being probably a combination of rubber and oxides. The older an extension cord gets, the more likely that the copper will tarnish and be hard to solder. I'm trying to put some ends on, but this stranded wire is not responding to the flux, nor to the liquid flux that I'm adding. I'm having to use a mechanical method of cleaning all the strands so it will take solder. Purple scrubbie seems to work, but it would be good if I could just dip the end of the wire in something, then solder normally. The 'something' would vanish after it does its job, of course I don't want to create a corrosion problem waiting to happen- acid flux might do the job, but then acid will become trapped inside the insulation.

    Do I mix up some Tang and dip all the stripped ends in it for a while, or do I use ranch dressing- or oil and vinegar perhaps? Will vinegar bring out the fresh copper?
    I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

  • #2
    Rubber sticks on and leaves a "goo" even when it appears to be gone. It's a problem. I have had fairly good results with what is left of a tube of bow rosin (for violin etc) that I picked up when cleaning out and doing some work at a facility that had been a music school.

    Mechanical methods seem to be best, followed by the rosin.

    1601

    Keep eye on ball.
    Hashim Khan

    Comment


    • #3
      Vinegar will work if it's just corrosion. Let it sit until you've got bright copper, might be worth following with a dunk in some baking soda solution or wonder to make sure the acid is neutralized afterwards

      Comment


      • #4
        Vinegar with a bit of salt will clean tarnished copper.

        Comment


        • #5
          I use X-fine sandpaper: 220 - 500 grit. Then flux.
          Paul A.
          SE Texas

          Make it fit.
          You can't win and there IS a penalty for trying!

          Comment


          • #6
            I will try some things-
            I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

            Comment


            • #7
              I would be worried that vinegar would wick back "up" the conductor and not be entirely neutralized by the baking soda. Such that it would very slowly erode the conductor, increasing its resistance, and getting hot enough to do damage. And you'd never know until it was too late.

              Comment


              • #8
                I might try Rubber Renew if I still have any. Not sure what's in that but it's nasty. Or methylene chloride, pretty nasty also.
                I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                Comment


                • #9
                  Rubber Renew does nothing, no methylene chloride here (just as well) StripX does nothing, but apparently it can strip enamel from magnet wire.

                  I'm playing with a different wire now- same problem. This is shielded cable- the center conductor solders fine, the shield does not. I know it's copper- if I worry it to death the silvery coating will come off, but this is too labor intensive. Maybe I should try electrolytic de-coating. What do I need- negative on the wire, positive in the salt water?

                  Throw the wire away? This is a good quality wire, used in test equipment in an electrical factory making distribution transformers, etc. I'd like to be able to re-use it, but maybe it's not worth the effort.
                  I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                  Comment


                  • #10
                    Update- that had to be one of the fastest tests I've ever done. Stainless cup, water with a bit of table salt in it. Positive to the cup, negative to the wire. I used a current source at a 100 ma setting, watched the bubbles rise for 10 seconds or so, then dried it off. Now it solders just fine. What a difference! Well now I know-

                    I think I'll test this again using more time. I want to see if the silvery color will come right off.

                    About three minutes in, no copper showing yet. Now I need to see how short a time I can use and still get good soldering. Back in a sec- ok, 5 seconds and it still works. Am I being fooled by something here? I'll try it with just salt water, no current. Ok, that's a no. Water only, 15 seconds, 100 ma- I can tell it's better, but not nearly good enough.

                    So that's it, dip the shield wire in salt water for 5 to 10 seconds with 100 ma. I'm almost blown away how well that works. Me happy camper.
                    Last edited by darryl; 06-30-2020, 01:18 AM.
                    I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                    Comment


                    • #11
                      i thought the problem was the rubber.

                      Comment


                      • #12
                        Originally posted by dian View Post
                        i thought the problem was the rubber.
                        Mostly it is. Flux will not affect the rubber, but will deal with the corrosion.
                        1601

                        Keep eye on ball.
                        Hashim Khan

                        Comment


                        • #13
                          Originally posted by darryl View Post
                          Update-... Stainless cup, water with a bit of table salt in it. Positive to the cup, negative to the wire. ...
                          Instead of salt, I would use washing soda or baking soda. The salt water will surely wick up the conductor & hide there, corroding the wire.

                          Comment


                          • #14
                            I've done the same, only using baking soda instead of salt. Dunno if it was the best way, but it worked

                            Comment


                            • #15
                              Ok, baking soda it is. And I'll need a holder for the (tapered) cup so it doesn't tip over on the bench.

                              This wire that I tested with is rubber covered- unknown whether the rubber has migrated to the wire, causing the problem. The extension cord wire is rubber covered, and that's twice- once for the individual conductors, and once for the overall sheath. Both types of wire have conductivity before any cleaning of the bare wire takes place- I don't have to scrape anything off before a contact can be made. That tells me that the surface of the wire will react when current is flowing through the salt water. Next time I'm stripping extension cord wire to make connections, I'll try this electrolytic 'trick' on it, and report my findings. It worked so well on the shielded wire- I expect it will work on the extension cord wire too.

                              I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                              Comment

                              Working...
                              X