pre-assembled short wires with ring terminals on one or both ends?

Discussion in 'Electronics Resources' started by ue418, Jul 10, 2010.

  1. ue418

    Thread Starter New Member

    Jun 22, 2010
    17
    1
    Does anyone know where I can easily obtain some short (6, 7 or 8 inch long) wire (maybe 20 thru 26 AWG...not too important) that comes with ring terminals already attached? Perhaps only on one end, although I may also need wire that has an F1 terminal (spade) on one end and a ring terminal on the other. Is there a term I'm not aware of for this sort of thing? I'm not able to find anything, except for one "harness" on a Chinese site, that required bulk ordering. I really don't feel like messing with trying to find a crimping tool that works, and I've never had much luck with crimping. So I would rather purchase something prefabbed.
     
  2. Ghar

    Active Member

    Mar 8, 2010
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  3. sceadwian

    New Member

    Jun 1, 2009
    499
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    In a pinch you can use a pair of plyers. The chances of you finding pre-made wires of this type are slim to none for the simple fact that crimping is not that complicated. If you've not had success before then now is the time to figure out what you're doing wrong and learn how to crimp simple connectors properly. It's crusing metal contacts against wire in some way that you attain a good ohmic contact. If you don't like your contacts, the solder them afterwards and you'll be nearly bullet proof electrically speaking.
     
  4. someonesdad

    Senior Member

    Jul 7, 2009
    1,585
    141
    I agree with the others -- you won't find anything ready-made, although you can easily find people who will do the work for you. However, they'll likely charge you a bunch of money for what is pretty trivial work that you can do yourself. If you like, I have a friend in California who owns an electronics business and I'm sure he'd be willing to take your order and do the work. But he'll charge you 10 to 100 times the cost of what you can do it for yourself.

    Nearly any tool store will have pliers that can be used for this task. Here's another kind. I like the ratcheting kind that won't let go until the crimp is completed, but in a pinch you can use almost any kind of plier. Sometimes I'll just crush the solderless terminal in my vise. The key to a good joint is crushing things enough to get plastic flow of metal.
     
  5. Potato Pudding

    Well-Known Member

    Jun 11, 2010
    684
    92
    Crushable means either flimsy or you need to use lots of force.

    With high leverage multiplication that would mean a wide grip on your pliers while open.

    You better have big hands.

    With lower leverage you would need a very strong grip.
    Arthritis for example would make this difficult.

    Also very possible -especially using lighter guage wires is that the terminal is getting crushed too much and the copper wire inside being weaker is getting cut off so that the wire and terminal connection falls apart. This is especially easy to do with poor quality terminals made from alloys too hard and brittle for the job. These tend to crack as they are bent and crushed and leave lots of sharp edges that will cut the wire.

    I agree with finding out what the problem is that is making crimping a problem. It is often the basics that cause the most problems and not just for those just starting out.

    One tip that I am not certain has been mentioned. Tin your wires before you put them in the lug and crimp. That will make things much easier whether you plan to add solder later or just crimp and use.

    It takes a few extra seconds for each wire to get tipped with some solder. It makes success much simpler when you are crimping.
     
  6. Ghar

    Active Member

    Mar 8, 2010
    655
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    The problem I see mentioned with tinning before crimping is that the wire thickness now becomes different and there's a very loose filler since solder breaks apart.
    If the wire is too thick for the terminal it won't crimp down properly. This isn't an issue if you're using wire smaller than the maximum specified for that terminal though, giving you room for the solder.
     
  7. sceadwian

    New Member

    Jun 1, 2009
    499
    37
    Tinning doesn't effect wire thickness significantly. It also doesn't act as a filler as a properly heated solder joint forms a metallurgical bond at the surface of the metal and the solder, the boundry layer actually becomes an alloy. The tin itself is beneficial because it drops the coefficient of friction of the wire so much that it allows it to be crushed properly, a bare naked copper wire with the pre-requisit thin oxide layer will tend to crumple and make poor direct contact, where as a tinned copper wire will flow very well into a good ohmic contact.

    If you're tinning your wire and it's acting as a 'filler' you're tinning it wrong with either too much solder or the wrong temperature with a dirty copper surface and/or no flux.

    Don't confuse bad work with an improper process. Proper tinning before a fresh crimp will result in a superior joint, and that's without soldering afterward. Soldering such a crimp after a tinning will provide the ultimate in low ohmic contact.

    Copper is an awesome conductor, it is also a highly reactive metal, and will oxidize from an active state in the less than the time it takes to read this post in free air. Oxides are bad, tin has unique properties which although it's still a relatively active metal makes it's ductility superior for surface contacts. This is also why gold is often used for electrical contacts. It tends to remain active even in a corrosive environment an will form a surface bond with other gold connectors that rivals that of anything you can get with tin, it however doesn't solder well at all, which is why it's used for gold on gold contacts for connectors.
     
    Last edited: Jul 11, 2010
    Ghar likes this.
  8. Ghar

    Active Member

    Mar 8, 2010
    655
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    Interesting, I haven't personally done that much crimping it's just some bit I came across at some point.
    This makes the tinned mil-spec wire I have make more sense too.
     
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