How does crimping work?
in [Repair]
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From: F Murtz on 1 Dec 2009 05:52 Dave Plowman (News) wrote: > In article > <b06cb5a9-8c0d-4d8e-a980-5ddef60712af(a)p19g2000vbq.googlegroups.com>, > whit3rd<whit3rd(a)gmail.com> wrote: >>> Depends on the use. I'd say the most common crimp terminals are in some >>> form of spring loaded contact. And those tend to be made of brass > >> Phosphor bronze or beryllium copper are the springy metals in common >> use (it may LOOK like brass...). > > Could well be - I've not had it analyzed. But it certainly doesn't look > like copper. ;-) > Of course it could be all these sort of things are copper in the US. I can > only speak for the ones I'm familiar with in the UK. > Spade connectors have to have different properties to lugs because they rely on spring tension for electrical continuity but proper bolt on lugs are usually copper for copper cables, aluminium for aluminium cables. http://www.zeetaelectricals.com/
From: Michael Kennedy on 1 Dec 2009 07:13 "Dave Plowman (News)" <dave(a)davenoise.co.uk> wrote in message news:50c291ea81dave(a)davenoise.co.uk... > In article <d3n8h59kal7te33ioo1jkvrnetlcfjtqd1(a)4ax.com>, > PeterD <peter2(a)hipson.net> wrote: >> >> Cite a reference. >> > >> >Try cutting one open. > >> That tells you nothing about the metal... Again, cite a reference. > > Do you know the colour of copper? > > -- > *Forget the Joneses, I keep us up with the Simpsons. > > Dave Plowman dave(a)davenoise.co.uk London SW > To e-mail, change noise into sound. Good grief... Cite a reference.. How is a reference better than actually having the item in hand. I say the reference is any piece of equipment that has crimps in it. Anyhow.. Someone happened to cite the needed info..
From: Sylvia Else on 1 Dec 2009 07:28 Sylvia Else wrote: > The obvious answer is that you bend the metal of the connector so that > it holds the wire in place. > > This doesn't seem very satisfactory. Metal always retains some > flexibility, even when bent beyond its yield point. No matter how hard > you squeeze, there'll be some rebound when you release the pressure, > which should result in a loose joint. > > After having had a bad experience trying to crip a lug some years ago, I > recently faced the need to do this again. So I bought a moderately > expensive ratchet based crimping tool. And, rather to my surprise, it > actually works. > > But that doesn't answer the question of how. > > Sylvia. BTW, I'm seeing huge variation between lug types (same colour - different brand). I bought some fully insulated ones - and could pull them all off with no difficulty. The ones I had in my stock from way back either failed by tearing the conductor - or had a strength exceeding mine, and didn't fail. At least there was some consistency - lugs out of the same box performed the same as each other. The crimping tool has a 'pressure' setting, but comes with no guidance on how to decide which pressure to use. Sylvia.
From: kreed on 1 Dec 2009 07:31 On Nov 30, 10:54 pm, Sylvia Else <syl...(a)not.at.this.address> wrote: > The obvious answer is that you bend the metal of the connector so that > it holds the wire in place. > > This doesn't seem very satisfactory. Metal always retains some > flexibility, even when bent beyond its yield point. No matter how hard > you squeeze, there'll be some rebound when you release the pressure, > which should result in a loose joint. > > After having had a bad experience trying to crip a lug some years ago, I > recently faced the need to do this again. So I bought a moderately > expensive ratchet based crimping tool. And, rather to my surprise, it > actually works. > > But that doesn't answer the question of how. > > Sylvia. The ratchet tool provides substantial mechanical advantage compared to many of the cheap tools, and therefore enormous pressure on the joint. With the right tool, the joint is squashed down by the exact amount, whereas cheap hand tools are more "hit and miss" as to whether you have applied the right pressure to them. the "die" is also a lot better on ones that I have seen, and probably designed to put the pressure in the exact right places at the right time during the crimp. (ie, more efficient use of the energy you apply with your hands) As the metal parts of the surface being crimped are squashed really hard by the tool, they probably heat up (compression causes heat, and metals expand with heat,), and then shrink as they cool, tightening on the wire ?.
From: PeterD on 1 Dec 2009 09:08
On Tue, 01 Dec 2009 00:47:44 +0000 (GMT), "Dave Plowman (News)" <dave(a)davenoise.co.uk> wrote: >In article <d3n8h59kal7te33ioo1jkvrnetlcfjtqd1(a)4ax.com>, > PeterD <peter2(a)hipson.net> wrote: >> >> Cite a reference. >> > >> >Try cutting one open. > >> That tells you nothing about the metal... Again, cite a reference. > >Do you know the colour of copper? OK, so clearly you don't have a clue, no evidence or facts to base your lame assertion on, so... |