which way round to use ratchet crimping tool?

[Al Reynolds]

Hello,

I have now purchased this ratchet crimping tool:

am using it with these crimps: I wanted to know is: where do I use the tool on the crimps? I had originally assumed that the two sides of the jaw would both go on the central section of the crimp, but the two sides of the jaw differ. One has a "flatter" arch and the other has a more "rounded" arch.

I assume then that you use either use the tool twice (both ways round) on the central section, or once on each side of the crimp.

I have drawn a diagram showing what the two sides of the jaws look like. The picture is at:

instinct is that when crimping the (1&2) end of the crimp, the flatter (A) jaw should be at (1), and the more rounded (B) jaw should be at (2). Can anyone confirm or correct me on this?

Thanks in advance for your help, Al Reynolds

[Tim Mitchell]

In article , Al Reynolds writes

...

Yes, the wider part goes round the outer end of the crimp, where the wire insulation is. For butt crimps like you are using, you crimp twice, once for each wire, keeping the wider part on the outside.

[Peter Parry]

No.

No.

Yes.

On the diagram A appears to be rounder and B flatter so I'm not sure if you have you A's and B's mixed up in the description above. Using the diagram labelling the B (flatter) part fits at 2 and the A (rounder) part at 1. On the other end you put B at 3 and A at 4.

If you hold the tool in your right hand and insert the crimp from the left so the cable (at end 1 in your diagram) is in your left hand then the orientation is correct.

[Al Reynolds]

which is what you said - thanks for clarifying that.

One more question, now that we know which way round I should be working - how strong should a crimp be? For example, should I be able to pull it apart by hand? I read somewhere that the crimp should be at least as strong as the uncrimped cable, from which I would assume that I shouldn't be able to pull it apart.

TIA, Al

[Christian McArdle]

I always crimp 4 times, 2 for each wire. Paranoid, moi?

Christian.

[usenet]

I doubt if this actually makes the crimp more secure, with the correct tool for the crimp the tool is designed to squash the crimp just enough and no more. If you then do it again I think you're likely to damage (e.g. crack) the crimp and it certainly won't improve the connection.

[Christian McArdle]

I do the second one quite far from the initial crimp for this reason. A few quick tests have shown greater mechanical strength, if nothing else.

Christian.

[Peter Parry]

Not unless you indulge in weight lifting. The crimps do have pull apart figures. For some heatshrink sleeved crimps we use these are red: 25 lb; blue: 50 lb; yellow: 60 lb. The figures for crimps not incorporating heatshrink sleeving will be lower.

is a good article on crimp terminations and suggests the following "calibration" test -

"(1) Drive a finish nail into the front of your workbench. (2) Hang the terminal lug on the nail and tie a plastic 1 gallon milk jug of water onto a 22AWG wire (red terminals). For 18AWG (blue) use two jugs. For 12AWG (yellow) use three jugs. "

some more formal figures for insulated terminals and quotes:-

Wire Size Pull-out Force

20 AWG (0.50mm2) >/= 13.0 lbs (58 N) 18 AWG (0.75mm2) >/= 20.2 lbs (90 N) 16 AWG (1.5mm2) >/= 30.3 lbs (135 N) 14 AWG (2.5mm2) >/= 43.8 lbs (195 N) 12 AWG (4.0mm2) >/= 60.7 lbs (270 N) 10 AWG (6.0mm2) >/= 80.9 lbs (360 N)

[usenet]

On the crimps I use this would be impossible, one wire in each and and one squish at each end leaves very little of the connector unsquished.

[Dave Plowman]

If you check inside those crimps, you'll find they have a partition so the wires go in to the same length. And that partition won't deform to crimp anything - try it without any wire in one.

[Christian McArdle]

Sounds like my crimps are longer than yours! There's plenty of space on mine to double crimp without interfering with each other.

Christian.