Crimps and crimp tool help

[nigelmercier]

I now use a very crude device like this...

Throw that one away, or only use it for stripping wires.

Most problems with insulated crimps are due to incorrect wire sizing, and incorrect loading. Look up the wire size and use the correct colour, double the wire if necessary. When the insulation comes to a stop, the bare end of the wire should protrude out of the crimped area by a couple of mm.

If you are convinced that your ratchet crimped is faulty, here is a good price for a Hilka:
http://www.amazon.co.uk/exec/obidos/ASIN/B003OV8J46/dolcetto-21

When I first bought my boat, I was of the opinion that insulated crimps belonged in Room 101, along with chocolate blocks. In my view the only crimps to use were the non-insulated type that roll the edges of the crimps over; or "ass cheek" as have been mentioned. I have since changed this opinion after a few failures, and now just buy good quality insulated crimps. Cheap ones are noticeably lighter, and are often shiny.

 

[chewi]

Really - I have one that looks identical to your failure and it seems fine after many years. Maybe unlucky.

+1
I have had several of those ratchet types for myself and mates, no trouble at all.

I wouldn't touch the 2nd "squeeze and hope" type.

 

[cliff]

The small item on the top handle with + and - on is a tension adjustment. Try moving it one notch to the + direction and give it a go on a crimp.

I have the same type of crimper.

+1

 

[David2452]

When I first bought my boat, I was of the opinion that insulated crimps belonged in Room 101, along with chocolate blocks. In my view the only crimps to use were the non-insulated type that roll the edges of the crimps over; or "ass cheek" as have been mentioned. I have since changed this opinion after a few failures, and now just buy good quality insulated crimps. Cheap ones are noticeably lighter, and are often shiny.

Never had a failure, not one, and that's from a sample of countless various types and numbers. if they are crimped as per the photograph, note the gradual lead in to the conductor crimp which assures no hard edge to damage the strands, thing is you will know if you have a bad crimp that will fail as you can inspect and do a proper pull test, (and in the future by sliding the cover back) if not right then one can snip it off, though I have not had failures I have had to re make them from time to time after inspection which only reinforces its importance to me. On the other hand I replace insulated types on a regular basis, almost always because of frayed strands, they may well have passed a pull test when applied but it is impossible to check for hard spots.

 

[nigelmercier]

... if they are crimped as per the photograph ...

Yes, but that was a huge cable compared with mine. They failed between the crimp and the spade.

 

[BERT T]

You will find a reasonable quality one here: http://uk.rs-online.com/web/p/cable-crimpers/4992313/?origin=PSF_412504|alt also buy the terminals from them as well. I've been using one for years and never had any problems.

 

[Dipper]

I found this excellent article a few years ago which explains a lot about crimping. If anyone is interested, read all four pages. http://www.pbase.com/mainecruising/wire_termination

I have a crimp tool like the OP's. Without this article, I wouldn't have known which way to insert the wire - they are unidirectional. As I found out, if you insert the wire from the wrong side, you get a very poor result.

 

[nigelmercier]

I have a crimp tool like the OP's. Without this article, I wouldn't have known which way to insert the wire - they are unidirectional. As I found out, if you insert the wire from the wrong side, you get a very poor result.

Being left handed, I have to start off with the tool upside down.

 

[Flossdog]

What does the team think about my standard practice when crimping? On smallish cables, I always run some solder into the wire strands before crimping. I believe that the crimp "bites" and holds better and gives a more durable end result.

 

[sarabande]

the only potential issue with some solders is the presence of residual flux, which is acidic.

 

[lw395]

What does the team think about my standard practice when crimping? On smallish cables, I always run some solder into the wire strands before crimping. I believe that the crimp "bites" and holds better and gives a more durable end result.

I am not sure why, but this practice is seriously looked down on in wiring shops.
I think because the crimp ends up with contact over less area.
On small wires, I often loosely crimp to fit the terminal to the cable, then solder.
But I don't pretend to be an 'airframe' wiring person.

 

[whipper_snapper]

What does the team think about my standard practice when crimping? On smallish cables, I always run some solder into the wire strands before crimping. I believe that the crimp "bites" and holds better and gives a more durable end result.

I would absolutely not do that. But I have in the past soldered after crimping, that can only help electrically and allows a proper hard metal contact in the crimp. I then back that up with very good physical support - typically an adhesive-lined heatshrink - because we are constantly told that soldering creates a hard point which can fail.


These days I mostly use Contralube and crimps on terminals. For wire to wire joins I use solder with heatshrink.

 

[Bilgediver]

Can anyone advise on a decent crimp tool? I bought one of these a while ago

It worked well for a while, but seemed to rapidly loose its gap settings and no amount of fiddling has got it right. I now use a very crude device like this:

Which sort of works, but it is awkward to get the crimp right.


Any suggestions for a decent and robust tool?


Also, any suggestions for a source of decent, marine quality crimps? Various places seem to stock various random combinations some tinned, some not. But ordering a good range from one place seems very difficult.


Thanks

Can t you adjust the closing pressure using the star wheel ???????

 

[JohnGC]

What does the team think about my standard practice when crimping? On smallish cables, I always run some solder into the wire strands before crimping. I believe that the crimp "bites" and holds better and gives a more durable end result.

A couple of problems;
- The solder wicks along the wire making it much less flexible adjacent to the crimp and prone to breaking if used in a position where flexibility is needed.
- The solder is soft and continues to deform slowly; more solder = greater deformation. This loosens the joint and increases contact resistance. If the joint carries significant current then it heats and causes the solder to deform quicker until the whole thing burns. I have seen this several times. NB the same thing happens with soldered wires in screw terminals and is worst on those without wire protectors such as the common "choc-block".

Crimped connections are very reliable if done well and don't need additional fixes.

 

[David2452]

Yes, but that was a huge cable compared with mine. They failed between the crimp and the spade.

Not huge though not tiny, just a blown up shot for clarity but the principle remains constant, the only real issue I have with that example is a possible strain relief one, I like to see, and the important word is "see" a much tighter crimp over the insulation.

What I really want is one of these.

 

[philip_stevens]

Can t you adjust the closing pressure using the star wheel ???????

Suggested in reply number 6.

 

[whipper_snapper]

Suggested in reply number 6.

And answered in post 10

 

[Leighb]

The small item on the top handle with + and - on is a tension adjustment. Try moving it one notch to the + direction and give it a go on a crimp.

I have the same type of crimper.

I have a similar crimper, however the star wheel appears only to have an arrow - anticlockwise, but no + or -, so I am not sure which way to move it to get tighter. Also the grub screw is in the lower (in the photo) of the two holes. Does this matter or does it give a finer adjustment?

 

[bigwow]

And answered in post 10

And commented on in post 9

 

[David2452]

I have a similar crimper, however the star wheel appears only to have an arrow - anticlockwise, but no + or -, so I am not sure which way to move it to get tighter. Also the grub screw is in the lower (in the photo) of the two holes. Does this matter or does it give a finer adjustment?

Adjustment depends on the crimp tool, with some of my crimp tools I have dies which fit the crimp area and on which one adjusts the pressure to calibrate it, I doubt those type are quite so precise and it's simply a matter of using any provided adjuster so that the stops meet before release when you insert a crimp with cable, so trial and error really.