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Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: Duncan R on 14.10. 2011 14:03

Title: Soldering Lucas style bullet connectors
Post by: Duncan R on 14.10. 2011 14:03
Hi All,

I am in the process of sorting my wiring out. As I am a novice solderer can anyone advice the best method of soldering the bullet connectors?

Many thanks

Duncan
Title: Re: Soldering Lucas style bullet connectors
Post by: Gonemad on 14.10. 2011 14:48
What I did, when I did it many years ago, was to countersink the tip of the bullet and then splay the individual strands of the wire out into the countersunk area.  Then just heat the tip of the bullet, and the wires of course, and touch the solder wire to it. You will get a good connection but more importantly the bullet will stay on the wire when you pull it back out of the bullet receptor at any time.

If you have a lot of bullets to countersink you can hold the countersing bit in a vice and the bullet in a drill chuck.  If you have the bullet tip flush with the chuck jaw tips you will get the depth that you need without ruining the bullet when the countersink bit snatches on the soft material of the bullet, as it will.

Trim the wire that you want to solder in place such that the outer plastic will fit inside the bullet when the inner wire only just protudes proud of the bullet tip. If the situation allows it, it can be very handy to lightly grip the wire and bullet with a pair of static Mole Grips, for example.  Otherwise you will have a difficult job trying to hold the wire, solder and soldering iron all at the same time.

Good luck,

Angus
Title: Re: Soldering Lucas style bullet connectors
Post by: Duncan R on 14.10. 2011 14:58
Hi Angus,

Thanks very much - I will give that a go, I don't have a vice but I think I will be able to countersink the tip by hand as they are only soft brass. Do I  partially cover the bare wire in a thin layer of solder before passing it through the hole so the solder melts inside the bullet as well?

Regards

Duncan
Title: Re: Soldering Lucas style bullet connectors
Post by: iansoady on 14.10. 2011 14:58
Soldering is easy if you do it right and a nightmare otherwise. The vital thing to remember is that the thing you're soldering must be hot enough to melt the solder otherwise you're just "sticking" the things together. A good solder joint will last for ever. So....

1. You need a decent electric soldering iron - I have a 35 watt one which is fine for this job - and multicore colder. If you can find the old lead/tin stuff that works best. Let the soldering iron heat up fully.

2. Strip the end of the wire for 5/16" or so and twist it using your fingers. Make sure it's bright and shiny.

3. Apply a little solder to the end of the iron so it flows over the surface - this is called tinning. I always flick any surplus off hence have little holes in my shirt.....

4. Apply the iron to the shiny cable from (2) for a few seconds then touch the multicore to the cable next to it. The solder should flow into the strands and look bright and shiny. If it doesn't work straight away don't try for too long as the insulation on the cable will start to melt.

4. Put a bullet connector flat on a piece of wood, hold the soldering iron on the outside for a few seconds then feed multicore into the open end. You'll feel it go soft and melt till it fills the bullet.

5. Still holding the iron on the outside, feed the end of the cable from (4) into the nipple till you see it just appear at the small hole.

6. Remove the soldering iron and hold the cable & nipple all absolutely still till the solder solidifies.

If you have any problems getting solder to flow, it's either not hot enough or there are traces of grease around - get rid of this with switch cleaner.

And now we'll be told we should crimp them - but I've been soldering for 40-odd years and had virtually no failures.
Title: Re: Soldering Lucas style bullet connectors
Post by: Duncan R on 14.10. 2011 15:21
Many thanks Ian
Title: Re: Soldering Lucas style bullet connectors
Post by: Gonemad on 14.10. 2011 19:47
Hi Duncan

It is a good idea to 'tin' the wire with solder before you put it into the bullet.  That will certainly allow the solder to flow completely.  After tinning, when cold, see that the wire does indeed still go through the bullet completely.  A small file will remove any little bumps or drops that may have developed.

As Ian says, use a hot iron but.... do not keep it on for too long or you will burn the insulation rubber on the wire.  It's a balance, too cold and again as Ian says you will only stick the two sufaces together and get what is called a dry joint which may not connect for current flow.

You are quite right in that you can countersink the tip by hand, it just takes a few moments longer.

Use a bit of spare wire, two bullets and a receptor and practice with a volt meter.  It's easy.  You will soon be doing a fine job.

Good luck again

Angus.
Title: Re: Soldering Lucas style bullet connectors
Post by: Duncan R on 14.10. 2011 20:44
Hi Angus,

Thanks , I will have practice. I have a pointed tip on the iron I have , is it better to have a chisel type? the solder seems to drop off the pointed tip.
Title: Re: Soldering Lucas style bullet connectors
Post by: iansoady on 15.10. 2011 10:34
Hi Angus,

Thanks , I will have practice. I have a pointed tip on the iron I have , is it better to have a chisel type? the solder seems to drop off the pointed tip.

Chisel point is usually better as you get more contact. You probably need to clean the tip up with a file (till it's bright & shiny) as it will have oxidised. I have a tin of Fluxite paste flux which is many years old but ideal for getting a good clean surface. It's still available.
Title: Re: Soldering Lucas style bullet connectors
Post by: Duncan R on 15.10. 2011 13:31
Thanks Ian,

I will get a chisel tip and some flux.

Regards

Duncan
Title: Re: Soldering Lucas style bullet connectors
Post by: Duncan R on 19.10. 2011 11:22
Hi Angus and Ian,

Thanks for your advice - all soldered up now , no more twisted together wires with tape over them!

Regards

Duncan
Title: Re: Soldering Lucas style bullet connectors
Post by: A10Boy on 19.10. 2011 12:47
I use a piece of wood with a small hole drilled into it - not right through - to stand the bullet in, it makes it easier to hold and heat.
Title: Re: Soldering Lucas style bullet connectors
Post by: Duncan R on 19.10. 2011 15:23
Thanks Andy - I will keep that in mind
Title: Re: Soldering Lucas style bullet connectors
Post by: Mosin on 23.10. 2011 21:41
There are some absolutely excellent instructional videos on youtube on just this subject. This one:

http://www.youtube.com/watch?v=MnldHRtjre8  (http://www.youtube.com/watch?v=MnldHRtjre8)

is particularly good, once you get over the guy's inexplicable habit of completely ignoring the letter "L" in the word "soLder"!