I cant solder a wire

[TurboRA28]

Howdy, I am trying to solder together the wires to my wideband 02 sensor. They got ripped/snapped off.

For some reason the solder will not take at all.. I'm normally an alright solderer but not this time. Putting shitloads of heat into the wire and heaps of solder but none will stay on the wire.

Is there some weird arse wire that normal lead/tin solder will not bond to?

Any ways around this?
Thanks
Joel

[brett_celicacoupe]

try dipping the wire in some acid to clean off any surface residue. the resin core solder just might not have enough strength to clean it. HCl acid is the ideal IIRC

if the breakage occured close to the O2 sensor then id be wary of just soldering it. heat may conduct down the wire and soften the solder. it really doesnt take much to soften that stuff

[sideshow]

hey joel

o2 sensor wires are stainless i think

just get the iron very hot and just keep adding solder it should eventually stick

or if theres room just crimp wires together

[TurboRA28]

Thanks for the suggestions all.. Yeah I was thinking it might be best to crimp the wires together as they snapped off right on the sensor, so i had to cut a bit of the end away to expose some wire.

Reckon jaycar would sell some crimps to hold them together? Would have to be a metal/slim crimp of some sort not enough room to get like spade terminals or anything on.

[Bananaman]

Hey mate,

Forgive me if this is a bit of a basic statement, but if ever i'm doing something thats particularly difficult, i make sure that theres a thin coating of solder on the section you're actually touching to the wire to heat it up, i find it makes a massive difference in conducting the heat quickly as opposed to a dry iron for example. You probably already know/do this, but just in case

-Bardin

[oldcorollas]

steel and stainless can be a bitch to solder to... if you have a pot of that flux (that i can't remember the name of and am not sure it is still sold), it works well
if you can roughen the wires up a little, that could help with the initial tinning, esp if there is a thin oxide layer on the stainless wire (which there always will be)

[JustCallMeOrlando]

As Stew said, failing having a pot (which tends to eat any contaminants), give it a rough up with some wet and dry, should etch the surface slightly and remove any crap on it. Then get the iron nice and hot. Try to tin the O2 sensor and the wire, then go from there.

Your idea of crimping though probably has merit, even if you use a little bit of solder to help secure it.

Without knowing exactly what we're dealing with, that'd be my best/simplest approach.

[thechuckster]

jaycar might have some smaller header pins/sockets- similar to motherboard power connectors - but am not sure about heat resistance. Ampolex make auto-grade stuff - but is too is a bit bulky (not to mention expensive).

Maybe recycle the power connector and power lead off an old hard drive?

fwiw, i found the wires in the bosch narrowband O2 sensor (4 wire) that i got from oldcorollas also diffucult to solder.

solution? twist strands but not too tight, dunk in metho and allow to dry (air blowing will do) then dunk in small container of baker soldring fluid an allow to 'soak' up into wire strands, then straght after removal, apply heat from soldering tip that has some residual solder but no burnt-off flux, fluid will boil off and a bit of the solder will transfer, then add more fresh solder to the point where the wire/tip meet.

.. but if the wire snapped off at the sensor, you'll probably find normal solder will weaken from the nearby heat.

[oldcorollas]

i think it's YORK brand?

the other thing you could try is to use a pencil gas torch instead of a soldering iron...

for auto wires, which tend to be a little bigger, i often use either a proper gas pencil torch, or sometimes just a "jet lighter", because they get heat into the wire quickly, and combined with soldering paste/fluid, tend to burn off the crud..

or it could melt everythign around it

[Draven]

I tend to go for the industrial size "spade" soldering iron for these sort of jobs. 0 guage wiring? no problem!

stu's jet lighter idea has merit, I never thought of that....

[StuC]

ah, the snap-on butane soldering pen thingy.go get yourelf one. works a treat.

[Scorpion]

If you go to Jaycar or Dick Smith ask to see some Molex connectors.
They're quite small and they used to come in a strip. They are the connectors you can solder into a circuit board to create your own integrated circuit socket. You could solder your wire to the part that goes into the board and the other end should slip over your O2 connection. They could possible dislodge if someone knocked the wires later when working on the engine so I'd put some heatshrink over them when connected or at least some tape.

The other way is to get any slip on connectors like internal power connecors from an old computer and take the metal pin/sockets out of their plastic casing and use them.

[Cool1]

o2 sensor wires are stainless i think

Aluminium coated copper!

[MFN-MAN]

I know i have no technical knowledge and this is probably a silly idea, but wouldnt it be easier to source and install another 02 sensor/wire if you're having so much trouble with it?

[roadsailing]

use a screw down terminal connector, i don't think a crimp will hold on too well.