Soldering a flex cable

[MG1234]

Need to solder the end of a flex cable I just got for my Spartan ,it slipped in 1 minute ,super tight ,I can solder plumbing And electrical wires but I can't get solder to stick to the flex cable ,I'm using typical plumbing torch,flux,sand cloth ,lead free solder,got it all cleaned up but my solder dosent really build up ,my only other idea is to use the silver solder I use on wires ,any tips please?

[iridebikes247]

Hmm, well you probably already know this but make sure its really, really, really clean. Use a torch then clean with acetone, run this process a few times then you're ready to start. The thing is it sounds like you've already used this cable meaning grease has gotten on it, this makes soldering a flex much more difficult, and sometimes its almost impossible to get it to stick.

I would use a basic 60/40 from radioshack, and just some flux. This will work without question, I have soldered around 30 cables using this no problem. You can use a powerful soldering station or a torch. Thing is the solder melts at a low temp so get the cable hot but not too hot, it'll never stick if its scorching. I would give it a few more tries if anything, I think OSE offers an upgrade spartan cable, and I know for a fact the cables Steve stocks soak up solder no problem. Hope this helps!

[MG1234]

Thanks ,I have one ordered from wholts but it's not here yet so I stuck on a new sock one ,Ted it was greased,cleaned with gasoline ,sanded ,but I think your right the grease has permitted way in ,I'll try again tomorrow and clean better and use a different solder ,

[iop65]

@MG 1234:i suggest buying another coupler and not soldering the flex

never had issues not doing that

in fact when heating the flex above a certain point ( with a torch) the metal becomes brittle

[martin]

Ive soldered the flexes or brazed them many times in the past, I no longer bother as I find theirs no problems with the flexes providing their prepped correctly with a nice bevel ground on the end. Also you must always rotate the flex clockwise when pulling flex out of the coupling or inserting flex back into coupling, this prevents the flex from snagging & unwinding.

[iridebikes247]

I had problems with flexes spinning in the collet when using big props in high power setups.

Seems like you ran into the same problem quickly, definitely solder it. Of all things that can become a problem at the lake, this is one of those things that should never fail. A flex should be idiot proof and soldering it is the best way of ensuring that it never causes a problem, again. No special removal required. The metal will not become brittle when heating it, too much heat and the solder will never stick so you'll need to find that balance.

[kfxguy]

Most importantly, did you clean the end of the cable as it went into the coupler? Think about the grease you just pushed it through. Then that grease go in the collet making it harder to grip. Once you strip a flex you need to replace the collet too. It likely messed it up also.

[MG1234]

Thanks my new one just came in with a new coupler so I'll take the time to install them ,I did get the wire red hot ,