[jasonb]

Not sure if this is the right sub-forum to post this in, so sorry if it isn't.

Looking for suggestions on the right soldering iron for making a headphone cable. Basically what I want to do is chop up an oem AKG 3.5mm to mini XLR cable and make it shorter, much much shorter. It's going to be for a K371 to a Qudelix 5K which will be attached to the K371.

So the plan is the cut a large section out of the cable, and solder the cable back together, only much shorter and then cover the connection with heat shrink tubing to seal it and strengthen it.

So what would be the type of soldering iron and solder I need for these very small gauge headphone wires?

For picture reference I want to do what's in this picture but hopefully a bit cleaner.

 

[JohnSD]

Any type of soldering iron and solder should work even if you have a larger tip it can be done carefully.

It would be easier to just cut the cable to the correct length keeping the mini xlr and installing a new 3.5mm at the other end.
Removing a chunk of cable and re-connecting it like you propose is much trickier.
Since youi have extra cable length you can get some practice in and see which method you like better.

 

[jasonb]

Any type of soldering iron and solder should work even if you have a larger tip it can be done carefully.

It would be easier to just cut the cable to the correct length keeping the mini xlr and installing a new 3.5mm at the other end.
Removing a chunk of cable and re-connecting it like you propose is much trickier.
Since youi have extra cable length you can get some practice in and see which method you like better.

You may be correct. I'd just have to also order a 3.5mm plug too. But that can't be too expensive I'd imagine.

As for the soldering iron I'm just wondering what kind of wattage and heat would be ideal for small wires and tight spaces.

 

[JohnSD]

You are working with relatively small wire and parts so I cannot imagine any soldering iron that would be un suitable, its when you get to things like fat metal binding posts for speakers that you need to up the wattage. Just keep your contact times pretty short- less than 3 seconds and you will be fine.

And if you have not done this before get some practice in with the unused wire you are throwing away.

 

[jasonb]

You are working with relatively small wire and parts so I cannot imagine any soldering iron that would be un suitable, its when you get to things like fat metal binding posts for speakers that you need to up the wattage. Just keep your contact times pretty short- less than 3 seconds and you will be fine.

Gotcha. The end that is on the green cable in my picture isn't a solder on end, it has screws that you clamp the 3 wires around. I've actually soldered stuff before, but I don't have my own soldering iron and need to get one. So anything with a small tip should be fine?

 

[JohnSD]

Correct, anything with a tiny tip or even a medium tip....if you are steady even a large tip could work in a pinch.
You can get a 3.5mm solder connector almost anywhere, make sure the exit cavity is larger than your cable diameter for a clean install.

Also probe the cable AFTER you cut to confirm the pinout. After the cut you will have a 3.5mm on one end, probe the wires to see which color wires connect to tip, ring, sleeve and when you put the new one one keep those connections the same.

 

[jasonb]

Gotcha. What id really like to find to make this super clean and more compact would be a 45 or 90 degree mini XLR end so the XLR end didn't stick so far down but I've yet to find one.

 

[JohnSD]

Yeah that would be nice, not sure if any exist either, they have them for full size not sure if for "mini" or Neutrik calls them "tiny" XLR.
Easy to find for 3.5mm though.

Another trick is to not use the boot on the mini xlr. Use 3:1 adhesive lined heat shrink and maybe first encapsulate the connections with a resin like epoxy.
When you apply the adhesive type heat shrink and it is still hot you can bend it and it will hold its shape after it cools. Doing this you can fake a right angle connection.
This gives you a makeshift strain relief. A 3:1 adhesive lined heat shrink is going to be quite strong- its not floppy like standard 2:1 heat shrink.

 

[jasonb]

Yeah that would be nice, not sure if any exist either, they have them for full size not sure if for "mini" or Neutrik calls them "tiny" XLR.
Easy to find for 3.5mm though.

Another trick is to not use the boot on the mini xlr. Use 3:1 adhesive lined heat shrink and maybe first encapsulate the connections with a resin like epoxy.
When you apply the adhesive type heat shrink and it is still hot you can bend it and it will hold its shape after it cools. Doing this you can fake a right angle connection.
This gives you a makeshift strain relief. A 3:1 adhesive lined heat shrink is going to be quite strong- its not floppy like standard 2:1 heat shrink.

Interesting