Not sure if this is the correct place - but -  I have  neeeded to solder a P3 motor wire after a suspected dry joint.
I cut the wires to get fresh metal to  solder together.  And  the problems started!
The wires are as seen in the  motor windings - I assume  there are in fact  the tails of the same wire in the coils.  The problem is these wires do not seem to take to solder. I have  tried to "modern" lead free stuff and I have some really old - at least 30 years old - which contains lead - tried it and  this fails to "tin" the wires.

Does anybody have knowldge as to how and with  what, DJI repairs are carried out when motors need replacing

It may be that there is a varnish on the wire (clear). Try sanding a bit of the wire where you are trying to solder. That may help the solder to flow to the wire.

are they coated ?  like electroplating?  I had some like that once had to try and scrape the coating off grrr.. I prob gave up though haha, it was a long time ago

It will be like manddeb says, there is an insulating varnish on the wires, you need to scrape it off to bare the copper.

I just about guarantee what the others are saying is right.  Things like motor windings use wire that has a varnish (or similar) coating.  You need to use a knife to gently scrape that off before soldering.

It frustrated me as a kid until my dad looked at what I was complaining about, laughed, and told me about the varnish.

To be honest, it's a good idea to scrape or sand brand new uncoated wire to get any oxidation off.

im an electronic tech soldering for over 20 years you may have to tin the wires by a dab of solder on iron put to bare wires apply more solder till it tins  get flux it helps. Maybe get some fresh wire that you can solder to the motor and then the other into the board or practice soldering on wire til you get better I've Saturday everything from battery cables on Cars 2 micro circuitry in touch screen controller boards

For the electroplating that's on there heating up the ball of solder on the iron tip and running it will help melt the melt that off. In my experience they usually don't have that insulation on wire that has a rubber jacket already it's for stuff for motor windings and whatnot speaker wire but if you have to cut the rubber insulation off the wires are usually not insulated further

I can't speak for DJi Motors but I've had several other brands and when you strip the wire back you can solder right to it there was no additional coating but as I said I can't speak for DJI Motors

Electroplating???  It's called enameled wire, used internally on motors, speakers, most any electromagnetic device.  Scrape it off and solder without problem, but make it a good clean scraping so there's nothing but nice shiny wire to solder to (all the way around the wire, not just on one side of it).

AG0N-Gary Posted at 2016-10-10 12:32
Electroplating???  It's called enameled wire, used internally on motors, speakers, most any electrom ...

To All replies....thanks for  all your idea's and advice. The consensus  seems to point to a varnish on the wires..
It also explain some of the blackish burnt crud I thought was due to taking too much time with an hot iron  trying to tin the wires.
I will try scraping the wires a bit with a scalpel  and  report back...

use soldering paste to get a good soldering.just dip the tip of wire in it and then solder them

rr@jensen.mail. Posted at 2016-10-10 14:51
use soldering paste to get a good soldering.just dip the tip of wire in it and then solder them

I  did  use a liquid flux "pen" - and will look  in at  our local elictrical supllies shop to check on teh  paste.

For all the  other replies. I  scraped away at  the  wires with a sharp blade in  a scalpel,  what came off was not much and not sure if it was a varnish or surface copper  - but I did get some solder to stick on the wires.
and  torrow I will see if I can  improve this on another of the trio of wires the ESC.

Thanks again for all help and advice.

Quadcopter 102 Posted at 2016-10-9 23:04
I  did  use a liquid flux "pen" - and will look  in at  our local elictrical supllies shop to check on teh  paste.

For all the  other replies. I  scraped away at  the  wires with a sharp blade in  a scalpel,  what came off was not much and not sure if it was a varnish or surface copper  - but I did get some solder to stick on the wires.

May I ask how it went?  Were you able to get the wires back together?  If so, what did you do?

any luck ? I'm having the same problem?

Flux on scraped wires will work ,did it this weekend  was a bitch without it  burnt my fingers trying then hey presto ,worked a treat ,just flux didn't work so make sure you clean the wires up nice n sh.iny bare metal ,
Good luck !
ChEers Andy T

I've had luck burning that insulation off coated wire with a lighter.

Scrape of varnish .... tin .... solder ..... Done.

Nigel

One of the most important things you can do is to keep an eye on the temperatures. This includes the temperature of your soldering iron and the temperature of the joint itself. If either of these gets too hot, it can cause problems. Make sure you are using a soldering iron with enough wattage for the job and that you have a good heat

https://electronicshacks.com/how-to-solder-without-a-soldering-iron/

Amadjan Posted at 11-24 15:04
One of the most important things you can do is to keep an eye on the temperatures. This includes the temperature of your soldering iron and the temperature of the joint itself. If either of these gets too hot, it can cause problems. Make sure you are using a soldering iron with enough wattage for the job and that you have a good heat

You are replying to a thread that is 6 years old.