Soldering Battery Connectors - RC Groups
Thread Tools
Feb 13, 2013, 11:53 PM
A Snickering Hound
Muddie's Avatar

Soldering Battery Connectors

I bought a couple lipos that came with no connectors, so I'll need to solder them on myself. My problem is that I have had near-zero luck soldering larger awg wire - I never seem to be able to get the wire hot enough so that the solder will freely flow. I use a generic 40W soldering iron.

My question is, does my iron have enough "ooph" to solder 12 AWG? I know my skills aren't the best, but it seems that something else is lacking for me to get such poor results with larger wire.

Any suggestions would be greatly appreciated!

Sign up now
to remove ads between posts
Feb 14, 2013, 12:10 AM
Sky Pilot
still4given's Avatar
Maybe your iron is not actually drawing 40 watts. I use a 40W iron with a chisel tip and it works well even on 10ga wire. You need to keep the tip clean and tinned. I feed a little solder right at the point of contact with the wire to help get the heat flowing into the wire. I then feed the solder at the tip of the wire so it can flow into the strands. It doesn't take long after that for the whole end of the wire to be hot enough to melt the solder all the way around. Give it a try.
Feb 14, 2013, 05:42 AM
A man with too many toys
Where is a good place to buy solder in the US - not the crappy lead free stuff!
Last edited by RC Man; Feb 14, 2013 at 07:05 PM.
Feb 14, 2013, 05:52 AM
Registered User
Greybird's Avatar
Radio Shack silver bearing solder works great. 62/36/2
Feb 14, 2013, 06:14 AM
Registered User
The key is to use a big tip with some thermal mass. Don't use a conical (pencil) tip. The other tip is to use a little solder on the tip to help transfer the heat when heating a connector.
Feb 14, 2013, 06:24 AM
Registered User
I agree, 60W or more is better, but 40W can do the job if it has a large enough bit so that it doesn't cool down the minute it touches the large copper wire.
Feb 14, 2013, 07:36 AM
Registered User
Get one of these and a chisle tip 40/60 solder and flux from Flea bay worth every penny,in this hobby soldering is a must.HK finally came through lol.
Feb 14, 2013, 07:42 AM
Registered User
Ohio AV8TOR's Avatar
Originally Posted by Ohmic
The key is to use a big tip with some thermal mass. Don't use a conical (pencil) tip. The other tip is to use a little solder on the tip to help transfer the heat when heating a connector.
+1 makes all the difference in the world and keep it clean
Feb 14, 2013, 10:16 AM
Frankenstein recycled packs
rampman's Avatar
For our hobby, just use the Radio Shack 60/40 rosen core lead based solder. We do not need the silver bearing type solder for 99% of our use in RC and it needs more heat than the lead based stuff.
IMO, buy this:
and this:
though you can buy shorter lengths than this. Trust me, larger diameter is better as it dispenses more flux per solder joint. More flux = better flow, better solder joint (in our use) and better cleaning.

Feb 14, 2013, 10:37 AM
Registered User
I tin first put flux on the unit then solder flows really easy,i use the smaller stiff and agree there's not enough flux,this way it runs like a charm.
Feb 14, 2013, 10:48 AM
Registered User
Always remember that FLUX is your friend
Feb 14, 2013, 11:03 AM
Registered User
As others have said a big tip on the iron is key. Flux doesn't hurt either. I'll agree with rick on the 60/40 rosen core solder. The silver bearing is only good if you add your own flux and it's really thin so for large gauge it's not ideal in my opinion.

Best solution though if you ask me, ditch the iron and get some Anderson PowerPoles and a crimper.
Feb 14, 2013, 11:15 AM
Pro Bro #1963
What type of flux are you guys using when doing electrical soldering with 60/40 solder from Radio Shack for example?

Feb 14, 2013, 11:32 AM
Frankenstein recycled packs
rampman's Avatar
See my link above.
Rosen flux.
Do NOT use no-clean.

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Which soldering station will be enough to solder batteries esc & motor connectors? ath512 The Builders Workshop 29 Sep 25, 2017 02:39 PM
Question Best way to connect motors and ESC's: Use solder or bullet connectors? 2MacGyver Multirotor Drone Talk 30 Mar 20, 2017 08:53 AM
soldering battery connectors _Lunchbox_ Batteries and Chargers 19 Aug 25, 2005 12:24 PM
Soldering connectors on batteries dacaur Micro Helis 3 Jun 23, 2005 12:43 AM