Connector question

[alistair.howie]

I have a trex 550e with stock ESC and a CC BEC Pro. I also have the Spektrum DX8 telemetry unit.

I was about to try to start soldering XT60 connectors to my battery and esc and have discovered that I can't fit the ESC and BEC pro wires into the "cups" on the XT60 because the combined diameter of the wires are too great. And that's before I even tried including the (admittedly small) telemetry wires to measure flight pack voltage. Also, I'm sure putting 3 wires into a single connector probably isn't best practice!

I'm completely new to this hobby and so would appreciate some advice on how to connect all this up. I'd like to use the XT60s if possible because I hear good things about them, and being new to soldering I've heard they are easier than Deans. Not sure if I need to rig up some sort of harness, or just up the connector size and put the three wires together.

All advice gratefully received.

Thanks

[xygax]

That's easy the esc is the biggest consumer of current so it needs the biggest cables. The bec won't take more than a couple of amps ant the telemetry next to nothing. So use thin wires on the bec and together with the telemetry cables wind them round the esc cable just above the connector push the heat shrink on all three cables together and then solder the whole thing to the connector and shrink. It's a bit cumbersome but doable
Steve

[alistair.howie]

Thanks for the advice, Steve. Just to check my understanding ...

You say use thin wires on the BEC - it already comes with wire attached - 16 GA is says (guage?) - with a soldred end. Similarly with the telemetry unit (much thinner guage). Are you suggesting I cut the ends off to expose the wire strands of both, then twist them all together just above the connector? If so, I guess I should tin this twisted bundle to hold it together, rather than just relying on twisting and shrink tube to hold it, right?

[xygax]

Yes when you solder the bundle to the xt60 keep the joint hot and let the solder do it's Job

[alistair.howie]

OK, so I tried the soldering last night. A complete disaster! There were a few problems that I can see:

Because the ESC and (to a lesser extent), the BEC Pro wires are pretty thick, I couldn't easily do a neat job twisting the wires together. Ended up looking like a botch job. However, I persevered and tried soldering it. I was using a 48W digital soldering iron with a sufficiently large, tinned chisled tip. Was also using Multicore 5 Cores Savbit Alloy Ersin Flux, 1.22mm diameter. The main problem was I just couldn't get the bundle of wires hot enough for the flux to flow. I started at about 330 degrees and then eventually went up to 420 or thereabouts at which point the solder finally melted. Trouble was, the rest of the wire going back to the ESC was getting too hot to touch (resulted in my heatshrink, which was tight anyway because it was covering the three wires starting to shrink. I couldn't push it up any further because the wires to the align ESC are pretty short anyway).

Anyway, I persevered and managed to do the solder. Which looks terrible, generally shiny but the odd blob hanging off and also with some brown spots on it, which I think might be burnt rosin (pretty sure ersin is a type of rosin??), probably because I was using too high a temperature? But without the heat I couldn't get the solder to melt.

So ... bottom line ... it's a terrible solder.

Three questions:

1) - Any thoughts on the above, where did I go wrong?
2) - Will there be any issue soldering on (properly) some extension wires to the Align ESC to make it useable (assuming I didn;t toast the electornics in it anyway, but don't think it got THAT hot). At the moment, the wires are too short for me to start over again
3) - If there's anyone in the Harpenden, Welwyn Garden City, Hatfield area who knows how to solder, I'd love to stop by for your help. Even happy to pay the going rate, whatever that is! After this experience, I ain't going anywhere near my 6S 5000mAh lipos to put on my XT60 connectors without help. Bloody bomb waiting to go off! :-)

Thanks for the help.

[alistair.howie]

Here's the damage! Embarassing! Looked so easy on the videos ... heat the joint from underneath, get it hot enough, let the solder flow from above, hold the heat, etc.

[Red3]

hi i use EC5 connectors on my 550e with a cc bec its a nice large connector to get all your wires in and will Handel the current. i think maybe the problem is the xt60 is to small a connector