The International Cessna^® 170 Association

So I'm putting together new battery cables and have a question. My IA recommended today that I heat up the cable end with a torch and solder the battery cable to the lug after I crimp it. He said it's not required but that's how he does it. What do you guys do?

BTW...It was hard tracking down some 2 gauge terminals with 1/4'' studs. 4 auto parts stores in my town didn't stock them. Had to find them online.

I put a little dielectric grease in the terminals before I crimped them and then a piece of heat shrink tubing over that.
Seems to work quite well.

I refrain from soldering terminals as it makes the wire rigid at the end of the solder joint....which can cause cracked wires under vibration (at least they did on my old Harley). Crimped terminals don't seem to carry this affliction.

But that's just me.

delete

Thanks for confirming what I was thinking. My IA is pretty old school, but usually is right on the money with his advice. I think I will go with you guys on this one though.

Thanks again, Mike

I wouldn't solder them but I also would pick another battle rather than this one with the IA if he's bent on soldering.

I do a double swage, heat shrink it, and call it good.

Spray or brush the battery terminals and cable ends and inside the battery box with CorrosionX or ACF-50 after installation and at each annual. You will never have any corrosion if you do this.

If your IA reads a little document known as AC 43.13-1B - Acceptable Methods, Techniques, and Practices - Aircraft Inspection and Repair 43.13 (b) ..... he'll find (under section 11-103) the statement: .... "Ensure that only aircraft manufacturer approved devices, such as solderless type terminals, terminal blocks, connectors, disconnect splices, permanent splices, and feed-through bushings are used for cable junctions."

This is because soldered joints will embrittle at the solder and vibration can break the cable. Generally, crimped connectors are preferred in aircraft wiring.

Additionally, do not use welding-cable or common hardware-store cable or automotive cable. Use the correct aircraft grade cables and wires in which individual strands of wire are tin-plated...to reduce corrosion. Such wire, in conjunction with appropriate "tinned" connectors and terminals will not readily corrode.

gahorn wrote:If your IA reads a little document known as AC 43.13-1B - Acceptable Methods, Techniques, and Practices - Aircraft Inspection and Repair 43.13 (b) ..... he'll find (under section 11-103) the statement: .... "Ensure that only aircraft manufacturer approved devices, such as solderless type terminals, terminal blocks, connectors, disconnect splices, permanent splices, and feed-through bushings are used for cable junctions."

This is because soldered joints will embrittle at the solder and vibration can break the cable. Generally, crimped connectors are preferred in aircraft wiring.

Additionally, do not use welding-cable or common hardware-store cable or automotive cable. Use the correct aircraft grade cables and wires in which individual strands of wire are tin-plated...to reduce corrosion. Such wire, in conjunction with appropriate "tinned" connectors and terminals will not readily corrode.

All those references are great, but written long before the envirosplice and heat shrink was invented
http://www.edmo.com/index.php?module=pr ... d_id=18887

tin the wire both sides, slide into the splice crimp, touch with very hot soldering gun, allow to cool, slide the cover over and heat until the wrap is tight. no excess solder sticking out, no flux to cause corrosion and never comes apart.

The stock battery cables that were on my plane have some sort of vinyl tubing surrounding them (see picture). I'm pretty sure it's not shrink wrap. What is this for and is it necessary to go back on the new cables I am making?

Thanks for your thoughts.

Mike

That was an anti-chafe cover and is not necessary with modern cables. The older cables (MIL-5086A) had fiber/cloth cover over pvc insulation which would absorb oil, soften, and was easily chafed. Modern cable spec is MIL-W-22759/16 and no longer uses pvc, but instead uses "tefzel" (extruded ethelene) and is more durable. You can place additional cover over it, but not required.

Got the cables done. I bought the tool pictured below to crimp the 2 gauge battery wire. I didn't like it at all and ended up borrowing another type of crimper that worked much better. Here is the finished product. I used some dow dielectic grease before I crimped. I really like how it all turned out....just mad I bought the wrong tool.

I used an ordinary tubing-flaring tool which worked perfectly (with the added pressure of a vise or hyd/press.)