Battery, starter, alternator cables

I would like to replace my original vans cables. Could I get opinions on gauge size on them with welding cables, just not sure what size would be needed. I know the vans is a 2 gauge.

Battery to contactor?
Atl to firewall?
Starter to contactor?

Would a 6gauge welding cable a good size to handle the power needed. I have a 60amp alt

2 gauge is fine for the path from battery to starter, and from engine block (ground) back to the battery. With a firewall mounted battery, you might be ok with 4 gauge.

6 gauge is more than adequate for that size alternator; 8 might be adequate, depending on length.

The gauge measurement doesn't change between a/c cable & welding cable.

The advantage of welding cable is that it's typically a lot more flexible; the (potential) downside is that the insulation is thicker, so it may affect the ability to get it through existing bulkhead passthroughs if they are already near full.

Charlie

2 penneys.

Our two cents would be just like above. I have a set of 25 foot jumper cables made up with a Cessna plug on one end and a set of car type spring clamps on the other end. Those are made with #4 welding cable, but. We would not use anything less than #2 for Bat. cables and #6 for Alt. "B" leads in the aircraft and in both cases we use only Aircraft grade or Mill. spec. Tefzeel wire with good wire lugs crimped very nicely. Just our two cents. Yours, R.E.A. III #80888

Thanks for the tips!!

My -7A has 4g from firewall mounted battery to master. Master to starter contactor is brass bar stock. Starter contactor to starter is 4g. PlanePower 60A to ANL is 8g. Same from ANL to bus block inside.

Ground is 4g from firewall FoT block to engine. If you are installing the battery further aft of the firewall, 2g may be needed.

No issues with spinning the Skytech starter with this setup. Typical bus load with everything on is 20A.