DIY copper bus bar

Golden_HVAC wrote:
Hi,

I had plenty of 1/2" diameter ACR tubing, that comes on a roll, and is filled with nitrogen at the factory, to keep it clean inside. The soft copper is easy to bend, and will not crack when you try to flatten it. I used my 6" bench vice, it worked well!

What I did was flatten out about 3" of tubing, then fold back about 1/2 of that length. Drill a 3/8" hole in the flat section, and the remaining 1/2" or so, (that was not flat) I put the 000 size wire in it, and then clamped that in the vice, so it never failed (well since 1997 - it might fail someday). . .

If you are looking for a 'ground' bussbar, then flatten 1/2" tubing, and have the end open to accept the wire going to the battery. This can be any size, say #4 wire, then clamp that in the vice, it will hold forever! You can drill 1/4" holes where needed. Put in a #10 screw about 1" long and a nut right next to the copper. You can then add about 5 wires to that screw, and put on another nut, to hold all the solderless connectors to that bolt. Use multiple bolts, with 3-5 wires per bolt, or bolt a large amperage wire directly to the copper buss.

For a 'hot' bussbar, I would recommend a fuse assembly. Your local auto parts store should sell a fuse holder with 6, 10, or 12 fuses of 5 to 30 amps capacity for each fuse. Normally they also have a large terminal for the +12 battery wire.

You don't want more than about 12 fuses, as normally they have 20 amp fuses, and you would want only about 100 amps load on each fuse box, due to voltage loss over the wire between the fuse holder and battery.

Plumbing water pipe is all copper, but normally fairly stiff. The ACR tubing or tubing sold on a roll, it will have less zinc in it, and more pure copper, so it will be softer. You can buy 50' roll of soft copper at Home Depot, where they probably also sell it by the foot. 2' will make 8 each 3" long battery terminals, or the bussbar (say 6" long) and several battery terminals.

Good luck!

Fred.

Regular plumbing copper which is sold in 10ft "sticks" is known as "hard" copper. It is not the ideal choice for flattening since it is so hard and will work harden as you smash it.

The real choice is called "refrigeration" tubing (aka "soft copper"), it is much softer to flatten and is sold in rolls. It will also work harden but since it starts out very soft and pliable the hardening is no issue.

I have used refrigeration tubing to make my own copper crimp and solder terminals for 2 ga and even 1/0 wire. Find the size of tubing which just slides over the wire. Crimp then solder.. Flatten the open end and drill hole in the flat spot.. Cheap and effective.

Tried that for my 250A DC stick welder.. Worked great for 2 ga welding wires then did the same for my Inverter and batteries for my TT.. Works like a champ.