Which metal is better for terminal blocks?

i'd use copper. Copper have the best conductivity of the 3 and fairly ridgid.

Copper if you make sure the cables fit as perfectly as possible on the rail, so there won't get air in between that makes the copper oxidize and reduce the contact.

I will use copper rails too for my power distribution, but if you go that way, you have to know why fuseblocks/batteryclamps/amp-terminals... aren't made of unprotected copper and prevent the reasons why it isn't...

The thing that does worry me about the copper is the fact that it can oxidize if not protected properly. This distribution block/rail will be in the engine compartment, copper does offer the best conductivity but in this case would it be better to use aluminum or stainless steel.

Shod said:

The thing that does worry me about the copper is the fact that it can oxidize if not protected properly. This distribution block/rail will be in the engine compartment, copper does offer the best conductivity but in this case it would be better to use aluminum or stainless steel.

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Fixed:laugh: Although I would choose stainless.

Tinned copper should work.

Shod said:

The thing that does worry me about the copper is the fact that it can oxidize if not protected properly. This distribution block/rail will be in the engine compartment, copper does offer the best conductivity but in this case would it be better to use aluminum or stainless steel.

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As mentioned above, I think the only place that would be a concern is in the actual connection point. Which after connected, the area would be air and water tight not allowing any chance of oxidation in that critical area.

All other exposed part would only oxidize to a certain degree and then would be protected by the actually oxidation layer (this is why copper water pipes don't corrode into nothing over time and why copper is used in the exterior hull paint to protect ships).

If an area that has oxidized need to be used later on, then just fine sand it clean.

ALTHOUGH!, this only applies to water and humidity protection. Battery acid or any other chemical in the area might be a different story.

Deox is our friend when making connections; and I assure you copper will stand up better than aluminum ever thought of doing.

The piece you want to fabricate looks great and useful too! I'd use copper, brass, or bronze for the actual block. I'd also use electrically conductive contact paste on the screw connections. If you want to minimize the the copper oxidizing as well as keeping it looking good, have the part nickel-plated. It is not expensive if you shop around and nickel is durable. You could make a stainless steel mounting strap as shown in the image with the copper part screwed to it.

I would not use stainless or aluminum though as the base material. Stainless has fairly high resistance and aluminum oxidizes immediately upon exposing new metal. Copper oxides are still decent electrical conductors but aluminun oxides aren't. It is too bad because base aluminum itself is terrific electrically.