Is it ok to use aluminum for a busbar, or power distribution block?

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MileHighDart

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Made up this power distribution block the other day. But thought I'd check with the experts before I start wiring this into the car. Ok to use aluminum for this ?
This would be bolted to the inner fender near the firewall, mounted with nylon bolts and washers, and I will be making a cover for it to avoid any contact when working under the hood.
Was planning on using this to feed battery power to everything I have on relays. Fuel pump, ign, and a couple others that I'm about to ad. Battery stud on my starter relay is starting to look like an octopus, so thought I'd add a distribution point to run all this stuff.

IMG_20200325_132907337.jpg
 
NO I would not do this under any conditions. Review some of the issues with aluminum wiring "back then." with oxidation and corrosion issues. Plus here you are using this in a very unfriendly environment. That is my opinion, it is mine alone, and you will not change it.
 
67Dart273 said:
NO I would not do this under any conditions. Review some of the issues with aluminum wiring "back then." with oxidation and corrosion issues. Plus here you are using this in a very unfriendly environment. That is my opinion, it is mine alone, and you will not change it.
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And I wouldn't trust those plastic standoffs either.
A little over current draw and those could melt causing a huge short.
 
67Dart273 said:
NO I would not do this under any conditions. Review some of the issues with aluminum wiring "back then." with oxidation and corrosion issues. Plus here you are using this in a very unfriendly environment. That is my opinion, it is mine alone, and you will not change it.
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No, it's not yours alone. It's mine too. No way in hell would I use aluminum for the exact reasons Del recommends. Moisture will for sure cause corrosion with the aluminum and that will lead to some really nasty consequences......like grounding out and maybe even a fire.
 
RustyRatRod said:
No, it's not yours alone. It's mine too. No way in hell would I use aluminum for the exact reasons Del recommends. Moisture will for sure cause corrosion with the aluminum and that will lead to some really nasty consequences......like grounding out and maybe even a fire.
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I agree there are issues with aluminium corrosion at connections. But can't they be mitigated with pastes. Isn't that what they do for farms/ homes/outbuildings with aluminum wiring? Not trying to be a contrarian. I think I'd use copper myself, and I'd be concerned with safety with the standoffs, like somebody else suggested, or inadvertant contact with a wrench or foreign object causing a short or even some sparking. Isn't there that kind of stuff readily available aftermarket, that is purpose built for this kind of an application, which would be safer to use?
 
Aluminum oxide is dielectric (doesnt conduct electricity well). The problem is that corrosion keeps increasing the resistance of the connection until it heats up and melts or burns. Some pastes can help, but are a bandaid and not a cure. At best whatever is drawing current will slowly get less and less until faults and gremlins occur.

Brass, nickel plated steel or copper.. Those are safer bets. Raw copper is also OK, but will look ugly in short order. Stainless is iffy, but mostly OK. You'll also want to enclose as much of the conducter as possible to prevent unintentional shorts.

Nice fabrication though!
 
MileHighDart said:
Made up this power distribution block the other day. But thought I'd check with the experts before I start wiring this into the car. Ok to use aluminum for this ?
This would be bolted to the inner fender near the firewall, mounted with nylon bolts and washers, and I will be making a cover for it to avoid any contact when working under the hood.
Was planning on using this to feed battery power to everything I have on relays. Fuel pump, ign, and a couple others that I'm about to ad. Battery stud on my starter relay is starting to look like an octopus, so thought I'd add a distribution point to run all this stuff.

View attachment 1715499946
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Aviation grade bus bar material. https://www.aircraftspruce.com/catalog/mepages/busbar.php
 
Really? They have used aluminum bussing that carries hundreds of amps and thousands of volts in the electrical industry for decades, which I used to install, but can't be trusted to handle a few amps at 12 volts. Believe me that little piece of aluminum will out last all of us.
 
I haven't looked for some time, but I think my ex-cop 02 intrepid has some kind of oem busbar terminal thingy in the trunk. So maybe you can buy one of those from ma mopar.
 
moparmarks said:
Really? They have used aluminum bussing that carries hundreds of amps and thousands of volts in the electrical industry for decades, which I used to install, but can't be trusted to handle a few amps at 12 volts. Believe me that little piece of aluminum will out last all of us.
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Significant difference between a system sized with proper engineering and specifically developed conductors using engineered connectors/bonding versus tossing together some (very well shaped and finished) scrap sheet metal with nuts and bolts. The alloys of aluminum used in electrical industry are also fairly specific to electrical industry and not common in sheet stock. These alloys are developed specifically to avoid fatigue and galvanic corrosion, and even then they tend to be clad with materials that play nice with connectors. Aluminum in electrical utilities is a result of cost and weight consideration only, not because it's easier to deal with or superior in performance.

Cars are also subject to a much more variable environment with exposure to greater temperature swings, poor upkeep, road salt and grime, etc. Fixed electrical operations just don't compare.

Could an aluminum bus bar work in theory? Yes.

But why risk inconvenience or worse when doing it with more durable and commonly accepted materials is just as easy and probably cheaper?
 
Ok, I'll save the bolts and connectors, and junk the rest.

Looks like there's plenty of options available online for busbars and accessory fuse boxes, and actually pretty cheap.
 
Yes very correct but were also talking about 12 volts, not 15KV. You really think he will have problems with that piece of scrap? Yes there are better materials but I don't think he building a rocket here. I just think he is fine with he has made but everyone says to toss it and start over.
And as a side note if you have ever pulled 500 MCM then you would know that aluminum is much easier to deal with than copper, but not superior.
 
Check out Summit, Jegs, and Amazon. You will be supprised, at what comes up for fuse/bussbars. Jegs has 10% off all Jegs brand stuff right now.
I use Jegs for my aux power center, and all in my latest project.
Dave
 
6D1DD825-E0BB-4E54-A311-4A99941D063C.jpeg Eaton 14-Terminal Ground Bar Kit-GBK1420CS - The Home Depot

OP, I’ve used a readily available “Ground/Neutral Bar” from HomeCheapo. Use the large lug for your feed and the smaller set screws for your circuits, add another large lug at the other side for your starter wire if needed. This setup eliminates your yellow crimp connectors too. Enclose this in a plastic hobby or electrical box for insulation purposes....
 
moparmarks said:
Yes very correct but were also talking about 12 volts, not 15KV. You really think he will have problems with that piece of scrap? Yes there are better materials but I don't think he building a rocket here. I just think he is fine with he has made but everyone says to toss it and start over.
And as a side note if you have ever pulled 500 MCM then you would know that aluminum is much easier to deal with than copper, but not superior.
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True, but once that aluminum oxidizes it turns into a little heater element at the point of connection. The aluminum plate is just fine to carry a lot more than any car would need for just about any circuit, but how things are attached to it is where problems come from.

I like the suggestions to use some sort of fuse box though - didn't occur to me but I built a couple like for those for similar purposes and it works great. I was dumb though and paralleled two fuses one one circuit (I think for the alternator charge line, even) thinking it would be fine. Nothing but trouble..

I hate that he is tossing it because it really is a very good looking peice, especially compared to the cobbled together junk so many guys hack together. Just hate to see it also be a point of pain when/if the connections fail or burn through.

As far as pulling wire, never done it... I'm the geek who sits at a computer rather than doing the real work ;) but I've done enough back breaking labor to appreciate dealing with lighter assemblies! Like I said, in utility work there's enough benefits to offset potential drawbacks and risks, completely different world.
 
Well I'm a dummy myself. I thought he was using it as a ground buss. I need to stay off of here when I have a headache.
 
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