How to connect components on firewall together

[bill@fusion4.net]

Well, I went off plans, and that has led to more changes then I expected.

This picture shows my firewall passthrough of my main battery cable, the starter soliniod, and the fuseable links for the alternator and backup alternator.

My problem is how do I connect them. They are too close together for even 2 terminals back to back. The Firewall passthough is a 3/8" bolt. I had tried using 1/2" copper busbar stock from B&C, but drilling a 3/8" hole for the bolt does not leave enough material on the sides.

Should I get some 5/8" copper busbar stock or 3/4"? or does anyone have a different solution/idea.

[Mike S]

Get some 1/2" dia copper pipe.

Cut to the length you need, and then flatten it down.

Drill holes as needed.

You can even use some large heat shrink to cover the center portion.

For other buss bars like circuit breakers, I use a 1" copper coupling, cut off a ring a little wider than 1/4". Cut it open, flatten and there is my buss bar.

[Gonzo24]

Bill, You nailed it! Wise words indeed and I laughed when I read your post.

"Well, I went off plans, and that has led to more changes then I expected..."

That should be a T shirt logo for sure when it comes to these planes.

As I continue to plod along through this never ending -7 build I am constantly reminded how many times I took "just a little departure" from the plans and.... 18 steps later... a particular custom task at hand is almost finished. (james cowl, home grown plenum, air intakes, back up electrical, ram air, etc, etc, etc...)

I 2nd Mike's copper pipe super buss bar idea. It works like a charm.

Education via experimentation... thanks for the laugh and build on brother!

[bill@fusion4.net]

That is just the idea I needed. Off to HD Aviation on my way home. Don't have to order or wait for anything

[Daniel S.]

Dude. I don't know why I didn't notice this the other day... Turn your Starter solenoid upside-down so you can pull some G's (in turbulance of course) and not inadvertently grind the gears from the starter engaging.

[gasman]

I would agree about the copper coupling....... except use a 2" coupling. It is a lot thicker.

[Captain Avgas]

Originally Posted by Daniel S.

Turn your Starter solenoid upside-down

Or, in other words.....turn the starter solenoid up the right way. Unless of course the photo that was posted is upside down.

When it comes to the electrical architecture and associated firewall fittings, some serious time for planning in advance of drilling holes should be allowed. The old adage "haste makes waste" applies to this part of the build in particular.

[gasman]

Originally Posted by Captain Avgas

Or, in other words.....turn the starter solenoid up the right way. Unless of course the photo that was posted is upside down.

When it comes to the electrical architecture and associated firewall fittings, some serious time for planning in advance of drilling holes should be allowed. The old adage "haste makes waste" applies to this part of the build in particular.

Maybe, The fuseable links are also mounted upside down.

[bill@fusion4.net]

Thanks for the critique as well. I knew the fuseable links were in upside down, I had just thrown them on the firewall after I had already 'stopped' work for the night and was just trying to get an idea of where I was going to be working the next day. All of the components shown just have screws pushed through the firewall, but no nuts on them at all. I had not even opened the firewall forward instructions yet. But thanks for all the input. Much better to have 100's of eyes catching things then to grind starter gears and loose alternators because things are not install correct.