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copper buss bar

B

bwestfall

Well Known Member
I purchased the copper buss bar stock from Van's which is .063" thick x .5" wide with the notion of making buss bar connections between the battery lug and starter solenoid on the firewall. The lugs are 5/16" in diameter which leaves about 3/32" on either side left in the buss bar. Do typical edge distances apply here? Is this acceptable? I would think it OK simply because there should be no movement or vibration between the battery lug and starter solenoid at all. It's a fairly important connection though and one not intended to fail mechanically.

If I wanted to purchase wider material where does one usually find it?

Is this acceptable... thoughts?

buss_bar_s.jpg
 
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As it is non-structural I see no problem with it. Consider that the edge distance on the typical wire terminal is less than or equal to what you have.

Don
 
Actually for those things I'll beat a piece of copper pipe flat and since I'm usually bending them I file/scotchbrite for last stage.
 
Buss Bar

An exposed copper bar behind the panel is an accepted norm. Not so much for forward of the firewall. Personally I want all my firewall forward wiring to be standard wire and protected with boots at both ends. Just too much potential for some piece of metal to short out the entire system forward of the firewall. Behind the panel, for those who want to go to the extreme, a rubber "curtain" can be installed to protect the circuit breakers and switches.
 
Can't remember what the actual name for the stuff is but the rubberized liquid tape works well for insulating copper buss bar. You just paint the stuff on after the copper is installed. The liquid rubber that you can instulate wrenches with also works well.
 
I covered as much of mine as I could with shrink tubing, not shrunk but held in place with zip ties.
 
Bah. I've seen many busted ring terminals (some under boots). Bars can be insulated and I don't recall ever seeing one broken.
 
Copper bus bar

Hi Ben:

I purchased mine at Metal Mart. I used large shrink rap tube to cover the exposed area. Worked out well.

Terry
 
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If there is any relative motion between the battery and contactor due to vibration, then welding cable should be used instead of a Bus Bar.
 
update work in progress

There should be no relative motion between any of these connections as they are all secured to the firewall relatively close together.

Here is the work in progress using the buss bar stock from Van's. I coated the pieces with shrink tubing except for the ends. I do plan to go back and put those white rubber boots over the bolts.

buss_bar_2.jpg


buss_bar_3.jpg


I do plan to replace those nylok bolts with a nut and lock washer on the ANL fuse. Those are the bolts that came w/the ANL holder and I have not gone and gotten new ones.
 
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copper bar connection

How thick does the copper bar connection between solenoids have to be?
I flattened a copper pipe into a bar but it didn't seem thick enough at 0.055 inches. So I made two and used them both. Now the thickness of the copper bar is 0.11. Will that work okay? Is there any reason why it should be solid bar rather than 4 thin bars snugged together?
 
If you are using Vans copper strips double them up to be the equivalent of 2 gauge wire.

Not essential, but it keeps the same amount of copper along the entire path if starter currents are involved.
 
Speaking of starter currents, a long time ago I used a surplus 500A shunt and a 50mv analog gauge to "measure" my starter current. I was trying to figure out what size wire I needed. The pointer on the meter was oscillating with the compression strokes, but the eyeball "average" was roughly 400 Amps. (high compression O-290-D2, Sky-Tec high torque starter, and B&C 100-1 25AH battery ) I now own a Fluke 87-V true RMS meter and should try the test in a more rigorous manner sometime.
 
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Something to consider - most of the solenoids are mounted with an top mounted bracket which then bends down the back of the unit. These solenoids will vibrate in an oscillating manner.
 
humptybump said:
Something to consider - most of the solenoids are mounted with an top mounted bracket which then bends down the back of the unit. These solenoids will vibrate in an oscillating manner.
Click to expand...

Most of the solenoids I have seen sold for aircraft use have a bent piece of metal formed and welded to the cylindrical body of the part.

SkyTec and Lamar aircraft solenoids are similar -

07-01875.jpg


And even the industrial versions -

11-03161.jpg


Pics from the Spruce catalog.
 
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