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Collecting ground terminals

Flying Canuck

Flying Canuck

Well Known Member
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I've got most of my instrument/avionics out of the panel at the moment, chasing down an issue where I was losing my secondary avionics stack for some unknown reason. This is a good time to think about grounds.

I have maybe 2 dozen airframe grounds each ending in a ring terminal that I want to bond together. I am thinking about sliding them all onto a long machine screw, holding them in with a lock washer/nut or double nut. That screw would be secured through a bracket to prevent excessive vibration. Is this a good idea? I tried the terminal block approach - it's awkward and requires jumpers to join the block's connectors together. The machine screw seems much easier.

Thoughts?
 
This, makes a very good ground connection and is easy to wire....
ground block.JPG
Push-on....
Far better than ring connections, by design.
 
gasman said:
This, makes a very good ground connection and is easy to wire....
View attachment 49419
Push-on....
Far better than ring connections, by design.
Click to expand...

"We" (sorry) have seen a number of these FASTON style connections fail with high resistance in the circuit. The workaround is to apply dielectric grease to the spades -- forms a gas-tight seal and prevents corrosion.
 
bjdecker said:
"We" (sorry) have seen a number of these FASTON style connections fail with high resistance in the circuit. The workaround is to apply dielectric grease to the spades -- forms a gas-tight seal and prevents corrosion.
Click to expand...

By design, they provide a superior connection when compared to an eye and screw.

I use this on every electric connection......
deox3.JPG
 
I bought some copper strip and bolted 5 x 1" bolts through it with some thick glassfibre on the back. The GF was drilled so the bolts were flush. Another strip was bolted to the back and to the structure to insulate the whole stack. This gave enough space to have around 6 terminals on each post with a thick (14G) wire from the end to a central ground. I have 3 of these strips and plenty of spare space. Audio system is very quiet.
 
Standard wiring practice limits a single threaded fastener to a maximum of four ring tongue terminals. One caninstall more but it gets ugly fast and, in the long run, ends in disappointment.

The "forest of tabs" approach works well, but as others have noted, push-on terminals do have their challenges with longevity, even with some inox-style of compound applied to them. The loss of "spring tension" applied by the terminal is what I have most often observed as the failure mode.

Over the years I've had excellent success with MS27212 terminal strips. If one uses a strip of copper to join the terminals (water pipe actually isn't bad for this, IF properly protected from corrosion) or one can buy the ridiculously-priced purpose-designed buss bar material for these terminal strips. A strip of 10 terminals provides 40 ground locations.
 
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