Better ground with star washers?

pgerhardt said:
Yea, overthinking is SOP for me! :D On almost every operation I have already completely done it in my head before I pick up a wrench. The actual operation is usually easier than I imagined it.

Being a wholistic thinker has pluses and minuses. On the one hand, when coding, I usually have the whole program in my head before I start. On the other hand, on the restorations I often wish I could just relax, jump in, and just do it. But usually I am not comfortable unless I have the whole project laid out in my head first.
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As a one time coder I solved the over thinking problem by moving to management - never had to think again....

More seriously, when working on computer hardware from several different manufacturers I noted that they all used star washers and unpainted surfaces for ground connections which were very important for older mainframes.

I use the same approach, but as my cars do not run in climate controlled computer rooms, I protect the connections with generous helpings of grease. My favourite grease for this is Vaseline, but I use what ever is at hand.
 
If you use star washers for ground contact then use zinc, cad or tin plated steel ones. Stainless steel has a passive invisible oxide layer on the surface and makes a lousy electrical contact. Ask any electroplater about the surface properties of SS.
 
With skinny mechanics' wire, bent back at the end, Chief always pulled extra ground wires through the looms, especially on the head lights & tail lights.
Bill W.
 
pgerhardt was right on the money with the star washers. Not only do they provide the best ground they keep things from moving around like the infamous point block.
HAPPY MOTORING, DUTIE
 
harleytoprock said:
I like using star lock washers under the terminal. It makes a good connection and the termlnal doesn't spin when you tighten the nut or screw.
Di-electric grease is a grease that does not conduct electricity. If you want a good connection a regular light grease is better. Di-electric grease is used on multi-terminal connectors on sensors or modules of modern cars, so no current leaks between terminals. "Di-electric" means it's not a good conductor.
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I don't know the properties of dielectric grease but I do know "The Phone Company" (NY Telephone) issued it for outdoor connections utilizing 22 gauge wire. Those owning British cars in the 1950's through 1970's enjoying LUCAS ELECTRIC systems also used dielectric grease successfully on our electrical connections.
 
chuckwp said:
OK on outide of connectins but, dieletric grease is NON conductive so, keep it from getting between connections.
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Yes, in theory you are correct. As it was explained to me, the pressure applied to the joined pieces caused by the fastener displaces the grease enough allowing the contact of the electrical.

If someone is still worried, they can apply carbon conductive grease instead of dielectric, but we have been assembling with Permatex brand dielectric (-from NAPA) for years and have not experienced conductivity issues. We just remove the paint from the jointed areas and apply the grease as a rust prevention step.
 
Terry said:
I think the best way to get a good grounding spot on a daily driver would be put a spot of brazing or lead solder around the ground connection bolt hole. What we're talking about is a very conductive, non rusting contact point. And I looked around in my bolt drawer for a 3/8 brass bolt. ( I did not solder or braze my frame) I used a auxillary ground cable. And unless I'm dreaming, it made a difference. Think about what makes engine to frame ground in a mod A. Dirty, rusty steel bolts that in many cases are backed up with contacts drenched in grease. They might have been fine when new, but that was a long time ago. I haven't done it, but has someone ever checked with an ohmmeter, the electrical resistance just going through the frame rails to the crossbars and unpainted frame? It probably varies all over the lot from frame to frame and rivet joint to rivet joint. Just a thought!
Terry
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A dedicated high quality ground point will absolutely make a tremendous difference. Thing is, every electrical connection is a potential failure point. What that means is it will slowly degrade over time until it fails. Most people don't pay any attention to this unless or until the engine won't start.

Interestingly enough, an ohmeter or resistance measurement is practically useless for this kind of thing, because in a low voltage high current system the amount of ohms resistance required to cause major problems is almost too low to measure accurately. So automobile engineers about 1915 devised the "voltage drop test", engine starters, charging systems, headlights and accessories, grounds and connections in particular are tested while they energized under load. Excessive resistance in a circuit can be inferred by the amount of voltage drop. The accepted figure is still 0.2 volts for the ground system. Zero would be best, but there will always be some. Even just a tiny bit of extra resistance - maybe a tenth of an ohm - will cut alternator capacity by about 30%.

Interestingly maybe too much, while brass or copper studs, washers &c at the frame might seem to be a good idea at a major ground point, studies have shown dissimilar metal corrosion and fretting occurs. Good old plain steel washers and studs and ordinary hardware work the best over time. The "Star Washers" are most definitely a work around for the OEM, they work for their intended purpose to cut through the paint and primer down to bare metal and get the car out the door, and not outright fail within a reasonable time period. Somebody told me they aren't even used any longer by automakers.
 
For automotive wiring, a separate ground wire to each appliance is the most reliable. Not cheap and not always easy.
Star washers are extremely reliable if made from heat treated beryllium copper. Space ships and ICBM's use them.
Examples taken from WW2 radio equipment that saw duty in the tropics, still appear as new today.
Readily available and relatively cheap.
 
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