Copper grounding strap

[ed c.]

Need input from forum. Price of copper is at a 4 1/2 year low. I have 3 " strap and was thinking of bending it to 1 1/2" because of the thickness.

[Tony Meola]

Ed

Are you thinking it is two thin.

Bending it would be a pain in the you know what. Especially for the run you need. I used .022" thickness.

http://www.gacopper.com/022-CopperStrap.html

[ed c.]

I just got more info from a book titled Your Boat's Electrical System by Miller & Maloney. The min. thickness should be 1/32" and 1/2" wide. They also say you can use 3/4" or 1" copper tubing because it is easy to handle,convenient to connect to and has adequate conductivity.

[Joseph Fikentscher]

As in Plumbing Pipe?

[IRGuy]

My boat has factory installed strips of thin copper about 1" wide running along two stringers from the engine room forward to under the V berth. They have studs protruding from them for bonding wires to connect to. Some of the studs are corroded and no longer useful and the bonding wires are no longer connected to them.

Does anyone have a suggestion as to how to attach more studs to the strips? I am afraid to try to pull the strips away from the stringers for fear of breaking them.

[Charlie J]

frank if you can drill a hole thru the strap, connect the wire with a bolt

[Tony Meola]

I used the 1 inch wide. The strap as shown is for lightning ground.

1/32 is .031 which they also offer.

You can also use 8 guage wire. A little easier to use that copper pipe.

IR

Just use 8 guage wire to jump from a good connection to the next one. I would suggest running a whole new set up.

[CaptPatrick]

Might also be a good time to review: http://bertram31.com/proj/tips/bonding.htm

[Navatech]

Might also be a good time to review: http://bertram31.com/proj/tips/bonding.htm

Question about the bonding... The page says "all metal objects that come into contact with raw water should be bonded"... Does that include above water line objects (e.g. through hulls for the AC cooling water discharge)?!...

Also, the link to the Newmar isolator manual is dead... It results in a 404 error... I guess Newmar changed the file's location... The correct URL is http://www.newmarpower.com/Manuals/Manual-GI-30&50.pdf. ..

[CaptPatrick]

ALL metal objects that come into contact with raw water should be bonded, especially AC discharge through hull fittings...

Thanks for the heads up on the Newmar link.

[Preston Burrows]

Frank,

I found the easiest solution for attaching more bonding wires to the copper bonding strap was to epoxy flat head bronze bolts to the bonding strap after pre-drilling the appropriate sized hole in the strap, assuming you do not have the perforated type bonding strap,in which case I used bronze washers to ensure good metal to metal connections.............pry the strap away from its mounting surface, ready your epoxy, dap some on the bolt head and bonding strap...... then slip the bolt behind and through the strap hole..... then tap the strap back and flush to its mounting surface......occasionally some weight was needed to keep all flush until the epoxy set, anything nearby worked for that from an anchor to the beer bottle I had just finished drinking.....

The epoxy would also help re-attach the strap flush to its mounting surface if necessary and an emery board, or sanding cloth, used to clean away any excess epoxy would make short work of ensuring there was a good metal to metal connection for the bonding wire afterwards.

Happy 2015 to you all.

[IRGuy]

Thanks guys for the info! Once again the Bertram brotherhood comes through!

Preston..
Are you saying that you are epoxying the top of the head of the bolt to the underlying stringer, or is there epoxy bonding the underside of the bolt head to the back of the copper strip? And if so, are you sure you have good electrical contact? In either case are you somehow scrubbing away the corrosion and paint that is most likely on the back side of the copper strip?

And something to add to the items that should be bonded...
I have spoken with a marine electrician who advised me to bond the outriggers as well as all wetted parts. His reasoning was that the bonding system would bleed away the static charges that would accumulate at the tips of the outriggers, which increase the potential for lightning strikes. These are not installed as conductors to ground for lightning strikes, but to minimize the chance for lightning to strike.

I would appreciate any comments from those here who are more familiar than I am with lightning strikes and their prevention.

[Tony Meola]

Frank

Not sure that bonding the outriggers to the system would bleed off static electricity. The base of the pole has a rubber coating which would break the connection.

[Preston Burrows]

Frank,

Yes to all your queries of my method.

(The electrical connection is assured by way of the front or face ['non stringer side'] of the Bonding strap, which I emery board clean and check for continuity, the bronze bolt simply acts as a stud upon which I mount the Bonding wire by way of a terminal eye and a bronze washer, fastened down with a bronze nut on the 'face' of the Bonding strap.)

Interesting what your electrician states about 'bonding' your outriggers against 'positive leaders' so as to help prevent lightning strikes.

[IRGuy]

Preston...

Thanks for the explanation.. sometimes the obvious is not so obvious for me!

I am trying to locate the electrician.. I understand after a divorce he has dropped out of sight. It seems like some guys do that.

Frank