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Yep, Carbon is conductive and will cause electrolysis to eat the alloy
rivets very fast. Use stainless instead. If you have very salty water like
Robert its going to be a nightmare to have dissimilar metals contacting each
other, and or carbon. As you see from the lists below Graphite and
Aluminium are about as bad a combination as you can get. Our NYC Skiffs mast parts (in fact, all our carbon parts) are covered with an outer and inner layer of glass as an insulator for this reason. If you are using Bram's new CB block attachment system, pay particular attention to the long thin bolts and their nuts that serve to hold the CB blocks in place. Make sure the metals are not dissimilar or as close as possible in galvanic potential. You can also protect dissimilar metals from galvanic corrosion by 1.. Sealing - by sealing to insure that faying surfaces are water-tight especially on fayed surfaces. 2.. Resistance - by painting or coating all surfaces to increase the resistance of the electrical circuit. Regards Greg. For your information only, Listed below is the latest galvanic table from MIL-STD-889, for any combination of dissimilar metals, the metal with the lower number will act as an anode and will corrode preferentially. Active (Anodic) 1.. Magnesium 2.. Mg alloy AZ-31B 3.. Mg alloy HK-31A 4.. Zinc (hot-dip, die cast, or plated) 5.. Beryllium (hot pressed) 6.. Al 7072 clad on 7075 7.. Al 2014-T3 8.. Al 1160-H14 9.. Al 7079-T6 10.. Cadmium (plated) 11.. Uranium 12.. Al 218 (die cast) 13.. Al 5052-0 14.. Al 5052-H12 15.. Al 5456-0, H353 16.. Al 5052-H32 17.. Al 1100-0 18.. Al 3003-H25 19.. Al 6061-T6 20.. Al A360 (die cast) 21.. Al 7075-T6 22.. Al 6061-0 23.. Indium 24.. Al 2014-0 25.. Al 2024-T4 26.. Al 5052-H16 27.. Tin (plated) 28.. Stainless steel 430 (active) 29.. Lead 30.. Steel 1010 31.. Iron (cast) 32.. Stainless steel 410 (active) 33.. Copper (plated, cast, or wrought) 34.. Nickel (plated) 35.. Chromium (Plated) 36.. Tantalum 37.. AM350 (active) 38.. Stainless steel 310 (active) 39.. Stainless steel 301 (active) 40.. Stainless steel 304 (active) 41.. Stainless steel 430 (active) 42.. Stainless steel 410 (active) 43.. Stainless steel 17-7PH (active) 44.. Tungsten 45.. Niobium (columbium) 1% Zr 46.. Brass, Yellow, 268 47.. Uranium 8% Mo 48.. Brass, Naval, 464 49.. Yellow Brass 50.. Muntz Metal 280 51.. Brass (plated) 52.. Nickel-silver (18% Ni) 53.. Stainless steel 316L (active) 54.. Bronze 220 55.. Copper 110 56.. Red Brass 57.. Stainless steel 347 (active) 58.. Molybdenum, Commercial pure 59.. Copper-nickel 715 60.. Admiralty brass 61.. Stainless steel 202 (active) 62.. Bronze, Phosphor 534 (B-1) 63.. Monel 400 64.. Stainless steel 201 (active) 65.. Carpenter 20 (active) 66.. Stainless steel 321 (active) 67.. Stainless steel 316 (active) 68.. Stainless steel 309 (active) 69.. Stainless steel 17-7PH (passive) 70.. Silicone Bronze 655 71.. Stainless steel 304 (passive) 72.. Stainless steel 301 (passive) 73.. Stainless steel 321 (passive) 74.. Stainless steel 201 (passive) 75.. Stainless steel 286 (passive) 76.. Stainless steel 316L (passive) 77.. AM355 (active) 78.. Stainless steel 202 (passive) 79.. Carpenter 20 (passive) 80.. AM355 (passive) 81.. A286 (passive) 82.. Titanium 5A1, 2.5 Sn 83.. Titanium 13V, 11Cr, 3Al (annealed) 84.. Titanium 6Al, 4V (solution treated and aged) 85.. Titanium 6Al, 4V (anneal) 86.. Titanium 8Mn 87.. Titanium 13V, 11Cr 3Al (solution heat treated and aged) 88.. Titanium 75A 89.. AM350 (passive) 90.. Silver 91.. Gold 92.. Graphite 93..
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