<br /><br />Technically, its not electrolysis; its a galvanic thing, tho we commonly call it electrolysis and everyone knows what you mean when using that term. Electrons in metals are displaced due to the interaction between the electrical potential of their atomic structure. The greater the difference in the electrical potential between dissimilar items, the greater the interaction.<br /><br />In the case of your boat, your prop, shaft, thru hulls, etc are all exposed to water and somewhere else in that same water there is likely to be something with a different electrical potential. Dissolved salts/metals in the water allow electrical current to flow between those items. Zincs corrosion potential is such that it is likely to go first before other alloys that are common in marine use. As DR mentioned, they are sacrificial
intended to be eaten away and replaced. Doesnt always happen. Sometimes the zincs sit on a boat, untouched for years. Other times they are gone beyond usefulness within months.<br /><br />They are definitely one of those things are better to have and not need then to need and not have.<br /><br />When galvanic corrosion occurs, the electrons migrate from the anode (+) to the cathode (-). Can you figure out what direction the electrical current is flowing with a sacrificial "anode" zinc? Likewise, wanna take a guess as to which lead plates in a battery are eaten up when it fails?
.<br /><br />Sivart, take a look at this table of nobility - you don't need no stinking anodes if you build your boat out of gold! <br /><br /> http://www.mcnallyinstitute.com/CDweb/g-html/g001.htm <br /><br />Tip #2: Don't mix different types of stainless fasteners.<br /><br />Aldo
Originally posted by 18rabbit:<br /> Im not going to mess with zincs anymore. Theyre big and expensive. Mark posted some good stuff on making molds in another thread. I think with a little aluminum powder I can mold some zinc-looking epoxy pieces that will fit right in there but wont erode away like zinc. Should look the same but will save me some big bucks in the long run.
You Guys are Just Kidding........................Right............
I am..... I'm really lazy and probably will only put 1 really thick coat on it untill it drips off. This way all the edges will be sealed and I won't have to worry about that nasty salt water interfering with a shiny new anode.
until your engine our out drive rot away from galvanic erosion, then how much would you save? i put new anodes on my outdrive and after only 20 hrs in the water (saltwater)they are worn considerably, if they were made out of epoxy, the outdrive would have holes in it by now. there is a reason and the engineers @ mercruiser are alot smarter than me, if it didn't need something, I doubt they would have spent the money on R&D to make the parts in the first placeOriginally posted by 18rabbit:<br /> Im not going to mess with zincs anymore. Theyre big and expensive. Mark posted some good stuff on making molds in another thread. I think with a little aluminum powder I can mold some zinc-looking epoxy pieces that will fit right in there but wont erode away like zinc. Should look the same but will save me some big bucks in the long run.
you would be defeating the purpose entirly, might as well just take them off and save weight, your boat will gradually weigh less as you use it, because your engine and outdrive metal will get thinner and thinner until it has holes in it.
Jimmy, I think your onto something.... this would make my boat lighter and more streamlined (less metal on the lower unit = less metal to cause drag in the water) and therefore faster!!!!!<br />I can't wait untill the lower unit is paper thin... should be the best performance I will get out of the boat.<br /><br /><br />yes I'm kidding
<br /><br />Yes, Jimmy...we're just kidding. 
