In a message dated 4/20/2010 9:25:16 PM Pacific Daylight Time, shipchief@aol.com writes:

I'm thinking an aluminum plate of 6061 could be cut, drilled, milled, then the wear faces "Nikasil" equivalent electroplated.

Is that fairly straightforward if P Ported?

Chief,

Yes, that is a possible method. Do something for me. Look up the coefficient of linear expansion for aluminum. Then look up the coefficient of linear expansion for chrome (or Nickasil). You will find that the aluminum is about 10^-5 units per degree F. Chrome is about 10^-6 or 7 units per degree F. Every time the engine heats up the aluminum is trying to expand itself right past the coating. It work fairly well in a bore, and less well on a flat surface. That is why Mazda paid so much money to do detonation gun coatings on their all aluminum Le Mans engine. I checked on these coatings and they are just silly expensive. The raw coating was about 1000 dollars per FACE and then you need to lap it. In a car used for road racing Nickasil might hold up, but think about putting that car on a track with a 200 mile long straight-away. That is what our aircraft use is like. I am not one of the dumb car engines can take it guys, but there are differences and some of those differences make it tough to just use coatings. Not impossible, but expensive. Now if you could make an intermediate housing that was one pound heaver than aluminum but had none of the problems, while still being around 12-15 pounds lighter than the stocker, doesn't it sound like a good idea?

Bill Jepson

 

Bill,

Well said - now what are you going to charge us - I want mates rates.

George ( down under)