Bronze vs. Monel

[Pelican]

For your basic things (nuts, bolts, screws) do y'all feel monel is worth the extra expense? For things like engine mount lag screws would you use one of these or stainless?

I remember reading once what the difference is but am now in a state of perpetual senior moments and it totally escapes me. Seems like monel had a lot of nickle in it but I'm not sure.

[paladin]

If you can offord it....go with the Monel....

[Pelican]

Uh, I'm going to show my total supidity, what is the CDA website? redface.gif

[PugetSound]

Dave,
you have it backwards..... Monel is 70/30 with the emphasis on nickel (70%). Monel is slightly heavier than steel and is generally very corrosion resistant. "Monel 400" is the alloy commonly used in the marine environment. Never ever combine monel with stainless steel as the resulting corrosion/errosion of the stainless steel is truly something you have to see to believe. Monel (NiCu)is often used in conjunction with a nickel alloy called Kmonel (NiCuAl) which has a yield strength in the neighborhood of 80 ksi (as compared with Monel's yield strength of 26 ksi or mild steel's of 36 ksi).

Basically, monel is worth the extra expense but be careful of it's galvanic impact on less noble alloys.

[NormMessinger]

Pelican, please note: It's your money we are spending, that's why it is so easy to recommend monel.

--Norm

[pwilling]

Dav, could you spell out the net address for the Copper Development Ass'n again -- it doesn't come across. Tks.

[Ed Harrow]

Well, time for a question. Monel is more noble than bronze. That makes it even more noble than iron; yet one is told to never use bronze with iron, but monel. I've talked with a PhD materials person (two actually) and they don't understand the rational.

So what says you???

[Dick M.]

Ed:

You might contact Roger Winniarski at Bristol Bronze, Tiverton, RI. He is very knowledgeable and very willing to talk about metals and wooden boats. Good luck.

Dick

[Noah]

I know that I say this every time, but boy do I wish that I had bought a 26ft sloop that I looked at last summer. It was built in 1953, cold molded, and every piece of metal on the boat was monel. Even the stove. Plus it was owned by a wooden boat surveyor, who didn't have the money to go sailing anymore. Asking price was only $5000. What a fool I was. It was in absolutly perfect condition, with not an ounce of rot that I could find anywhere, and I took 4 hours looking at the boat.

Ahhh well. My point was, has anyone ever seen a monel stove before? Pretty cool I guess. It was special order and cost a pretty penny in 1953...

Noah

[Nicholas Carey]

Another useful resource is that collection of metalheads known as the Metal Boat Society. You can find them at http://www.metalboatsociety.com/

[Pelican]

Dave: Thanks for the link. This takes you right to the 70/30 and 90/10 section: copper (http://marine.copper.org/NACE00627/intro.html#90-10)

[Ed Harrow]

Dick, thanks for the tip...