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qm
11-15-2006, 09:55 PM
Can anyone figure out or say when they were first used in wooden boats???? I'm trying to get the age of a boat I have, Some signs tell me it was built in the 1920s, but maybe it was the 1880s(natural knee/galvanized keel bolts/deep forefoot/fancy hook scarfs in covering boards/skeg/etc. QM Bob

StevenBauer
11-15-2006, 10:04 PM
Brass or bronze?

Jay Greer
11-15-2006, 10:36 PM
Aside from the fact that brass screws were used for fresh water craft prior to the discovery that electrolytic action would soon destroy the fastenings, I have no benchmark to give you an appropriot date for the use of brass screws. Just judging from my own experience with brass fastenings, I would avoid, at all costs, there use in boats that intended for use in salt water.
JG

Todd Bradshaw
11-16-2006, 12:11 AM
"natural knee/galvanized keel bolts/deep forefoot/fancy hook scarfs in covering boards/skeg/etc."

That ain't no guideboat....

Graeme Forrest
11-16-2006, 01:31 AM
Just a thought. I recall reading somewhere, possibly the Bray/Pineiro book, that Herreshoff Manufacturing Co. used brass screws for planking fastenings for some years, later changing to Tobin Bronze(which despite its name is also brass, outside the US the same alloy is usually known as Naval Brass). Herreshoff boats seem to have lasted ok:D. Due to the construction system used by Herreshoff's they would have had to use screws or similar to fasten the planking instead of fastening properly with rivits:D (ducking now)
Graeme

nedL
11-16-2006, 06:37 AM
I suspect brass was in much more common usage prior to WWII than most might think, this goes for both fresh water and salt water boats. - I'm basing this comment on materials list I've seen for boats built in the pre-war years where brass screws are specifically listed.

Thorne
11-16-2006, 09:01 AM
Read somewhere (maybe Chapelle's _American Small Sailing Craft_?) that brass screws replaced iron clenchnails as the marine fastener of choice, allowing more rapid construction of boats -- but can't remember the timeframe, possibly late 1800's?

QM - as usual, a good description of the boat in question would be a big help, as would any photos.

Jay Greer
11-16-2006, 09:31 AM
Herreshoff constantly used the term Tobin Bronze in when specifying certain alloys for various machined components of his designs. It is more commonly known as "Naval Brass" in England and now in the US brass and bronze markets. Its main use in boats is for its strength.
The alloy consists primarily of copper and tin with a small amount of zinc as well. Often lead is added in order to make it more machinable. True brass is an alloy of copper and zinc. It is the degradation of zinc that causes brass to not fare well when in a condition that allows electrolitic action to occur. It didn't take the early builders long to become aware of this characteristic as their fastenings let go at an alarming rate.
JG

pcford
11-16-2006, 12:21 PM
Not an answer to the original poster's question but:

From my experience with runabouts and powerboats, it appears that brass fasteners were used 'til roughly the mid 30s. I believe that is when the alloy Everdur (sil. bronze) was developed.

Before that time, brass fasteners were used. Also, builders then were much less fastidious than we are today regarding mixing metals. Often the backbone fasteners would be steel, for example.

I just finished putting a deck on a vintage hydroplane. (Ventnor, 1948) It was brass fastened. Deck fasteners were #6 brass straight slots. Total nightmare. Don't try this at home folks.