clinch nailing

[Reed]

Hey folks -
I'm researching building a strip built boat called the dolly varden ( http://www.svensons.com/boat/?p=Utility/DollyVarden ) it referrs to clinch nailing the frames in the hull.

question: is this the same technique that gives Peterborough boats their unique look (the little dots all over the cedar hull)?

who supplies these types of clinch nails?

Thanks for any advice,
Reed in Lakeville, MN

[lewisboats]

Nails are usually a copper alloy. Clinching refers to a method of fastening the nails by bending over or mushrooming the nail after it has penetrated the layers, drawing the layers together.

Steve

[PAR]

It's clench or clinker and is a thin copper nail with a fine point and slender tip. Depending of the application, location and type of wood, the tip is bent back over (forming a "U" shape) either with or across the grain. Under a coat of paint the tips all but disappear. The heads are sunk, on the outside of the planking during the clenching process and usually puttied over.

Most of the marine fastener supply houses carry clench nails, but the size is location and application specific, so you'll need to refer to a set of plans, though there are rules of thumb for sizing and length.

[lewisboats]

See...and that's why I'm not a senior member, just an amature designer/builder

Steve

[gonzo]

Canoes usually had copper tacks called "canoe tacks". They look like a carpet tack. Clench nails are of rectangular section and less pointy.

[Bergalia]

And don't forget that clench nailing requires a 'washer' on the inside of the planking before doubling the shaft back... :rolleyes:

[Rod Tait]

It would appear from the picture that the hull is probably constructed the same way the old cedar/canvass canoes were. The ribs would be steam bent over a form that has metal bands on it for rib placement. When you add the planking, you drive a clench nail through the planking and rib whereby it hits the metal band and bends over. For nails, I like the canoe tacks available at Lee Valley. They are made of a brass alloy and are very sharp and come in different lengths.

[byankee]

There seems to be some confusing information coming your way on this topic. Clench nails do not need "washers" (properly called "roves") under them, and the nails are not "mushroomed" over. That's a description of riveting, not clench nailing. As others have told you, clench nails are bent over and directed back into the planking. The resulting shape is similar to a staple with one long leg projecting through to the outside of the planks (where the head of the nail is).

See http://www.faeringdesigninc.com/index.html for illustrated instructions on both clench nailing and riveting. They also sell nails, rivets and roves.

[Bergalia]

I think you're being a bit pedantic byankee. Traditions in fastening, like the names of fasteners vary from country to country - even from neighbouring parts of the same country. Clinch, clench, roves, washers. What the heck.
Methods may differ - but the end result is the same. :rolleyes:

[chandler]

Regardless of country or language, byankee is correct, clench nails are bent over.rivets are rivets, in boats done manually as opposed to a pop rivet.