Bent chain plates

[weheritage]

Is there a safe way to bend a bronze chain plate back into position without removing it. The starboard side took a hit during one of the hurricanes last year and the forward chain plate is about 15 to 20 degrees bent inboard. The chain plates are on the inside of the hull covered by inside planking. Constructive help appreciated

[ssor]

Procede slowly, bronze has a tendency to work harden. This is a small deformation, maybe, depending on the length of the chainplate. Bending it back into position may require rebedding.

[TimothyB]

The safest way is to remove the chainplate, anneal it, and bend it. (otherwise, the bronze will weaken, which is probably something you don't want to deal with in a chainplate)

Here is a Q&A I found on annealing bronze:

Q: I need to bend a thick piece of bronze, but it is too stiff. Any ideas?

A: This will be easier to do if the bronze piece is annealed first. While steel is annealed
by heating to red and being allowed to cool slowly, metals which crystalize in the
"Face-centered Cubic" system- which includes the copper alloys as well as gold and
silver- will reharden if they are treated this way. The crystals, given time, will form a
more organized structure, without the molecular "vacancies" which make the metal
malleable. In fact, one can take advantage of this tendency to "heat-harden" non-ferrous
metals, holding sterling silver, for instance, at 280 degrees C (536 F) for 2 1/2 hours.

To soften metals of this type, they should be brought to a medium red color, then
quenched in water to cool quickly. I would be careful not to overheat it though-
some bronzes will suddenly go from solid to falling-apart when hot. See Tim
McCreight's excellent handbook "The Complete Metalsmith" c. 1991 Davis Publications,
Worcester Mass ISBN 0-87192-240-1 for more details on annealing and hardening, as
well as other aspects of the hand metalworker's craft.

[ 07-01-2005, 10:54 AM: Message edited by: TimothyB ]