Re: Rudder Failure - builder error!

Posted by Jeremy on
URL: http://uk-hbbr-forum.61.s1.nabble.com/Rudder-Failure-builder-error-tp3338284p3338323.html

Sorry to hear of your accident.  Marine ply is already pretty much as strong as you're going to get using timber in this thickness, but you could make a new rudder blade from 6mm ply with a composite skin on either side to increase the strength and thickness up to 9mm to fit your stock.  It would take a fair bit of work, using epoxy and glass cloth, best laid with the weave diagonal to the major axis of the rudder for one layer, with the next layer laid so that the weave goes along the major axis, then alternating this pattern until you have around 1.5mm thickness laid up on each side.  Best to shape the 6mm ply core first, so that there is little need to shape the epoxy glass afterwards.

Alternatively, you may be able to take the epoxy glued stock apart.  Epoxy softens at around 100 to 120 deg C and then becomes fairly easy to unbond.  The problem is going to be getting enough heat through the stock to the epoxy.  I'd suggest trying something like a steam chest, leaving the stock in there for long enough to get the heat right into the epoxy, then trying to gently prise it apart.  Depending on the area of the bond you may find that this is the best way forward, as if it works it would be less work than making a composite sheathed rudder, I think.

Jeremy