Centreboards and towing

[Jonathan Stuart]

I used to occasionally lower the centreboard on to the trailer keel rollers after recovering to take the board's weight off the board's blocks and ropes etc. I wish this had become a habit! Despite its line being secured in the cam, my board dropped mid-launch at Sail Caledonia yesterday and I found the board's forward block had broken during the drive up - see attached photo. Interesting (but annoying) that it wasn't the sheeve or bearing that broke but the metal. Fortunately I had a spare that fitted so we're sailing again, but I won't leave the board raised when towing anymore. Given the weight of the BRe's board there must be some significant  forces acting on the board's blocks and line if it's bouncing around when driving and clearly that will cause something eventually to fail.

Jonathan

[Rob Johnstone]

Hi Jonathan,
Is the metal at the fracture crystalised? If so the failure may be caused by metal fatigue over a long timr, rather than just in the length of your journey north. But lowering the centre board onto the trailer rollers appears to be a sensible practice to adopt!

[mainecoast]

Great heads up, Jonathan.

I have lowered while the boat is in lay up, but a good point on taking the strain while transiting, as well.

Only other option might be to place some foam up on either side of the centerboard to keep the rattle down...but lowering seems the best bet.

Glad you had a spare to put to use.

Thanks for the share.

Pete
s/v Corvus
BC23 Hull 37

[Matthew P]

Strain on the centreboard pivot and up-haul rope on my BR20 while towing has worried me since I bought the boat. So I have always fitted a cam-buckle (used for securing canoes to roof racks) tie-down right around the hull to support the rear of the centreboard. This seems to be effective although I am careful not to over-tighten and squeeze the hull.  I don't know if this would work on other boats.

Matthew
BR20 Gladys 

[Jonathan Stuart]

Now back from Sail Caledonia and am relieved to report that the temporary block for the centre board worked fine all week. I suspect that Rob's suggestion is correct and this was caused by long term metal fatigue - that seems more likely because the load to cause a "sudden" failure in this block would surely be significant and the metal does seem quite "grainy", so I wonder if that's the crystalisation Rob mentioned. If this was caused by metal fatigue then that makes it even more important to support the centre board whenever towing.