Bend in wooden mast

[AuntyRinum]

How much bend is it safe to put in a forty foot hollow spruce mast?
Lots? None?
Any thoughts would be welcomed.

 

[Peterduck]

The spruce can take a surprising amount of bend, but the limiting factor is going to be the glue holding everything together. How much do you feel you want to stress those glued surfaces? What kind of glue was used, and how long ago was it fresh? I would recommend keeping a straight mast as straight as you can. If you want a bent mast to satisfy a theory of aerodynamics, then have a bent mast built. Boats that have to retire from a race with a damaged stick don't even get a look at the silverware.
Peter.

 

[AuntyRinum]

Thanks for that. It pretty much confirms what I was thinking.
I have a Hillyard 12 Tonner and have just restepped the mast and am adjusting the rigging.

 

[vande9389]

Don't bend it. It was not designed with that in mind, and I am not sure how much faster or higher pointing you would get a 12 tonner. I also have a 12 tonner and the advice I had from the Hillyard yard the other day regarding standing rigging was not to have it too tight. It does not need to be tight at all. If you are going to bend the mast via the backstay (assumption on my part) you will be putting extra unneccesary pressure on the deck.

If you have a compression post under the tabernackle, again be careful, because any extra tension on that standing rigging will be tranmitted to the keelson. I am not sure what the result will be but she wasn't designed for that.

Regards

 

[oldfrank]

Acceptable degrees of mast bend bend will depend on a number of factors - certainly including age of glue (waterbased glue will just give up the unequal struggle) but even if it's epoxy glue there will be other considerations such as wall thickness. The only real reason you might want a mast to bend on a sailing boat is to fit the sail - a mainsail with a large amount of luff round will require more of a bent mast. Similarly if you want to loose some of the power then bend the mast to free the leech and dump some wind. There's no magic to wooden masts - they need to respond just like a metal mast and fit the mainsail. As I recall the only reason that wooden dinghy spars fell from favour was that humidity made them less predictable that their tin alternatives.

On a Hillyard you almost ceratinly don't want your mast to bend (unlike a Star with a wooden mast). If your mainsail has a lot of luff round then either have it altered or get a new sail.
Hope this helps. Old Frank

 

[AuntyRinum]

Thanks