Drilling holes in the boom

[Achillesheel]

...is one of the jobs for the weekend, as i want to fit a couple of fairleads for reefing lines etc.

But will someone confirm that four holes for self tapping screws will not compromise the strength of the boom, please!

(11' aluminium boom)

 

[Phoenix of Hamble]

Yep.... I drilled similar holes in my mast, and it didn't fall down!

 

[michael_w]

Just remember the Duralac and avoid the tension wall (bottom of boom/front of mast).

 

[boatmike]

No it wont but I would use monel rivets not self tapping screws and coat with Zinc Chromate paste before riveting.

 

[Achillesheel]

What is a monel rivet? Is this what I call a pop rivet?

 

[Phoenix of Hamble]

yes.... but Monel is a particular form of metal.... most cheap pop rivets are aluminium....

 

[kengill]

do not have the holes near the fixing point for the kicker.

PS anyone want a short boom?

 

[Sailfree]

Whenever I see a bent boom /mast they have always buckled and therefore failure is in compression.

Q1 Are you sure its not best to drill holes on the tension face (providing not too many!!)

Q2 Which is the tension face as with wind forces and potential pumping of the sails at times do you not get an amount of stress reversal.

 

[michael_w]

If you've got a half decent kicker arrangement to control mainsheet shape, say 16:1 your boom will bend. I've had several fail (Merlin-Rocket, International 14, Contessa 33, IOR half ton. Each time the seat of the failure has been holes drilled to take the kicker fitting.

On the 14 we ended up using a 4" diameter spinnaker pole section, loose footed with webbing straps to take the kicker and mainsheet. Employed webbing straps when the solid kicker tore chunks out of the Contessa's boom. It pulled out mid-ocean.

The tension wall of your mast will always be the front, unless you've got your rigging incorectly set up and the mast is inverting.