[J22-Fleet 1] Vang and sheet attachment to boom

[Michael Bowers]

Do not drill more holes.  This is a critical spot on the boom and more
holes are begging for a stress point/critical failure.

One windy day on the Charles river we lost about 5 Tech booms in the course
of 1 hour.  The common thread was that they had all recently been repaired
by drilling out new vang bale holes in the boom.  If only someone had done
a stress/strain analysis of the boom prior to sinking all those holes.
It's not like they couldn't have run across the street to MIT and
asked anyone in the Mech E department. ;)

The link that Peter posted has some very good suggestions.  I think the
best one is making sure you have a bolt that does not have threads
contacting the aluminum.  I'd reuse the same holes, but address whatever
issue it is that caused them to elongate in the first place.

Mike

On Mon, May 2, 2016 at 9:00 AM, Peter McHenry via J22 <j22 at lists.wyc.org>
wrote:

> Check out SA form:
> j22 vang bail holes, boom anarchy poll. - Fix It Anarchy
> <http://forums.sailinganarchy.com/index.php?showtopic=156965>
>
> j22 vang bail holes, boom anarchy poll. - Fix It Anarchy
> j22 vang bail holes, boom anarchy poll. - posted in Fix It Anarchy: Im
> helping a friend replace the outhaul line...
> <http://forums.sailinganarchy.com/index.php?showtopic=156965>
>
>
>
>
> On Saturday, April 30, 2016 10:27 PM, dallas--- via J22 <j22 at lists.wyc.org>
> wrote:
>
>
> The vang and main sheet bail attachment points on our boom have become
> elongated.
>
> Is there a more sophisticated repair than simply drilling new holes
> nearby?
>
> Sent via mobile
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