Lots of these rigid vangs break, compared to rope vangs
which are more reliable, obviously. As OZ stated booms often
break right at the vang attachment point. This is a weak point
because of the leverage, as CM stated.

Not if installed correctly. I had my Quick Vang boom bracket break loose from
the boom once as we crossed the starting line of a race. The reason for the
failure ..... the nitwit who installed the boom fitting attached it to the thin
walled boom with machine screws and no backing plate. I would be all of 2
threads had been holding that fitting on. I drilled and tapped proper sized
holes in a 5' long piece of 1/2" x 1/2" aluminum bar stock and placed it inside
the boom. Now those machine screws have much more meat to get a grip on and
the 5' length really spreads the load. We've done a couple of auto jibes in
big winds on downwind legs with nothing breaking since then.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"

On 19 Aug 2004 05:55:35 GMT, (SAIL LOCO) wrote:

Lots of these rigid vangs break, compared to rope vangs
which are more reliable, obviously. As OZ stated booms often
break right at the vang attachment point. This is a weak point
because of the leverage, as CM stated.

Not if installed correctly. I had my Quick Vang boom bracket break loose from
the boom once as we crossed the starting line of a race. The reason for the
failure ..... the nitwit who installed the boom fitting attached it to the thin
walled boom with machine screws and no backing plate. I would be all of 2
threads had been holding that fitting on. I drilled and tapped proper sized
holes in a 5' long piece of 1/2" x 1/2" aluminum bar stock and placed it inside
the boom. Now those machine screws have much more meat to get a grip on and
the 5' length really spreads the load. We've done a couple of auto jibes in
big winds on downwind legs with nothing breaking since then.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"


You could have stuck a piece of pipe in your boom. I have heard of
that being done

You could have stuck a piece of pipe in your boom. I have heard of
that being done.

The 1/2" square piece of aluminum bar stock was easier to cut than cast iron.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"

A fine idea.

"SAIL LOCO" wrote ...

I drilled and tapped proper sized
holes in a 5' long piece of 1/2" x 1/2" aluminum bar stock and placed it
inside
the boom. Now those machine screws have much more meat to get a grip on
and
the 5' length really spreads the load. We've done a couple of auto jibes
in
big winds on downwind legs with nothing breaking since then.

A fine idea, my ass!!

Any rigger worth his Salt would have drill thru the boom (2 holes)
Through bolted with the proper size bolt, lock washers and nut in place.

Ole Thom

Thom Stewart wrote:
A fine idea, my ass!!

Any rigger worth his Salt would have drill thru the boom (2 holes)
Through bolted with the proper size bolt, lock washers and nut in place.

With a compression fitting on the inside, of course.

DSK

Any rigger worth his Salt would have drill thru the boom (2 holes)
Through bolted with the proper size bolt, lock washers and nut in place.

LOL.................. That might work if your boom was only 2 feet long or if
you had 6 foot arms.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"

Backing plates are used everywhere on boats--it is a good method and
excellent solution to Loco's problem.

You don't specify how the thru-bolts are drilled horizontally, or
vertically. Most booms have holes drilled horizontally with a bale
attached. That would not work with a rigid vang. You would need
to make a custom wrap-around bracket to thru-bolt horizontally.
You could use a piece of solder shaped around the mast and boom
to transfer the shape to template such a part--Garhauer method.

Machine screws into tapped hole into a backing plate inside the boom
strike me as an excellent method of reinforcement to spread the load
along the axis of the boom.

I've also seen sections of snug fitting tubing sleeved as reinforcement at
places prone to failures like the vang attachment, and sometimes the
gooseneck to increase boom strength. The method is commonly used
to built taller masts in sections. My Ericson mast is the original, was
constructed in three pieces and has not failed in over 30 years of use.
This would be the best solution.

Thru-bolting adds extra holes and can weaken both sides of the boom,
particularly if over tightened, by crushing or dimpling the shape of the
boom,
thus creating a weak spot. This is more common on smaller and lighter
booms, and vang related failure occur where? Right at the thru-bolts!

Reinforcement is common for boom repairs. Loco's method is a good
one to spread the load and secure the vang to the boom. If your boat
has a reputation for failing at a certain place like the vang attachment
at the boom, consider reinforcing it before the boom brakes.

"Thom Stewart" wrote

A fine idea, my ass!!

Any rigger worth his Salt would have drill thru the boom (2 holes)
Through bolted with the proper size bolt, lock washers and nut in place.

Ole Thom

Ah Balls Bart,

Count up the number of holes drilled and tapped with the backing stock
and connection of the vang and then compare it to a full bale.

Ole Thom

Count up the number of holes drilled and tapped with the backing stock
and connection of the vang and then compare it to a full bale.

The 4 - 3/16" socket head screws that hold the Quick Vang bracket to the boom
are of no consequence when compared to the 3/8" or larger holes that would have
to be drilled for a bail. Plus a bail wouldn't work with a Quick Vang bracket.
And with a 1/2" piece of aluminum bar stock installed inside the boom it's
like da holes ain't even there.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"