Boom Hanger for Timber Boom

[kimtrang]

I'm trying to source a boom hanger for a mahogany boom, so I can install a boom brake. The boom is about 4 inches wide. As it is a older boat it is very long and seems very heavy. It has a round profile with a grooved flat section on top. I'm worried about weakening the spar if I drill a hole through the side.

Any suggestions?

[GordMay]

“Practical Sailor” wrote about boom gallows designs for the modern cruiser ➥ https://www.practical-sailor.com/new...s-10484-1.html

[kimtrang]

Thanks Gord, but this is like an attachment point on the boom for a boom vang. Kind of like a pad eye, but with the ability to withstand a very heavy load without weakening the structural integrity of the boom. It would be about 5'6" from the mast.
Sorry for the confusing post.

[GordMay]

Boom Bail? ➥ Marine Boom / Mast Bails
➥ https://www.westmarine.com/boom-bails

[DLLuce]

My wooden yawl had a roller-reefing boom, round with a flat spot next to the track, made out of solid spruce, rather than mahogany. When a preventer was needed, I had a heavy canvas strap with two bails, one at each end, that passed around the boom and held the vang. The boom was so heavy the vang was seldom needed; in winds less than 10 knots, I often had to use the topping lift to shape the sail.

I replaced the round boom with a hollow rectangular one, using the scantlings in Skene's Elements of Yacht Design. The bail for the new boom is made of 1/2" silicon bronze, welded to pads on both sides, and bolted twice through it. The vang is attached to a 3/8" padeye on deck bolted through a beam and two backing blocks in the deck next to the mast. The new boom is stiffer and lighter than the round one.

[UNCIVILIZED]

Simplest is to make a spectra strop, & hang your hardware from it. And you can even put a few of them onto the boom with some space in between them, so as to spread the load over more of the boom, & connect them at a common point, where you'll then hang your hardware.

The same can also be done using webbing. And it's easy enough to fabricate a long aluminum plate with slots for each webbing loop, & a hole for the shackle or the brake. Thus spreading the load out over as much of the boom as you like.

Drilling for a bolt needn't weaken things, done properly. Simply make the hole large enough so that you can glue in an oversized G-10 or aluminum compresion tube. With or without doubler plates overtop of said tube. And the "plates" can be clear glass, metal, G-10, wood, or some other material. Also, if you add doubler plates it's wise to bevel their edges so as to avoid creating stress risers.

Which, if point loading the boom is a concern, then doubler plates are the best way to go, as a boom brake can generate a lot of load. Or rather it's a good way to go if you don't distribute it's loads over a portion of the boom's length via multiple strops or webbing straps.

[Dougtiff]

Do not drill a hole thru the boom for a preventer, it's wood not metal, have a sail loft make a strap say 10" wide,tapering to 4" wide at the bottom and 24" long, with grommets in the end's, the strap can be made out of say 9 oz. sail cloth, the advantage using a strap is it can be moved for or aft on the boom, which obviously not doable with a fixed bail, i have had mine for more years than i can remember, when i change boats, i keep the strap along with the block and tackle.