SailNet Community - View Single Post - Drilling into mast & boom
View Single Post
post #6 of Old 01-27-2013
Senior Member
Join Date: Feb 2011
Location: San Francisco Bay area
Posts: 3,073
Thanks: 9
Thanked 83 Times in 82 Posts
Rep Power: 7
Re: Drilling into mast & boom

Originally Posted by Jimmy E View Post
Picked up new traveller and solid vang.
I'm am very comfortable with installing new traveller- filling old holes, drilling new, backer plates and so on.
I need to find a resource or two regarding the instal of my solid boom vang. I'm uneasy drilling into the mast without a solid plan. Any advice on procedure or steps would be appreciated. I wouldn't take issue with even the most rudimentary advice.
I have been told that I should install the vang with a rate of 80% compressed , with the boom at a right angle to the mast....ideas?

I installed a Garhauer solid vang a couple of years ago, and it has stood up well to abuse in "the slot". Here is the procedure I used :

There are two goals you are trying to meet :

1) That, with the main sheet in hard, it never ends up fully compressed, as this could snap the boom.

2) Fully extended, you get plenty of lift on the boom so you can see nicely for motoring and reefing is easy (easy to tighten the reefing outhaul)

Set the vang to about 90% compression. Hoist the main, and sheet the main in as hard as you can. It should be flat as a blade. Then offer the vang up and see how it fits. You are aiming for less than 45% angle, vang to boom, so that it will be operating at more like 45% under normal use. In my case, this meant mounting the vang to the mast as low as possible.

Mount the vang to the mast first, then repeat the step above with sheeting the main in hard with the vang at 90% compression. Mark the boom, then you can drill and mount with the main dropped again.

What you can do to leave yourself some adjustment, is only drill the middle pair of the sets of 6 holes. Then if you don't like the fit, you can move back and forth (or up and down) by one set.

I used these 1/4" rivets from McMasterCarr :


Stainless steel, domed, high strength, 2750lb sheer strength EACH. That means you could lift the boat by my vang.

You need a serious riveter for these things.

Here's the thing in use :

Finally, I've found it tremendously useful to have the vang sheet brought back to the cockpit. Now it's possible to adjust it easily, we adjust it a lot.

Bristol 31.1, San Francisco Bay

Last edited by MarkSF; 01-27-2013 at 09:43 PM.
MarkSF is offline  
Quote Share with Facebook
For the best viewing experience please update your browser to Google Chrome