Rigid Boom Vang to Boom Connection

[corkhead]

I have an Garhauer Rigid Boom Vang which I want to install. The mast end is easy, I am using the existing bracket to connect the boom vang. The boom connection requires a stainless plate with three holes on each side to attach to the boom.
My questions:
1. is it better to pop rivet using SS rivets (1/4" hole on bracket)
2. Is it better to drill and tap, the boom wall is so thinn it worries me
3. Since access to the interior of the boom is difficult is there another solution
4. Have a professional do it

This is for an Ericson 35-III

Thanks for any suggestions.

 

[Mike Thomas]

Julian

I installed a Gauhauer rigid vang last year on my E-29. I drilled and tapped with 1/4-20, Truss head, SS, machine screws. I have to believe that the sticks (boom and mast) on an E-35 will be at least as heavy as on the 29. So you shouldn’t have a problem.

The screws I used are like the ones on this page (see truss head) (http://www.boltdepot.com/machine-screws.aspx#Phillips-Flat-Head). I didn’t buy them from this vendor but this is what you want.

I found that holding everything together with tape, marking the boom and mast, removing the boom and drilling/tapping on the hard was easiest.

Remember that the sticks are heat treated so use a new bit, keep it cool and tap slow with some lubrication. A new bit and tap is worth it to do the job right. You don’t want to break off a tap.

Before final assembly I put a thin sheet of rubber (gasket) between the boom/mast and the plate. I also wrapped the threads on the screw heavily with Teflon tape (plumbers tape). I figured that doing it this way I was preventing some electrolysis by isolating dis-similar metals. Everything has worked out great.

You will love the G-H rigid vang. No more topping lift and I think that I get much better performance in light air.

Mike T
E-29

 

[ted_reshetiloff]

I am installing mine by welding in the part Kenyon sells on this page:

http://www.rigrite.com/Spars/Kenyon_Spars/3756-boom.html

scroll down until Heavy-duty Weld-in Vang Tab: K-11700L:

I am actually making my own from 1/2 thick aluminum. Less electrolosis trouble by not using any stainless. If you are using the external fitting I would drill and tap as Mike suggests but use a fine thread like 1/4 X 32 if you can. The wall tickness of the boom is not much and if you use a fine thread you will have a much tighter fit that will be less likely to vibrate loose. Use a gasket as Mike suggests and use some silicone on the screw threads. Pop rivits would not be the best solution here.

 

[corkhead]

vang attachment

Thanks! Two good options.
Julian

 

[Dave G]

Boom Vang Connection

Not to be contrary, but I have a Garhaur rigid vang on my E-29. I made a connection fitting from 1/4" aluminum plate bent and formed to match the boom with a tab welded on to accept the end of the vang. I attached it to the boom with four 1/4" pop rivits on each side, it's be working great for 3 years with no problems. I figured if the rivits started to work loose I would drill them out and replace them. I love the set up, getting rid of the topping lift is great!

Dave Green
Bellingham, WA

 

[Art Mullinax]

Second the pop rivets.

When working with thin metals, a pop rivet tends to hold better. At 32 threads/in, 1 full thread is equal to 0.032". If the boom is 1/16" thick, you have only 2 threads. Not much for a piece of equipment that is going to be subjected to a lot of force. If you have to use threaded fasteners, try a size 10-32 rather than 1/4-32.

 

[stbdtack]

If you drill and tap for machine screws use locktite on the threads. Not only does it keep the screws in place but it seals out moisture to prevent corrosion. The blue stuff is removable but I would opt for the red. Red is supposed to be more permanent but a little well placed heat will break it down if you ever need to remove it. Another good thread protector is Tef-Gel. It is one of the best moisture barriers available, also is a great anti-seize. Its not a locking compound though. Garhauer and Shaefer use it on all their threads.

http://www.spursmarine.com/tefgel5.htm