Vang/ Gooseneck

[jrflorida]

Has anyone used the SailsETC vang/gooseneck (available from GBMY for about $27)? It seems to be an alternative to more expensive models for $60 or more. I have used the same SailsETC vang type on my IOM for about 3 years and it seems to do the job, that is, hold the boom down.

[Greg Vasileff]

I also have been using this gooseneck /vang on my IOMs and it works great. I now use it on my Star 45 and I do pretty good with it. I now build my own ball bearing goosenecks with compression vangs for my Solings and will most likely do this on my EC12. I would though say that the SAILetc unit should work great with the EC12 and it might end up on mine. But just remember that it is not a compression vang. I'm not sure myself which is working better.

greg V
http://ghmyc.org/

[Rick West]

John,
The $60 vang is not a compression vang but the one you will see the most at the regattas. A stout compression vang is needed for the EC12 but not produced. I have not even seen one from an individual craftsman.

The reason it would be nice to have one is that solid vang pulls down on the boom at close haul when you are trying to get close to center line. This is called Sheet Vanging, as it pulls down on the boom causing the twist in the main to decrease or even oppose. Some do not want this but want to have a center position. This is were the Post fairlead comes in and that is another story.

The solid vang does one important thing though and that is in light air it will place the main in a posture to receive light movements of air. A non-solid vang will not do this and the weight the boom removes the shape.

The cheapest vang is a turnbuckle and wire between the mast base and the boom. It is a disaster in light air and is the last to pick up the air if at all.

The SailETC vang will serve as a solid vang. The question is will it survive when you have need of a B rig. I personally have not heard.

BTW, your input to the building site is appreciated. You will probably not see that stuff on the site till next winter. I am on the water in real boats or sailing RC till October. I will get to it......Rick

[jrflorida]

Rick, thanks for the info, it helps my thought process. The SailsETC vang would have to be modified to fully support the boom. The end at the boom is only a hook in a hole, and there is slop at the mast so it will turn easily. The whole thing is made rather loose so there is no binding, but it would loose support of the boom. The end of my short, 14" IOM boom moves up and down 1/2". Maybe that vang is not the answer. John

[s vernon]

I am trying to understand the mechanics of this thread.

I believe when someone refers to a compression vang they mean a vang that holds the boom down, supports the boom in light air and also yields to sheet tension when the boom is near centerline. It seems to me that there are two ways to accomplish this. 1. As pictured on page 109 of Optimizing - with a spring - on Bob Wells's boat. 2. Using a thin rod (2-56 if it is long enough) which will support the boom but which can be easily (but not permanently) bent when the sail is sheeted in near the centerline. Also a compression vang has to have zero (or near zero) play or else the support feature is lost.

I believe that there is no support feature on the SailsETC vang.

Near the centerline the sheet is pullng down on the boom. The solid vang is not yielding and is actually putting an upward force on the boom at that point. A compression vang would yield and allow the boom end to drop reducing twist. That is my understanding of the term "sheet vanging."

Speaking of homemade vangs. I admire Earl Boebert's version as pictured on Chad's discussion group - New Owners section - Gooseneck for Victoria.

http://www.rcsailing.net/forum1/topic.asp?TOPIC_ID=425

His design has a great feature that fires the imagination. He uses a fishing swivel as part of the vang. That particular swivel might not be up to the rigors of an EC12, but how about one of those Bass Pro 75 lb swivels with the loops slightly squeezed and inserted into an aluminum rod on one end and a threaded coupler on the other. Probably an aluminum tube over the coupler to increase the dia where the forward loop is inserted. Then a couple of well placed pins to help out the epoxy. Probably have to pull the loop with a string into the aluminum tube to eliminate play. And a long 2-56 rod to make it "compression". Just a thought. Sounds like a lot of work.

PS. Thank you Gregg for the image. I have seen the US1M construction guide. It just never ocurred to me until I saw Earl's vang that that sort of design could be applied to a vang.

Scott

[Greg Vasileff]

Scott,

As you may know, Earl's thinking here with the BB swivel is not really new thinking. This is a method that has been used in turnbuckles for a while now.

As far as these turnbuckles go, I know many in the EC12 class like using the simple clevis pins. This link from the US1M construction guide shows the use of this same swivel arrangement. I figure that most here have reviewed this construction guide at some point, but if you have not, then maybe this would interest you.
Follow this link http://www.amya.org/us1mpt3.pdf and go to the last page, 17.
The entire construction guide can be found here http://www.amya.org/us1mcons.html

Here is a photo of the turnbuckle arrangement.
http://members.tripod.com/~ghmyc_1m/Tur ... r_Greg.jpg

greg V
http://ghmyc.org/

[Philip Whitley]

Hi all,

I have just finished building a rebuilt boat, with the benifit of my lathe and Milling machine. In New zealand we use a stubby to hold the mast and the main boom. We leave the main boom and the jib boom on the boat when the mast and sails are removed. A, B and C rigs fit straight onto the booms.

I have machined an alloy stubby, forward vang so we can change the angle on the foot of the mast and the main boom vang has a left a right hand thread, so it can be adjust for upward or downward pressure.

You can view photos at http://www.ec12.co.nz/ec12_boatofthemonth01.htm

Regards Phil

[PaulP]

Phil,
Do you use a radial fitting on the bow or how do you mount the jib-boom?

I've looked at the pictures. How 'bout some closeups

Paul P

[Greg Vasileff]

YES! I agree with Paul. The website is real good looking but it's frustrating that the photos are so small. It would be nice if they were all linked to larger photos.

Otherwise, keep up that great work.

greg V
http://ghmyc.org/

[dave thinel2]

Another source for a solid vang/gooseneck assembly is the one Mike Zellenack makes. It is well made and fuctions well in light air or heavy. You won't save any money but you will save time and effort. he can be found on the supplier page.

[greerdr]

I used this assembly. Go with Zellnack if using goldspar mast.SAVE THE ALLEN WRENCH SOMEWHERE SAFE.[B)]

R.C.Greer

[Doug Wotring]

I vote for the zellanack style vang. I suggest pppitting ball fittings on it as the flanges take a great deal of stress in heavy air

[s vernon]

Doug,

What flanges?

Scott

[Doug Wotring]

the zellanack vang I got had a flange on the boom end of the vang......it does provide a nice clean mounting but due to forces placed on the vangg it puts a great deal of stress on that point.

Pennsylvania guys have put ball joints here

[PegLeg]

Doug

I agree that the Zennack vang is weak at the boom end. Part of the problem is that that end is "fixed" and givesz a very limited range of adjustment before bad things happen (mast bow, broken attachment etc.)

I have modified mine to have a "strap pivot" and it seems to work well. I sure would like to see a picture of the "ball Joint" that you guys use. Possible??

Pete[}:)]