Rigid boom vang on Catalina 310

[MikeToronto]

I have a 310, hull number 315, so obviously the rigid boom vang with no line. Also a topping lift, which appears to serve no useful purpose. Anyway, got the boat in 2018, it has dodger and bimini, and every time I'd take the mainsail down for winter, I'd notice that the aft end of the boom lowers and starts scraping against the top front of the bimini. In the spring, I'd put the sail back on and the boom would rise just enough to leave about 1/2" of space between the bottom of the boom and the top of the bimini. Well, this spring that didn't happen and now I am thinking of raising the boom slightly - but of course the vang won't allow me to do so. Could someone please explain to the novice where and what I need to turn or twist to raise the aft end of the boom slightly? Same 1/2" should do the trick while not screwing up the in-mast furling.

 

[kappykaplan]

How old is the sail? If the leach has stretched, it's easy to see how you gained (or lost) the 1/2 inch.

 

[PaulK]

You leave the mast in and don't adjust the forestay? The sail may have stretched, as Kappy suggests, but do you want to buy new sails? Making the forestay shorter by tightening it and easing off the backstay would be a less-expensive approach.

 

[MikeToronto]

The sail is original, but has been rarely used. Regardless of the leech stretch, I believe lengthening of the vang would do the trick. I just don’t know how to do that.

 

[PaulK]

Extending the rigid vang might work to hold the boom up to clear the bimini when you're not sailing, but if you use the vang-- or even pull the sheet tight with the sail up -- the boom is going to be pulled down into the bimini again because the sail has stretched. You could use the topping lift to keep the boom up to a desired height, but that would make the vang less useful for adjusting sail shape. You would not be able to flatten the sail because the topping lift would prevent the boom from being pulled down any further than your setting.
So... it looks like you can tilt the rig a touch forward by adjusting the forestay and backstay (which might also require extending the vang), or you may have found a use for your topping lift.

 

[LloydB]

Have you double checked to see if you're Bimini frame has been warped up higher 1/2 inch by an unknown undocumented oops?

 

[MikeToronto]

I have. No oops have happened and no warping has been detected. Also, to other advisors - I’ve tried to tighten the topping lift, but the rigid vang won’t let the boom rise. Also, I have a furler as a forestay and fail to see how I can possibly adjust it, nor why I’d do that if I could adjust the vang. Are these vangs adjustable at all and if so, has someone here done that and how?

 

[jdrutten]

I’ve tried to tighten the topping lift, but the rigid vang won’t let the boom rise. Also, I have a furler as a forestay and fail to see how I can possibly adjust it, nor why I’d do that if I could adjust the vang. Are these vangs adjustable at all and if so, has someone here done that and how?

I don't understand why your rigid vang won't let the boom rise? Are you sure the control line has been released? The vang shouldn't be preventing your boom from rising. Nonetheless, I had the opposite problem from you. My sail was stretched with a flappy leech and my Selden Rodkicker was bottoming out. I couldn't tighten the mainsheet enough to get good shape. So I needed to move the end of the Rodkicker aft in order to let the boom fall a bit. I don't know what kind of rigid vang you have, but my Rodkicker is held in place with a movable car which is attached to the boom with a couple bolts (one forward, one aft) which screw into tapped holes in the underside of the boom. On the Rodkicker, you can disconnect the rest of the assembly from the car, loosen the bolts and slide the car wherever you want. After moving the car aft 3 or 4 inches or whatever it was, I reused the prior aft screw hole for the forward bolt, and then just simply tightened down on the aft bolt since I didn't want to bother with tapping a new hole. I don't think tapped holes are required, but they do offer a certain peace of mind.

 

[Scott T-Bird]

Catalinas typically have a Garhauer rigid vang. I don't understand why it wouldn't lift the boom when you release tension on the vang control line. Is it fully extended and the boom is still too low?

The previous owner of my boat built an unusually tall bimini and he had to have his mainsail cut accordingly. I noticed it when I was shopping the boat and accepted it as is - not really a big deal. Perhaps you have a similar situation. I use a topping lift because that is how the dutchman is rigged. Do you have a dutchman system for flaking the sail? That would be the reason for having a topping lift.

There are a number of variables in this question so we really don't know how to answer you. Your vang may not be adjusted properly. Your bimini may be unusually tall. Your sail may need to be cut for a boom that can't be let down to a normal position (if the bimini is too tall). Just because you have a rigid vang doesn't mean that you can't use a topping lift, too.

But first off, there seems to be something odd about your vang if it isn't lifting the boom above the bimini frame when you release tension on the vang control line.

 

[MikeToronto]

Catalinas typically have a Garhauer rigid vang. I don't understand why it wouldn't lift the boom when you release tension on the vang control line. Is it fully extended and the boom is still too low?

The previous owner of my boat built an unusually tall bimini and he had to have his mainsail cut accordingly. I noticed it when I was shopping the boat and accepted it as is - not really a big deal. Perhaps you have a similar situation. I use a topping lift because that is how the dutchman is rigged. Do you have a dutchman system for flaking the sail? That would be the reason for having a topping lift.

There are a number of variables in this question so we really don't know how to answer you. Your vang may not be adjusted properly. Your bimini may be unusually tall. Your sail may need to be cut for a boom that can't be let down to a normal position (if the bimini is too tall). Just because you have a rigid vang doesn't mean that you can't use a topping lift, too.

But first off, there seems to be something odd about your vang if it isn't lifting the boom above the bimini frame when you release tension on the vang control line.

Like I’ve said at the beginning of the thread - I am a relative novice and would like to apologize again for perhaps not being clear or not understanding the advice given right away.
Having said that - I don’t think my boat is rigged with any boom vang control line. I will be at the club on Friday or Saturday and will try to take a photo of the vang, but near as I could see, there is no line attached to it or having anything to do with it. It’s just a metal cylinder attached to the bottom of the mast at fore end and to the underside of the boom as the aft end. No lines.

 

[kappykaplan]

will try to take a photo of the vang,

Yes, please! We should have asked you for photos sooner.

 

[MikeToronto]

Also, for further clarification, I have in-mast furling main, naturally with a loose foot and only attached to the moving car aft.

 

[Scott T-Bird]

Like I’ve said at the beginning of the thread - I am a relative novice and would like to apologize again for perhaps not being clear or not understanding the advice given right away.
Having said that - I don’t think my boat is rigged with any boom vang control line. I will be at the club on Friday or Saturday and will try to take a photo of the vang, but near as I could see, there is no line attached to it or having anything to do with it. It’s just a metal cylinder attached to the bottom of the mast at fore end and to the underside of the boom as the aft end. No lines.

What is the vang model? Catalinas typically come equipped with Garhauer vangs as far as I know. It should look like one of these below.

https://www.garhauermarine.com/product-category/mast-boom-mast-boom-blocks-hardware/rigid-boom-vangs/

It should have a control line. How else are you going to adjust twist? (lifting the boom to loosen the leech). The rigid vang works by having a spring or gas piston that puts upward pressure on the boom to lift it, while a control line opposes that force by holding the boom down. In this manner, the lift of the boom is adjustable. It's not understandable to me that you could have a rigid vang without a control line, unless you have a hydraulic vang, of which I am completely unfamiliar. I suppose a hydraulic vang is adjustable up and down via hydraulics, in which case you would have hydraulic hoses instead of control lines.

In any case, rigid vangs are manufactured to be adjustable so it makes no sense that you can't raise or lower the boom via the vang accordingly. A model of the vang or a photograph is the only way for you to clarify this for us. It would also be more helpful to us if you were to describe the mainsail, whether it is in-mast furling, boom furling, or a standard flaked mainsail.

https://www.catalinadirect.com/images/features/Rigid%20Vang%20Final%20Revision.pdf

 

[MikeToronto]

What is the vang model? Catalinas typically come equipped with Garhauer vangs as far as I know. It should look like one of these below.

https://www.garhauermarine.com/product-category/mast-boom-mast-boom-blocks-hardware/rigid-boom-vangs/

It should have a control line. How else are you going to adjust twist? (lifting the boom to loosen the leech). The rigid vang works by having a spring or gas piston that puts upward pressure on the boom to lift it, while a control line opposes that force by holding the boom down. In this manner, the lift of the boom is adjustable. It's not understandable to me that you could have a rigid boom without a control line, unless you have a hydraulic vang, of which I am completely unfamiliar. I suppose a hydraulic vang is adjustable up and down via hydraulics, in which case you would have hydraulic hoses instead of control lines.

In any case, rigid vangs are manufactured to be adjustable so it makes no sense that you can't raise or lower the boom via the vang accordingly. A model of the vang or a photograph is the only way for you to clarify this for us. It would also be more helpful to us if you were to describe the mainsail, whether it is in-mast furling, boom furling, or a standard flaked mainsail.

https://www.catalinadirect.com/images/features/Rigid%20Vang%20Final%20Revision.pdf

Looks similar to what’s on that web site except there is no control line on it. There’s never been one, perhaps the original owner forgot to put it back when he stepped the mast last (I haven’t taken the mast down since getting the boat).

will try to photograph and look for any manufacturer or model info on it ASAP.

 

[Joe]

The sail is original, but has been rarely used. Regardless of the leech stretch, I believe lengthening of the vang would do the trick. I just don’t know how to do that.

If you're "vang" has no adjustment feature, it's just a strut. In any case, I can't imagine it not having some kind of method to adjust the length.. even it it requires tools. I encourage you to make a first class upgrade to your boat by installing a real functioning boom vang... Garhaurer is the most popular and by far the most cost effective. Buying it directly from the factory would by my suggestion, although they are sold through many online chandleries.$500 or so should cover it..... money well spent, along with an auto pilot and well made dodger.

If you just want to keep the boom from dropping down too low, and you can't use the topping lift or figure out how your existing boom strut adjusts....... tie a piece of thin lined to the backstay above the boom end, using a rolling hitch. 3/16 line is good. If you can't tie the rolling hitch use a strong spring clamp (available at hardware stores). The geometry of the angled backstay will discourage slipping. You can install an inexpensive snap hook to the free end if you like, or just tie it to the boom with a slip knot. The "pigtail" or "pendant" is only for storing the mast so it won't drop on your dodger.

Okay, if the pigtail solution is not to your liking, then just lay a block of wood between the two. A notch on top and some padding underneath the block can offer additional protection to the boom and the dodger. In some circles, this "crutch" method, although supported by the dodger frame rather than being detached and self supporting, is called a "boom gallows" .... pretty cool. heh, heh. Whatever you do, keep that boom from doing damage to your dodger.... a proper rigid vang is much, much less costly than a sailboat's canvas dodger. (if you don't believe me, ask anyone who has ever had one made for their boat... you'll be shocked!) Good luck.

 

[MikeToronto]

While searching further across the web, I've come up with this thread: Rigid Boom Vang and Toping Lift | Catalina 36/375 International Association

The first photo there shows my vang, and the last post of that thread basically describes the reasons for its existence and the suggested way to adjust it. I will attempt to do so this afternoon and report back.

 

[MikeToronto]

On the boat. Eased the main sheet. Twisted “the turnbuckle” that is my boom vang. Went the wrong way first (of course). Reversed, lifted the boom as desired. Tightened the main sheet. Done.
Thanks, everyone. I’d say this is impossible to do with sail unfurled, so would not be useful in a race, but for a cruiser like me - works.