Boom Height when using a Rigid Boom Vang (keep the topping lift?) E33RH

[sf1332]

I finally installed a rigid boom vang from Garhauer (see photo below). Believe it's excellent quality, and overall, dealing with them was easy and fast. To be honest, they just ask me for few dimensions, and they made it, and then I did have to send a pice back for adjustment...still easy.

After installation, I eased out the topping lift, and let the whole weight of the boom rest on the new vang. The boom lowered (no mainsail installed) certain amount below 90 degrees (vs. the mast)...but not sure how many degrees. My question is what is the optimal descent angle at rest? (presume later, mainsail installed with more weight). Is there such optimal angle?

Garhauer probably uses the same spring load measurements for all the boats in similar size...but my mainsail is usually large for a 33' boat and boom also longer and heavier than most 33' boat). Does this mean perhaps the Garhauer vang might be too weak to support the boom (+mainsail) weight?

Finally, I decided to keep the topping lift, but wondering if I've made the right decision. The main reason is that I have a bimini that can not be opened unless the boom is raised to certain height. If I ever want to use the bimini while sailing, a topping lift seems to be needed to make sure the boom would not drop down to the bimini frame.

 

[Slick470]

We have a rigid vang and no topping lift on our Ericson/Olson 911. The boom does not sag at all when the mainsail is dropped. This is consistent with other boats that I have sailed with rigid vangs. Maybe there is an adjustment on yours that would allow for that? If not I'd call Garhauer to see if they have any suggestions, or maybe a heavier duty spring?

 

[Loren Beach]

We have a spring-return vang. When it sagged a bit after some years we were able to extend it and reinsert the pin at a different thru-hole on the tube.
So do call Garhauer. I betcha they have a similar scheme for this.

 

[bigd14]

Are you able to get at the spring to see what its force rating is? I went round and round with this issue on a Selden vang that came with my boat. The spring had seized in one position and would not budge. The nameplate on the spring was corroded so I had to guess at the force. I guessed at 550 pounds and when installed the boom went shooting up in the air and couldn't be pulled down without a big effort on the mainsheet. I ended up 2 springs later at 350 pounds. This is enough to easily lift the boom with loaded sail on the 30+. I don't know if the configurations between our vangs would be similar, but hopefully this will help with your calculations.

BTW I got my springs at McMaster-Carr. https://www.mcmaster.com/catalog/128/1396

 

[Christian Williams]

I decided to keep the topping lift

I figure Garhauer will get you a proper boom height for the Bimini. And most folks do remove the topping lift.

There is, however, a secondary purpose for a topping lift. In a seaway, when the mainsail is reefed or furled in heavy weather, the boom can be set absolutely rigid when the TL and mainsheet are tightened and a side line is rigged. Such a bar-solid boom is useful when moving about the deck in dicey conditions.

I'm under the impression that a spring-loaded vang cannot offer such absolute stability.

 

[Loren Beach]

I'm under the impression that a spring-loaded vang cannot offer such absolute stability.

Correct, you are.
When we lower our main, we move the halyard shackle to a ring on the end of the boom. Then sock up the halyard tight against the tension of the mainsheet. Then it's safe to lean of the boom again.

 

[sf1332]

We have a rigid vang and no topping lift on our Ericson/Olson 911. The boom does not sag at all when the mainsail is dropped. This is consistent with other boats that I have sailed with rigid vangs. Maybe there is an adjustment on yours that would allow for that? If not I'd call Garhauer to see if they have any suggestions, or maybe a heavier duty spring?

There seems to be no adjustments at all. I have sent an email to Garhauer and will follow up with a call later. I wonder if any other Garhauer vang owners have had similar issues. Thank you for your reply.

 

[sf1332]

We have a spring-return vang. When it sagged a bit after some years we were able to extend it and reinsert the pin at a different thru-hole on the tube.
So do call Garhauer. I betcha they have a similar scheme for this.

I presume you have a different brand? My vang does not seem to have any adjustment pins or even a way of opening it (looks factory "sealed"). Thank you for your reply.

 

[Loren Beach]

We bought ours from the designer/builder, a machinist in Portland, back in the 90's. He sold his design to Hood, and they have been marketing it ever since.

http://www.hoodyachtsystems.com/pdf%20files/vangdata.pdf

Trivia: the factory vang on our boat was a gas-return solid vang device. It had lost pressure and the boom was sagging when we bought the boat. Looked like a poor idea to me, or the design was just poor, or the vang builder lacked good QC.

 

[sf1332]

Are you able to get at the spring to see what its force rating is? I went round and round with this issue on a Selden vang that came with my boat. The spring had seized in one position and would not budge. The nameplate on the spring was corroded so I had to guess at the force. I guessed at 550 pounds and when installed the boom went shooting up in the air and couldn't be pulled down without a big effort on the mainsheet. I ended up 2 springs later at 350 pounds. This is enough to easily lift the boom with loaded sail on the 30+. I don't know if the configurations between our vangs would be similar, but hopefully this will help with your calculations.

BTW I got my springs at McMaster-Carr. https://www.mcmaster.com/catalog/128/1396


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As far as I can tell, Garhauer does not provide any technical specs on their website thus not able to tell the force rating is.

I have the RV20-1 SL vang, and it says it's for boat sized 28' to 44' on Garhauer Marine website (https://www.garhauermarine.com), thus I believe it should be able to handle boom size/main size bigger than my 33' boat.

What's baffling is that, (unlike Seldon), there's no pin adjustments, and it seemed to be sealed from factory and the owner cannot/should not adjust inside of the vang.

Thank you for your reply.

 

[sf1332]

I decided to keep the topping lift

I figure Garhauer will get you a proper boom height for the Bimini. And most folks do remove the topping lift.

There is, however, a secondary purpose for a topping lift. In a seaway, when the mainsail is reefed or furled in heavy weather, the boom can be set absolutely rigid when the TL and mainsheet are tightened and a side line is rigged. Such a bar-solid boom is useful when moving about the deck in dicey conditions.

I'm under the impression that a spring-loaded vang cannot offer such absolute stability.

That makes perfect sense. There's no downforce locking mechanism in rigid boom vangs (as far as I know), thus keeping the boom steady without the topping lift seems impossible. Thank you for your reply.

 

[Loren Beach]

A cautionary note: even if you could "lock" the vang into position, you would then run the risk of someone putting their weight on the end of the boom and bending the boom at the vang attachment. That's also why we always attach the main halyard to the boom end when not sailing.