Hobbyhorsing: something like a flopper stopper?

[hpeer]

I had an incident in St Pierre that caused hobby horsing on anchor. For a few hours we had a wind over current situation; or more precisely the wave set was coming in from the opposite direction of the current. This caused some short steep waves that while not real big were causing the boat to hobby horse badly.

It was somewhat dramatic, not uncomfortable in the saloon but not good in the aft cabin. And I just did not like it. The waves were coming from dead astern.

I deployed a drogue. The bare drogue did little as it simply streamed astern. I then added a 15 pound weight to the drogue so it would not stream as far aft but be more vertical, and that did a fair amount to settle the motion, maybe 50%.

[KP44]

Originally Posted by SVKemily

Hobbyhorsing. Sorry, by "concentrate ballast near the beam" I meant concentrate it in the middle, between the bow and stern. Still working on my nautical terminology.

Thanks for the responses so far! I will definitely try to concentrate any weight I add in the middle, and good to know that adding a flopper stopper at the bow won't cause anything terrible to happen. Any other tips and tricks?

Your terminology is correct. The beam is the widest point of the ship, perpendicular to the centerline or keel. The maximum beam will usually be near the center of buoyancy.

[rslifkin]

Originally Posted by hpeer

I had an incident in St Pierre that caused hobby horsing on anchor. For a few hours we had a wind over current situation; or more precisely the wave set was coming in from the opposite direction of the current. This caused some short steep waves that while not real big were causing the boat to hobby horse badly.

It was somewhat dramatic, not uncomfortable in the saloon but not good in the aft cabin. And I just did not like it. The waves were coming from dead astern.

I deployed a drogue. The bare drogue did little as it simply streamed astern. I then added a 15 pound weight to the drogue so it would not stream as far aft but be more vertical, and that did a fair amount to settle the motion, maybe 50%.

That brings up a good point. Just about every hull has some set of conditions that will make it misbehave in some form. It just takes some time with the boat to determine how often some problems show up and how much effort it's worth to solve them.

[Hudson Force]

SVKemily,
It's my understanding that this hobbyhorsing is only troublesome in the slip under occasional wind and wave conditions and this makes it uncomfortable while you are aboard.

If this is the case, a very simple solution may be to simply drop your anchor and some chain straight down from your bow while in the slip. By doing this, every rise of your bow will be countered by lifting the chain. Added buffering of this rocking may be achieved by adding weight to the chain or adding a second anchor tied to a rope rode.

I never did this often, but found it to be a cure more than once.

[SVKemily]

Hi everyone, thanks so much for the additional anecdotes and ideas, and for the kind words about my boat! I think she looks nice too. I will definitely have her weighed next haulout and try the anchor idea next time hobbyhorsing becomes excessive in the slip. And in a pinch I'll sleep amidships and think positive thoughts.

I'm feeling optimistic at this point. I have several plausible hobbyhorsing countermeasures in my pocket, and am now hopeful that the 5" above waterline issue has a reasonable explanation, eg the water tank is bigger than I think. Also, although the waves weren't bad in the marina when I visited the boat today, I did notice that when I redid my docklines with snubbers I just bought, they stopped creaking and my perception of the boat's motion was substantially reduced simply because the noise wasn't stressing me out anymore. Thank you all so much for all of your help!

[Don C L]

You have a really wonderful boat. Once you get more sailing time in, her little quirks will not bother you anymore because you will be appreciating her finer qualities... and you'll be used to the little rocks and rolls... you may even grow to like them!

[JPA Cate]

And, stretchy dock lines always helps! Ditch the old jib sheet ones, and use some three strand nylon, for a huge improvement...if you're using old halyards or sheets.

Ann

[nofacey]

Fill the fuel tanks

[Nicholson58]

Originally Posted by BillKny

While true literally, a boat without a lot of weight in the ends typically has a "hobbyhorse" frequency that is much faster than large waves. The small waves that match the resonant frequency tend not to impart enough energy to get the boat moving much, if at all.

The lower frequency of a boat that is heavily laden at the ends more closely matches with the larger, longer waves. When the the frequencies of the boat and the waves come close together, the system resonates and moves a LOT more.

Spot on.

Get the weight centered as much as possible. Smaller chain or shorter can make a big difference. Catamarans naturally have the ground tackle centered. Monohulls should have the windlass in front of the mast with a chain locker at the foot of the mast. Could be easily done using a length of heavy large PVC pipe from the deck to the hull. Obviously, not easy on old boats due to hatch placement etc. Our 58 foot tank carries 1500 pounds of combined tackle in the bow. Reducing 320 feet to 200 feet of chain made a big difference.

[nfbr]

I found a very interesting comment in The Venturesome-Voyages-of-Captain-Voss from the 1800's talking about stability, where he would lift weight higher in the boat to stabilise it. It didn't make sense to me, until I really thought it over. My uneducated analysis of his comments is if the weight is too low, the harmonic / rocking frequency is high / harsh. By increasing the CG height, you make for a much lower harmonic frequency, potentially decoupling from wave state, and improving comfort / possibly reducing loads on rigging. Just need to be careful how that impacts rollover stability.

[Sofa King Fishy]

I think it mostly depends on the seastate- what’s your average depth? it’s a well designed, heavy vessel, but those old school hulls tend to hobby horse a lot in shallow, choppy waters. I sail the Chesapeake Bay & you can see noticeable seesawing with those older spoon hulls.

[Thumbs Up]

Originally Posted by Sofa King Fishy

I think it mostly depends on the seastate- what’s your average depth? it’s a well designed, heavy vessel, but those old school hulls tend to hobby horse a lot in shallow, choppy waters. I sail the Chesapeake Bay & you can see noticeable seesawing with those older spoon hulls.

These boats are more salty.

[Icarus]

Originally Posted by SVKemily

Hi everyone,



I have noticed that my new (to me) Mason 32 hobbyhorses (or pitches, or rocks fore-and-aft) quite a bit more than neighboring boats in the marina. I understand that the spoon bow shape can be especially prone to hobbyhorsing.



The previous owner has told me that when loaded for cruising it sits about 5" lower in the water, which means it would have displaced approximately 3700lbs more. From what I have read, concentrating that extra ballast near the beam could reduce hobbyhorsing.



I'm wondering whether it's possible to supplement the effect of that ballast with something like a flopper stopper, deployed off the bow or stern. I haven't found any accounts of anyone trying this, or any recommendations for or against.



Has anyone tried it, or does anyone have any non-ballast hobbyhorsing countermeasures to share?



Thanks in advance!

Flopper stopper.? Really?

[Bill_Giles]

If you are in a Marina and are hobby horsing when tied up then there are waves or swell entering the marina. Try turning the boat around. If that does not cure it then ask for another, quieter, berth.