Building your own Paravane System?

[QB]

One thing that's not obvious in the photos (of the Nordic, Krogen, or Volunteer) is some form of hold-down for the poles. The commercial guys in BC use two pieces of pipe in a scissor arrangement off the mast, which is clear of everything.

In case anyone is wondering what Tad is talking about, here's an example of scissor holddowns on a BC troller's poles:

 

[FF]

Should one snag the bottom or a log or a sea land container , something has to let go.

Good design would suggest that what lets go is easy and cheap to replace.

A piece of line would seem ideal . Inspect the various designs to see what the break point is.

 

[funangler]

When I built my poles they fold back not up used 10 ft aluminum square tubing. My biggest problem was harmonic vibration solved the problem with a rubber gasket on the hinge. I manual retrieve the fish with a boat pole walking them back to the stern at slow speeds.

 

[skipperdude]

The Paravanes on my boat look home made.
I will take some pictures of the set up this weekend and post them on monday.
A simple set up.
The biggest issue I can see is a way to store the poles.
You are going to need some sort of mast to hook them onto when not deployed.

SD

 

[FF]

You are going to need some sort of mast to hook them onto when not deployed.

We prefer to lay them down as the air height of the boat determines weather you slip under a bridge , or wait for the next hour or the train to go by.

 

[mizzkim]

Hi. Have you made any progress on your project yet?? I am thinking about doing the same thing with my 35 sundeck. I think the biggest problem I see so far is location front to back. Terry in Alaska.

 

[markpierce]

This visiting recreational trawler transited from the PNW to California had a paravane rig.

 

[boatpoker]

I'd suggest anyone adding paravanes read the Transport Canada Safety bulettin on the issue.

The purpose of this Transport Canada Ship Safety Bulletin is to caution the operators of vessels which are equipped with this type of roll damping system against the hazards associated with their use such as, reduction in vessel's stability, system failure from poor maintenance and operational hazards. read more

 

[Tidahapah]

Well I have removed the poles for my flopper stoppers and am in the process of having fabricated / modified a set of s/s paravane poles.
The originals came of a sister boat belonging to a mate of mine.
he has upgraded his sail rig and paravane set up.
I have 2 sets of fish that I will play with when the time comes.
I am still looking for a 2 nd had rig to fit the boat.
It may be ketch riged or just a main mast and then a gallows set up for the paravane mount.
All still in planning , pre build stage at present.
Off to NZ tomorrow for the Napier Art Deco festival and a bit of trout fishing and then back to work.
Will continue with the project late March when I am home again.

Mark, that is a nice looking little boat but would rather see the poles mounted from the moulding (rub rail) than the cap rail. Would make the set up a lot stronger. Normally the moulding is thru bolted in the deck beam so a lot of inherent strength is built in.
Just my 2cs worth
Cheers
Benn

 

[FF]

If you take a huge roll and the upper vane unloads the pole can flop inboard with a crash....

This is easily solved by angiling the pole up from fairly horizontal.

Sure it might reduce the effective length a small bit but the foreguy and afterguy will work as a down haul since they have an effective working angle .

 

[Peter B]

I'd suggest anyone adding paravanes read the Transport Canada Safety bulettin on the issue.

The purpose of this Transport Canada Ship Safety Bulletin is to caution the operators of vessels which are equipped with this type of roll damping system against the hazards associated with their use such as, reduction in vessel's stability, system failure from poor maintenance and operational hazards. read more

Interesting. I have often had similar concerns. These days, if I could afford an ocean capable boat, and it did not have active fins in good condition, then I would go for gyro stabilisation. The cost has come down quite a lot.

 

[funangler]

When I built my system I decided to be really simple poles go back not up. The arms only 10 foot long And everything can be retrieved by hand with a boat pole. I've been really happy with it.

 

[FF]

On a new build I would install a wide centerboard trunk, and power a board as a vane would be .

A thousand years of CB trunk building assures a tight boat

and the usual CB kick up on grounding would be better than vane holes in the hull.

 

[Trawler_traveler]

paravanes

Paravanes do put a significant load on the boat, the mast and the poles are in compression when the boat rolls either way. The resistance pressure of the fish greatly increases when the boat rolls away from the fish and it tries to dive. It always amazed me at the dampening effect when we were at cruise speed in big seas.. especially as Volunteer was a 60,000 boat. The P.O had rigged her with s.s. cables with a 4' triple braid shock line from the poles to the fish. It seems most use chain as it is easier to deal with and the chain doesn't saw into logs the fish pick up (this happened to me and it was a P.I.T.A. to cut the log loose ). The poles on Volunteer were galv. steel, 2.5" dia. and about 3/16" wall. I wouldn't be shocked to find the fish exerted 750-1000 lbs of force at 7+ kts as the strain on the rig felt significant. In the attached pic you can see the fish on the roof of the aft cabin , the poles and their attachment points, and the mast and associated rigging. I never felt they were a safety hazard.. but keeping enough depth at the fish is critical. If you are in big seas and a fish comes out of the water it gets ugly really fast

HOLLYWOOD

In your picture it looks like the pole topping lift (?) attached partway up the mast, not at the masthead. I must be looking t it wrong ?

(beautiful boat)

-Sven

 

[Trawler_traveler]

I bought the plans to add some to my Krogen 42, but never have.

Where did you buy the plans, were they a standard option for the design ?


-Sven

 

[ben2go]

Where did you buy the plans, were they a standard option for the design ?


-Sven

Some info here. Products - Stabilizers - Kolstrand

 

[hollywood8118]

In your picture it looks like the pole topping lift (?) attached partway up the mast, not at the masthead. I must be looking t it wrong ?View attachment 158377

(beautiful boat)

-Sven

you do know this is from a thread from 2013?. I was looking at this pic and thought i recognized that mast. the pole lifts with the blocks you see were only for lifting the poles. there was a stay to the top of the mast that took the load when the poles were deployed. Still wish I had the boat, she was remarkably fuel efficient and really comfortable. The rig worked really well.
Hollywood

 

[Trawler_traveler]

you do know this is from a thread from 2013?. I was looking at this pic and thought i recognized that mast. the pole lifts with the blocks you see were only for lifting the poles. there was a stay to the top of the mast that took the load when the poles were deployed. Still wish I had the boat, she was remarkably fuel efficient and really comfortable. The rig worked really well.
Hollywood

Ha, yes, the Internet never forgets.

I thought there must stays to the top but I couldn't see them. We may finally have found a welder who could fabricate our poles so I'm out looking for any ideas I haven't already seen. Our Shiplet is about the same displacement as your Volunteer (56k at 41' l.o.d.) so similar loading, nothing to skimp on.

Thanks for the answer.

-Sven

 

[Trawler_traveler]

Some info here. Products - Stabilizers - Kolstrand

Thanks. I've looked at that picture before and wonder where they got it. The "experts" like Beebe say that the poles should be at ~85% of the l.w.l. behind the bow or they will fight the boat pitching too which is a lot more load and drag.

I thought I'd seen someone who made aluminum fish but now I can't find them.

Appreciate the info.

-Sven

 

[Snapdragon III]

I will drop this here even though it's an old thread incase anyone finds it useful in the future. My old boat had very effective paravane stabilizers that had a unique center mast set up. I never did it, but it was set up so you could release the stays and fold the mast down on the cabin top. The poles could lower, and rotate back to store along the gunnels. It was originally rigged with 3 strand nylon down to the waterline, then SS cable from there, to the fish. I changed it to thick spectra to the waterline, and thinner spectra from there to the fish. the spectra seemed way better. It was easier on the hands, and broken strands wouldn't cut you when pulling in the fish. I also felt like it would be much easier to cut loose in an emergency, although I never had one that required it. Also, it was unclear to me why the stretch of the 3 strand would be desirable or required. When rocking side to side, the boat just didn't change directions that fast. It never seemed like it was shock loading at all with the pure spectra. The only place I saw it a little was when using them as flopper stoppers at anchor with large aluminum plates instead of the fish. It was a little noisier than the nylon, but more effective, and nothing I was worried about harming the boat or rig with. The stretch, and associated twist of the 3 strand caused chafe/tangling issues with the retrieval lines I attached to the lines to make it easier to get the fish back in the boat. It also cased twist issues when used with plates at anchor.

The only scenario I can think of where the stretch might help is if you were to catch a fish on a huge log or rock or something. My hope was that by using thinner spectra on the portion in the water it would create a weak link that would be the first point to break in that kind of scenario