Building your own Paravane System?

[Taras]

Has anyone had any experience building their own Paravane System? I'm talking poles, fish, cables, the whole kit and kaboodle.

I'm thinking this maybe a preferred way to stabilize my vessle based on the fact that they only cause drag when you want to use them. Also, the simplicity and cost are big elements to me.

Obviously engineering the thing the the most important part for safety and structural integrity.

Thanks for any resources/Ideas.

Steve

 

[Phil Fill]

I been up grading, buying and looking at boats that have them. Most of the commertial trawler had/have them, and some of the items I have come off them. So I can copy what they have done.

 

[Marin]

Strength is the key, I think. Lots of pressure applied to both the paravane gear and the mounting system to the boat, and to the boat itself. Lots of leverage to mutiply the pressure and strain.

Maybe the best bet is to study and get specs for the systems used on commercial trollers and trawlers. They often use their trolling poles or trawl net spreaders to deploy birds from. Haven't noticed any paravanes on the purse seiners or gillnetters in our marina, however.

 

[Larry M]

Strength is the key, I think. Lots of pressure applied to both the paravane gear and the mounting system to the boat, and to the boat itself. Lots of leverage to mutiply the pressure and strain.

Maybe the best bet is to study and get specs for the systems used on commercial trollers and trawlers. They often use their trolling poles or trawl net spreaders to deploy birds from. Haven't noticed any paravanes on the purse seiners or gillnetters in our marina, however.

We have traveled probably 10,000 miles with our paravanes deployed. They are easy to build and repair with off the self items. With some basic welding and rigging experience you're good to go.

But before you build it hire the expertise to design the system specific to your vessel. Proper design is the key. The loading is incredible. Each of our fish is ~300 square inches. At 7 knots, in large seas, you can see the stress and the loading. In my opinion, you could do significant damage to your vessel if it is not properly designed. Every vessel is different and one size does not fit all.

 

[Forkliftt]

And build in lots of triangles. The strongest shape on earth!

 

[Sisuitl]

Most of the commercial systems I've seen weren't signed off on by an engineer and seem to work fine, but yeah, the loading can be disconcerting. Some reading that might be useful:

Bulletin No.: 15/2000 - Transport Canada
http://publications.iot.nrc.ca/documents/IR/IR-2007-10.pdf

There's a number of incidents involving paravanes in the TSB marine incident reports but for the most part they aren't relevant to what you're doing, unless you want to start filling your cabin with fish or climbing along the outside of the hull to recover the paravanes. (Why was that even an acceptable idea?)

 

[ben2go]

Has anyone had any experience building their own Paravane System? I'm talking poles, fish, cables, the whole kit and kaboodle.

I'm thinking this maybe a preferred way to stabilize my vessle based on the fact that they only cause drag when you want to use them. Also, the simplicity and cost are big elements to me.

Obviously engineering the thing the the most important part for safety and structural integrity.

Thanks for any resources/Ideas.

Steve

Stabilizers - Products

 

[Vyndance]

The booms are pretty straight forward. I think the mast design for a GRP boat not designed for one would be the biggest drawback. There is a 46 Nordhaven that lives next to me and the rigging is substantial.

 

[ben2go]

The booms are pretty straight forward. I think the mast design for a GRP boat not designed for one would be the biggest drawback. There is a 46 Nordhaven that lives next to me and the rigging is substantial.

I am not very familiar with paravane systems,but I do understand how they work and what they are used for.Even tho the vanes are around 60 pounds,the leverage put on the hull through the poles is substantial.This would be one system I would over build.

 

[ben2go]

Check these out.


Amazon.com: Magma Rock-N-Roll Stabilizer: Sports & Outdoors

 

[FF]

Most costly/complex part is for my boat the mast must be lowerable.

Chose to make a lower HD SS tube that mounts with an inner tube that can be lifted to the required height.

A slight PIA , but far better than changing the air draft from 10ft 6 to 20 ft , and waiting for bridges as we do with a sail boat.

FF

 

[Aquabelle]

I cannot find the reference just now, but a few years back PassageMaker had an article on the pros and cons of build your own paravanes and how to go about working it out. But I agree with ben2go above: I'd never do it. These days there are better....and much less dangerous...solutions out there, albeit at a cost.

 

[Phil Fill]

Check these out.


Amazon.com: Magma Rock-N-Roll Stabilizer: Sports & Outdoors

Those are for anchoring or at the dock. On Lake Union we were close to the speed/test area so we got a lot of big waves, so I hung roll stabilizers which are plastic cones. Cost 10 bucks/cone.

I was think, why not just hang the fish stabilizers from the cleat of the boat like I did for the rocker stoppers?

 

[skipperdude]

I cannot find the reference just now, but a few years back PassageMaker had an article on the pros and cons of build your own paravanes and how to go about working it out. But I agree with ben2go above: I'd never do it. These days there are better....and much less dangerous...solutions out there, albeit at a cost.

That is it in a nut shell.
The cost and something else to go wrong.
Low tec is always better in my book.

Dangerous?? Been running mine for 10 years never had an issue.

Paravanes about as low tec as you can get.

If there was a big problem with them you would think thousands of commercial fishing boat's would do something different.

A lot of thesr guy's work alone especially the Salmon trooling guy's

Walk the dock's sometime where the commercial guys work out of.
You will see hundreds of Paravanes of every make model and configuration.

If you are rich with thousands of dollars to throw at your boat. Get a set of fins or a seagyro.

Better yet buy a new boat that already has stablizers.
It's only money.

If you have a problem Fix it. You can work on them yourself.
ever try to work on a set of Nadias or a sea gyro thingy.

Like I always say. If you can't repair it maybe it shouldn't be on the boat.

SD

 

[markpierce]

This trawler with an apparently-customized paravane set up arrived at our marina a couple months ago. May provide ideas for doing your own.

 

[stevensibs]

Larry, could I beseech you to send me closeup photos of your paravane hardware, cables, poles and end-caps, etc?? I am going to build a pair for my 42 footer. Also, are the poles aluminum or stainless?, What thickness/diameter? I hope this is not over extending my welcome but 've searched everywhere to no avail.

 

[hollywood8118]

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

 

[Keith]

I bought the plans to add some to my Krogen 42, but never have. The first problem is that you have to lose the mast, so you lose the ability to fold that down. They are well engineered though, and there are some parts that need to be installed below the outer decks to spread the load. Like someone else mentoned, these things will put tremendous strain on your boat and you need to know what you're doing or hire someone who does before you rip stuff off of your boat.

 

[Larry M]

A commercial fisherman in the PNW designed ours then another KK owner customizeed them. Unfortunately all the plans were lost in a fire that the KK owner had. Here's what I can tell you and a few pictures.


All the poles are Al. The A-frame is 3 1/2" d and the out riggers are 2 7/8" d. Both have 5/16" walls. The fish are 15' below the surface at rest. They can not foul the running gear. From the tip of the out rigger there is 8' of 1/2" - 3 strand nylon (for stretch/shock loading) then 13 1/2' of 1/4" SS wire then 4' of 1/4" SS chain (to help with retrieval) which is attached to the fish.


If there's anything specific let me know. Your timing is good. We are reinstalling everything this weekend after repainting.

 

[stevensibs]

Thank you very much Larry. It helps a lot. Love your boat.

 

[Larry M]

Steve: Glad I could help. If you make them out of Al. Put a bushing on the outrigger at the tab from where the fish hangs. We almost lost the fish because of wear. We had a metal shop fill the hole, re-drill and add a SS bushing. The tabs are 1/2" Al. This was the only wear point.

 

[Tad Roberts]

Nice job with the description and photos Larry, thanks

One thing that's not obvious in the photos (of the Nordic, Krogen, or Volunteer) is some form of hold-down for the poles. If you take a huge roll and the upper vane unloads the pole can flop inboard with a crash....... The commercial guys in BC use two pieces of pipe in a scissor arrangement off the mast, which is clear of everything. Beebe advocated a tackle to an eye down near the waterline which is less desirable.

 

[hollywood8118]

Nice job with the description and photos Larry, thanks

One thing that's not obvious in the photos (of the Nordic, Krogen, or Volunteer) is some form of hold-down for the poles. If you take a huge roll and the upper vane unloads the pole can flop inboard with a crash....... The commercial guys in BC use two pieces of pipe in a scissor arrangement off the mast, which is clear of everything. Beebe advocated a tackle to an eye down near the waterline which is less desirable.

The entire fish would need to come out of the water for this to happen... could it..possibly... likelihood.. not too much. Mine had no hold downs and there was never an issue.. Keep in mind the commercial guys will deploy the poles without vanes as the poles alone will help slow the roll when they work in the trough, for this you need to be able to lock them down.
I had the boat in BIG water a couple of times that I never want to experience again.. on anything less than 200'...Para vanes work great.. they rarely fail and need little maintenance. My next boat will have vanes unless the P.O. has paid for the cost of a active system. One thing I want to research is a system that allows the fish to be pulled without completely stopping the boat and lifting the poles
HOLLYWOOD

 

[Searios]

have a look at this Nordhaven 46 stabilizer system. Its my favorite design.

Paravanes
Flopper Stoppers

 

[Larry M]

One thing that's not obvious in the photos (of the Nordic, Krogen, or Volunteer) is some form of hold-down for the poles. If you take a huge roll and the upper vane unloads the pole can flop inboard with a crash....... The commercial guys in BC use two pieces of pipe in a scissor arrangement off the mast, which is clear of everything. Beebe advocated a tackle to an eye down near the waterline which is less desirable.

We have no hold downs for the poles. I have seen the scissor arrangement on commercial vessels and they look interesting. Beeb's "tackle to an eye", I don't think would be affective for us. The bracket that holds the poles at the hull is only 32" above the water line. It might be an easy mod for some Nordhavens. Some of the poles are attached at the hull 6 or 7 feet off of the water.


We have had the fish come out of the water though on probably 6-8 different days all on similar sea conditions. We would be running in large beam seas with wind driven waves on top. Hobo would be on the crest and would roll/twist as the wave/swell would pass under us. As this happens, the fish and Hobo are not tracking parallel and rarely, the windward fish would "pop" out of the water maybe a foot. The fishes re-entry is surprisingly smooth but it still "rattles" the poles a bit as well as ourselves. If it continues we head off or slow down. The poles have never moved and I hope, we are never in sea conditions that they do.

 

[Larry M]

...Para vanes work great.. they rarely fail and need little maintenance. My next boat will have vanes unless the P.O. has paid for the cost of a active system. One thing I want to research is a system that allows the fish to be pulled without completely stopping the boat and lifting the poles
HOLLYWOOD

Hollywood: I agree on how great paravanes are.

Let me know if you find a way to retrieve the fish without completely stopping. We can deploy and retrieve the fish with the poles out.

 

[Marin]

FWIW here are some cell phone shots I just took of the Nordhavn 46 that moved into a slip on the new G-dock across from us. To say its paravane system is well-designed and strong enough for the job is an understatement. Perhaps the layout will give others on this thread some ideas.

 

[Larry M]

Always nice to look at other systems, thanks. Storage of the fish could use some improvement on the Nordhaven though.

 

[Tidahapah]

Hopefully sometime early this year I will be going thru the process of fitting a set of paravanes to Tidahapah.
I presently have aluminium arms with flopper stoppers but want to upgrade to full paravanes.
There is also the possibility of fitting a sailing rig.
I will see how things go and if it goes ahead will document it.
There are some very early posts re paravanes and I have some printed documents re the set up etc for paravanes.
These are on another computer at home.
Should have them available when I get home from work in about 3 weeks.
Cheers
Benn

 

[Searios]

Hollywood: I agree on how great paravanes are.

Let me know if you find a way to retrieve the fish without completely stopping. We can deploy and retrieve the fish with the poles out.

The system described in post 24 can also be deployed and retrieved underway