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Guys I need to find a way to protect fish from the prop that is as economical as possible.


This was the smaller of two we had yesterday

Well the props are pretty far below the hull so after looking around and seeing nothing that looks like what I need on line I started starring at the hull and the lowest Tec way and least expensive way I could figure out is simply bolting a aluminum plate the to rail and another just under the hull bolt them on and drill a 2" hole through them plates and drop a long 2" aluminum pile through that will extend below the props by a foot.

I'm using the spring cleat to secure the head to and then tie the tail to the stern cleat and do not want the fish in the prop it's pretty close and think the pipe might work then just pull it out after I release the fish.

The purpose is to place 5-6 year tags on the for real time tracking.

Keith- I onderstand what you are trying to do, and it sounds like it might mork. A couple of thoughts; I am assuming that the lower guide will be placed right at the chine and thru bolted, is that correct?

- the guides need to be properly backed and the hull reinfoced in those area. especially the lower guide, it will have a lot of force and a lot of levereage loaded on in when an 800 lb mako decides it doesn't want to lay up against it. That coming losse or ripping out could be a disaster in some many ways- leaking boat, flailing 2" pipe hitting you in the head, etc.

- rather than just 2" holes thru the plates I wuouol like over sized hole in the top plate and a sleeve about 2 or 3" long on top with a 2" ID. Then that is welded welded into the plate. Why you ask? 1st your poles and the plates will last longer, 2nd because you need to have a cross pin in that top bushing to hold that pole down. When the fish roles against it or rises and flails against it or if a fin gets under it then that pole may raise up and then- someone may get whacked or - the fish might pass under it and be trapped. both very very bad.

- a foot below the props sounds good, you might even go more, the last thing that you want is a fish or a line to somehow get behind that pipe while it is alongside, that would defeat the whole purpose and cause more injury than the props alone. It probabky sounds stupid, like the fish could never get past the pole, but like you I have seen these fish do some incredible things!

- an aluminum pole might bend easily with all that levereage sticking below the lower guide, think about steel tube

- also consider how that the effect of the assymetric drag that guide will have on the boat, I thought about putting a bushing in the lower guide also but if it is in the water it will add a lot of drag.

I have a few other ideas acout it but I am running my wife to the farmers market

Keith wouldn't it be cheaper to put somebody on the bridge to keep the fish behind the boat instead of under it. I don't understand structural integrity like many here but that seams like 60 miles out and a hole in the bottom of the hull to me! Charlie Foxtrot of the first order.

I am not sure about the poles...lots of leverage with possibility of fish getting on the wrong side...go deeper and get more drag.

The nozzles shown...great for workboats with right setup.


Another idea...but creates lots of drag. I used to fish on a customers commercial boat in NY harbor for bass in the early 80's. Place was loaded with debris...floating truck tires, 55 gal drums, phone poles, parts of piers... Running at night with a rope autopilot on a 26' open boat in the middle of the night at cruise had us hitting stuff all night long. What he had done, bolted SS tubes along the bottom like strakes that bent outward encaging the running gear. He lost a knot or two at cruise but never bent another shaft, wheel and hull had less chunks missing each season. Just a thought...but you would need two...he was a single diesel.

Carl and Mark, you are both saying what I was trying to say , but more clearly than I could. i mean, man that is a lot of leverage hanging over the side of the boat having a lot of force applied. Can you imagine the S%*t show that would ensue if the anything ever let loose on that? Hole in the hull? Maybe. Someone getting their melon smashed? Maybe. I understand what Keith wants to do, it just really needs to be thought out and thought thru before doing it so that what he ends up with really works. Because you know he is going to do something, that is how he rolls.

I am thinking of a few other ideas but i want to hear back from Keith first.

Keith, the parasitic drag that would be introduced by nozzles would turn your boat into a displacement speed boat and would defeat the purpose of having a planning hull like the 31. The other rig seems pretty cumbersome. How many sharks have you hurt with the propellers? The solution here seems to create a bigger problem. Jet drives may be a solution,. but that is a whole lot of money and you lose efficiency. I think the suggestion of hiring a mate might be the best one...

If you are looking for something that would be a temporary rig maybe some kind of fabric cover that you could deploy from the bow like a big diaper affixed to cleats forward and aft, use weights to sink the forward end when retrieving it and pull it back up over the transom., you would not be able to manoeuver with that deployed though.

I wonder....

How about a Polycarbonate Foil?
Kind of a centerboard like used on sailboats.

A sheet of Polycarbonite 1/2" thick or so with a pivot point up high on the gunnel....away from waterline. Being fairly thin compared to a Pole or tube it would have less drag and it would only have a single point of resistance. I'd beef up the pivot by adhering a few support plates to each side and then install a bearing. Could be held down several ways mechanical ways or get creative and add wings like a planer board.
I'd consider making it a break-away style if going mechanical should you hit something.

Just a thought.
Carl

How about a flip down pipe cage that is secured to the transom with pad eye hinges. Flip it up against the transom for running, down for fishing. You could use the same cleats to hold it up or down. Sort of like the flip out pipe extensions you see on pickup tailgates.

Hey Guys I am bringing the fish along side then cleating them off on the spring cleat then tail roping them at the stern cleat then attaching the tag to the dorsal.

Keith, lobster men up here in New England use a prop cage to keep from cutting off the pot lines as they haul in the gear. BH

Where can I get one ?

The purse boats for the menhaden fleet here use them to, but they are chunky locally built contraptions that would not allow you to plane. That is why I suggested a flip up type setup so you would not affect the handling and performance of the hull.

Keith, Rawleigh is right on the cage is built for displacement hulls, how slow do you want to go? I like the flip down idea or to get the sharks head more forward with a pulley system to keep them out of the wheels and only use the pt engine if you tag from the stbd side. BH

Keith Poe wrote:Where can I get one ?

You make them...
or you have them made.

Basically what I mentioned earlier...bunch of Tubes/Rods that are placed around the running gear.

http://www.trawlerforum.com/forums/s6/p ... 335-2.html

Scroll down to post #29.... This is the basic idea....since we do not run keels the tubes would be bend following the hull lines and bubble out around the prop.

Creates lots of drag...but protects well.