T-top Crab puller question

[Sea Shift]

Here's the deal. I have come up with this great idea :idea: on how to mount a crab puller off of the super stucture on my 265 express. Basically I will be using the back leg that supports the roof. It seems like enough. Let me know what you think. Is the stock 2" support strong enough? What about the bottom support, good angle? I was also thinking about running a rod toward the bow to take out any twist that might occure? Any help would be appreciated. Thanks.

 

[ocnslr]

Wow, what a bending moment that will impart to that hardtop leg.

Please post photos after it bends and ruins your hard top. :hmm

Brian

 

[Sea Shift]

You really think it will bend the hard top supports? There are two welded 2" tubes. I can hang on it and it doesn't even flex and thats 250 lbs. Hmm

 

[ocnslr]

You really think it will bend the hard top supports? There are two welded 2" tubes. I can hang on it and it doesn't even flex and thats 250 lbs. Hmm

Hanging on it applies a compression load to the vertical support struts. They are very strong that way.

The arrangement you propose has a 45* support member and it will transfer a vertical load to the tube it is attached to, and a "bending moment". That bending moment is a load at the top of the tube pulling it outward in the direction of your puller, and an opposite force lower on the tube, where the 45* member attaches, in the opposite direction.

I can't tell you that the tube will bend, but I can say you be applying loads to it that it was not designed for. I certainly wouldn't do it on our boat.

http://www.lainefamily.com/CrabpotPullerProject.htm

http://www.go2marine.com/product/243199F/gunnel-mount-bracket-only.html

http://www.go2marine.com/product/243198F/kickplate-bracket-only.html

Good luck with your project.

Brian

 

[BobP]

I was thinking about this one myself, I like projects, but time we have left over to do projects is never enough!

To the link of the home made setup. Take the square tube SS and take it along the entire hardtop top straight across in line with frame bolted down into the frame in 3 places, and extend out like a boom to proper lenght over side, and add one vertical leg slightly tilted toward the hardtop with the foot on top of the gunnel and weld to the horiz tube, just weld to a flat plate at bottom, bolt down to gunnel top. Then like the link project add the plate at the boom end and hole for pulley,winch, etc The weight on the boom will tend to lift the hardtop which it is not likely, and lateral force shouldn't be that much but if so add a 2nd vertical leg going to an angle forward and land on same gunnel. As i think about it, the (not exactly) A shape vertical frame will be it, connected to the horiz tube, perhaps entirely removable A frame. I don't like alum for this but if so must be very heavy gauge. SS is right choice for me. Square tube works, the larger the tube dimensions the better.

I would make the tube extending past the vertical leg like a tube in a tube with some kind of pin to take apart so it doesn't stick out when not in use.

I'm done. Speedymetals.com etc for supplies, has specs too. And welder.

Me I'd like to convert my Sailfish OEM hardtop plus plastic window/canvas setup into a 3 sided pilot house designed with real glass to see out, open back with extender canvas on rear sides and across stern (like the Judge 27 setup). This vs. $3K or more for new canvas due soon, as well. I'm sure the boat may tend to roll more, glass is heavy, there will be more glass than now. How much more not sure. Need time on drawing board first, or find someone who did it. tired of looking out of plastic, never could ever be the same as glass. I have the glass marine window maker already with stock sizes.

The crab puller is easier. I'd use it for lobster traps here. With block and tackle, no motor.

 

[NOTHING ELSE MATTERS]

John Carroll
Winterville Machine Works
252-756-2130

Call this person. He is the one that made your top.

 

[Sea Shift]

NEM thanks for the contact phone #. I will call that guy next week. As for this weekend, I made it out to the boat and did a little mock up. I think my idea might just work. I took a pair of clamp on mounts and welded a bracket to it. This will allow me to pin the tube to it similar to the deck mount versions I have seen. I am thinking I can bend the support piece and direct the force 90 deg to the lower leg of the rail. That piece is directly back braced to the boat.

 

[Grog]

I'm not sure I'd want to have that hanging off the pipes, they are fairly thin walled. An even 50 pounds of pressure probably wouldn't cause harm but all you would need is a wake to hit at the right time and give you a good roll. The line would go slack and then shock the system which might kink a pipe.

Why not put a davit through the gunnel into the deck?

 

[Sea Shift]

Well, I really don't want to drill more holes int he fiberglass. And to mount the bulsters they make you have to remove the rub rails from the inside which I do not want to do either. Not to mention loss of space, trip haz. I think the design I have will get the puller higher so the traps clear the reail too which will keep my deck hands from having to lean out the side of the boat to pull a trap in. I have had a couple people loose footing and I want to avoid that. I'm looking at what design the commerciall boats around here use and this seems to be similar.
As for the aluminum tube that the frame is made out, it appears to be the same that the pullers are made out of and they stand up to a 90 deg bend in them without bending. I would think that they would be even better with two supports braced in this manner.

 

[Wetcoast Noel]

I'm new to Grady Whites, but I would definatly mount it to the hard top poles, in fact Im going to liberate your idea and weld up some folding arms to do just about the exact thing you mentioned, I may be new to Grady's but not new to boating and I am an aluminum welder with many many years of fabrication experience behind me . Unless your pulling up comercial traps with the 1"thick steel rod across the trap for weight and 2 of them at a time, you should not have any issues with your design. :mrgreen:

 

[Sea Shift]

Well I finally finished it. What do you think? It pulls like a dream no flex or stress as far as I can tell. Keeps the trap high off the rail too so as to not scratch the side. Between this set up and the Ace line hauler we pulled a total of 773 dungeoness this season.

 

[trapper]

http://www.acelinehauler.com/#nogo

Hello Guys, I guess you can't access these south of the border or can you? I have used one of these for about 6 years now for pulling prawn traps. Two traps on a string from 300 to 400 feet. Says it will hoist up to a hundred pounds, haven't been that lucky yet on a prawn haul. Anyway it fits on a scotty down rigger mount. I reinforced the underside of the gunnels with aluminium plate. Have had no issues with movement in the gunnels on my 208 (yea grady for well built). Have had days up here off Vancouver Island where 400 prawns (the daily limit for 2 licences) have been an easy haul. Thought I would give my 2 bits to this topic. Cheers trapper.

 

[Sea Shift]

We surely can and do have those here. Catch'em products sells them in the Northern Bay area and I have used them for years. They work great but I was looking to step up to the next level, which meant a few things to me. One that pulled the trap higher over the rail to eliminate work for the crew, one that gripped a little better, and one that was a little more stable and allowed more room to work. This set up has been working awsome for two seasons now without a problem. Anyone looking to do the same I highly recommend it. I am by no means a mechanic so if I can do it.......

Here is the old Ace I had