Bunks setup ?

cloumar

Petty Officer 1st Class
Joined
Aug 12, 2002
Messages
305
Hi folks,<br /><br />I have an aluminium 16.5 feet fishing boat with a 75 HP outboard - question is how far my boat could sits out of the end of the bunks, for now the transom sits about 3 inches behind the end of the bunks.<br /><br />Thnaks <br /><br />Smoky ;)
 

jtexas

Fleet Admiral
Joined
Oct 13, 2003
Messages
8,646
Re: Bunks setup ?

You need to get that transom up on those bunks - a tiny bit of distortion there could make a big difference in performance.
 

jeff_nicholas

Petty Officer 2nd Class
Joined
Aug 2, 2002
Messages
174
Re: Bunks setup ?

Here's a snippet regarding aluminum boats on bunk trailers:<br /><br />Bunk trailers typically have long boards (called bunks) that form a cradle for the boat. They usually are carpeted to prevent marring of the boat finish and to provide a surface for the boat to slide on when launching or retrieving. Some bunks may use a surface different that carpet. Whatever surface the bunks must be undamaged to prevent damage to a boat. <br /><br />Bunks must be mounted flat side to the boat not as rails. They should be angled to lay flat against the hull. The maximum amount of surface in contact with the hull is what is necessary. The widest bunks that will fit consistently between the strakes are best. The strakes are the long pressed aluminum ridges that run from front to back along the bottom of a Duroboat. <br /><br />When the boat is on the trailer the strakes must not be resting on the bunks. Bunks must be between the strakes. Strakes on the bunk concentrate weight on too narrow a surface. <br /><br /> The bunks should extend beyond the rear of the boat. Two inches is desirable. Under no circumstances should bunks terminate short of the transom. If they do they will create an edge that will act as a pressure point on the hull. The bouncing motor and transom will work on this point and cracks may develop in a hull. <br /><br />Full article at:<br /> http://www.duroboat.com/article002.asp
 

breton26

Seaman
Joined
Apr 3, 2005
Messages
51
Re: Bunks setup ?

Should this be the same for fiberglass boats??? What should I do for this mess?
DSC00044.jpg
 

craze1cars

Lieutenant Commander
Joined
Dec 26, 2004
Messages
1,822
Re: Bunks setup ?

Originally posted by breton26:<br /> Should this be the same for fiberglass boats??? What should I do for this mess?
DSC00044.jpg
Yep, no diff. Your easy solution there is to replace the bunks with longer ones that stick out an inch or two beyond the transom. Another alternative is to move the winch stand forward, but that might get your tongue weight too heavy.<br /><br />Incidentally, a motor and steering system would be helpful in maintaining control of your "mess." :D
 

breton26

Seaman
Joined
Apr 3, 2005
Messages
51
Re: Bunks setup ?

I am in the process of redoing the floor and buffing the gelcoat so everything is stripped off the boat right now. But with the motor on it, the tongue is still real light. I think I need to move the winch forward, lengthen the bunks and turn them over so the wide side is against the boat. Right now the narrow side is against the boat. I also need to strip, prep, paint, bearings, tires, wheels, etc, etc. The job is never done.<br />Also, i noticed that most of the weight is on the keel rollers.
 

craze1cars

Lieutenant Commander
Joined
Dec 26, 2004
Messages
1,822
Re: Bunks setup ?

Originally posted by breton26:<br /> <br />Also, i noticed that most of the weight is on the keel rollers.
This really is not a problem for your boat. Most of the weight should be on the keel...strongest part of your hull. The bunks are just for stabilizing and preventing it from tipping over, they won't support much weight anyway.<br /><br />Frankly, I didn't notice you had keel rollers until you mentioned it, this makes the bunks much less critical. So I wouldn't worry about having them long enough to support the transom, but as long as you're redoing them for other reasons, it certainly can't hurt to lengthen them some. More weight distribution is always better than less. Have fun with the never-ending project!
 

jtexas

Fleet Admiral
Joined
Oct 13, 2003
Messages
8,646
Re: Bunks setup ?

Yes, do have bunk support for the transom. Less critical than with aluminum? fair statement, but long-term, with the motor hanging there you can develop stress fractures.
 

breton26

Seaman
Joined
Apr 3, 2005
Messages
51
Re: Bunks setup ?

Thanks guys, I'll definately fix that problem as soon as I put the boat back together.
 

kgorey

Cadet
Joined
Jan 13, 2005
Messages
8
Re: Bunks setup ?

Hello all. I have the same problem with my boat/trailer. I just bought it this winter and noticed this weekend that my bunks are about 1" short of the transom. I had noticed before that the winch post has already been moved about 3"-4" forward and I am hesitant to move it more. My tongue weight already seems heavy. The trailer is made for the boat which is a 17.5 ft. aluminum skeeter with a 75 mercury. Any suggestions?
 

imported_Curmudgeon

Chief Petty Officer
Joined
Sep 29, 2004
Messages
496
Re: Bunks setup ?

That inch is much less important than correct tongue weight. A known weight for the rig and the tongue would be soooo much better than My tongue weight already seems heavy.
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: Bunks setup ?

Originally posted by kegman:<br /> The trailer is made for the boat
Don't beleive it. My first boat's trailer was "made for it" too. After I moved the winch forward it was still a couple of inches short, and I was definitely heavy on the tongue. Dealers and builders can keep their costs down by selling a combo with a trailer one size too small.<br /><br />The only time that this is good is if you have a severe porpoising problem. Wait long enough and the developing hook in the hull may help alleviate the porpoising . . . :eek:
 

craze1cars

Lieutenant Commander
Joined
Dec 26, 2004
Messages
1,822
Re: Bunks setup ?

This post has got me thinking. What about full roller trailers? Like your typical EZ loader with nothing but rollers all over the place. It seems to me that there's little to no support directly under the transom on most of those. Not sure if that's correct or not, just an observation.
 

kgorey

Cadet
Joined
Jan 13, 2005
Messages
8
Re: Bunks setup ?

"A known weight for the rig and the tongue would be soooo much better than My tongue weight already seems heavy."<br /><br />Agreed, I should get it on a scale but I believe the package weight is between 2100-2200 lbs. If that's true, I would guess my tongue weight should be between 110-150 lbs. If I can get away with pushing that up to maybe 200 lbs., I might consider moving the boat forward to get it completely on the bunks. I really don't want to re-shape the hull.<br /><br />As far as full rollers go, a buddy of mine just bought a new trailer that way but he doesn't have an outboard. I imagine it depends on the boat style.
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: Bunks setup ?

Oh crazed one,<br /><br />Good point. Somebody has got to know something. Anybody? Bueller?
 
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