How to lighten a tri hull??

[Dwfroghunter]

I spend alot of time in skinny water. I may pick up an old tri hull and restore/convert it to a skiff. I plan to pull the cap and toss it. Replace transome, stringers, floor and add front deck. I would have to redneck engineer gunnels too. It would be a tiller steer when complete. Plywood is heavy, is there a lighter way to do this?

 

[SigSaurP229]

Re: How to lighten a tri hull??

that hull gets alot of support from the cap I would seriously consider revising, your plan of action.

 

[Dwfroghunter]

Re: How to lighten a tri hull??

The new decks would replace all the support I removed.

 

[Scott Danforth]

Re: How to lighten a tri hull??

So you plan on removing 500# to replace with 500#?

Why not just buy a skiff. It will save you a fortune.

 

[Woodonglass]

Re: How to lighten a tri hull??

Not to mention that a Tri-Hull sits fairly High in the water. I'd think you'd want to sit a lot lower for "Skinny Water". I too don't think a Tri-Hull conversion is a good idea for this application. But Hey I been wrong a lot of times! If you wanna give it a go and put your time and money into the project, who am I to discourage you!!! It's a New Year and Everyone is full of New HOPE, Go For IT if thats what you want to do!!!!!

 

[Dwfroghunter]

Re: How to lighten a tri hull??

If I do it this will be a year plus long project. A few dollers here and there. If I had the money to buy a skiff then I would not be looking at a free tri hull. I would like to remove 500lbs and replace it with something lighter. Which is the point of this thread. (That I still have no answers to) as far as high sides go my buddies current rig has 28" sides. I want a boat with high sides.

 

[SigSaurP229]

Re: How to lighten a tri hull??

I guess aluminum would be lighter and stronger, but I am not sure how you could successfully bond it to the fiberglass and gelcoat. Major overhauls like you are talking aren't just a few dollars here and a few dollars there, don't believe me see my thread below.

I am sure it can be done, and I would think that aluminum would be the "lighter stronger" way to do it, but I just don't think it can be successfully and strongly done anyway other than plywood and fiberglass.

But if you decide to try the whole forum would be here to help

 

[jbcurt00]

Re: How to lighten a tri hull??

What makes up the 500lbs you're removing? Speculation about the weight of the cap, dry foam, and interior component weight?

Swapping a 50+hp remote steer OB w/ a tiller steer 35hp will save some weight, how much depends on what you remove & what you replace it w/, so not sure anyone could give you accurate guess-timates on the weight savings.

If you want to grab a tri-hull & convert it, let us know what boat you end up w/ but removing the cap & interior will require some kind of structure be put back to support the hull sides. Come up w/ a plan & perhaps we can help find some weight savings.

My only suggestion would be to pick a wide flat style tri-hull, rather then an air-slot style hull.

 

[GA_Boater]

Re: How to lighten a tri hull??

Now we know you're looking for a free boat. Make sure you can get it registered or every dime and minute of time will be wasted.

 

[Woodonglass]

Re: How to lighten a tri hull??

What Kind of Power are you envisoning?

 

[Dwfroghunter]

Re: How to lighten a tri hull??

The boat is my fist power boat. It has been forgot about for the last 12 years at my dads. I checked and its still titled under my name. It is flat and wide. 16' long and 63" wide. Max hp rating on it is 85hp. I'm thinking more along the lines of a 40 horse. Sides on it are in the 20" range. I don't rember what brand or year it is.

My buddy welds aluminum. If I built a welded frame work for a flush front deck, would mechanical fasteners(bolts) work?

 

[coolbri70]

Re: How to lighten a tri hull??

you could use plascore in place of the plywood, but its pricey

 

[jbcurt00]

Re: How to lighten a tri hull??

A forgotten & neglected boat will require some work if it's been sitting for 12+yrs. It will likely require quite a bit of work actually..

Post some pix of it

Perhaps a modified cap would work better then removing it completely. If only as a perimeter cap.

Depending on the condition of the hull's lip, and where you want to thru bolt an aluminum platform support, it may not be a wise choice to use aluminum & bolts.

 

[Woodonglass]

Re: How to lighten a tri hull??

The cap is prolly riveted or Screwed to the hull. I see no reason why you could not fabricate an aluminum rail to conform to the shape of the hull and rivet it in place and then attach the plywood deck to the aluminum rail. In fact I think it would be quite effective.

 

[Dwfroghunter]

Re: How to lighten a tri hull??

I will get some pics this weekend. I found a local place that sells polyester resin. Will this be a good choice for stringer/transom replacement?

Can you please explain why the aluminum to fiberglass is bad.

 

[Woodonglass]

Re: How to lighten a tri hull??

Poly Resin is what the boat is made from so Yeah it'll be good but... certain kinds are better than others. What place are you referring to that sells it? Poly does not stick to aluminum so trying to get aluminum to bond to fiberglass is kinda like mixing oil and water... just not gunna happen.

 

[NSBCraig]

Re: How to lighten a tri hull??

I'd cut the cap and use the outer part still. Losing the windshield, side consoles, bow seats, bench seats will shed a lot of weight. of course what weight you end up at when your done? Start rippin it apart. Get all the junk out and go for it. Use 1708 glass and poly resin. I think there is a simular thread on here.

 

[Dwfroghunter]

Re: How to lighten a tri hull??

I think the cap is screwed on. Is there a chance of the bolts causing the fiberglass to break while it flexes on the water?

 

[Woodonglass]

Re: How to lighten a tri hull??

Yep, it could but, if you put a strip of 1708 over the top edge of the hull and then use rivets or screws to attach the aluminum (you don't need bolts) then I doubt it would flex and crack once the plywood deck is installed.

 

[SigSaurP229]

Re: How to lighten a tri hull??

That was my concern was the flex.