How to lighten a tri hull??

[Dwfroghunter]

Re: How to lighten a tri hull??

This is something else that confuses me(got lots if that!).

If fiberglass is waterproof and all wood in the boat is glassed in, then why must it be marine grade wood?

If done correctly the wood should never see water correct?

 

[ondarvr]

Re: How to lighten a tri hull??

If you are looking for a light, low cost boat for skinny water, get an aluminum jon boat, you will spend far less money than trying to fix up an old glass hull, it will also perform much better. You have already listed a few hundred $$ worth of stuff to buy to fix the glass hull, and much more will be needed, not to mention the labor involved. You will also be able to use a smaller motor which again will cost less money.

Free up front doesn't mean a low cost final product.

 

[Dwfroghunter]

Re: How to lighten a tri hull??

The old saying "there is nothing more expensive than a free boat" comes to mind. I currently run a 1648 jon boat. It does everything I want. Problem with it is my 3 boys now fish with me. They are 5-10 and quite a load on a 1648. I have looked for over a year now for a bigger Tin boat that will hold 5(including momma) that I can afford. I have yet to come even close. My buddy runs a 1660 Tin boat with 28" sides and it handles a load well.

That's the reasoning behind looking at this tri hull. 16'x63" with 20" sides. Should do well in calm water.

 

[Scott Danforth]

Re: How to lighten a tri hull??

regarding resin, make sure it is layup resin (not waxed) resin from Bondo or Elmers that you get at home depot is waxed and required grinding between layers.

just for reference. the plywood and fiberglass materials to repair my motor mounts, two 6' sections of stringer, a bulkhead and a transom cost me in the neighborhood of $1000 that did not include the Protective Equipment needed when working with fiberglass. that was another $150

I used well over 10 gallons of resin.

you can buy a tin boat for $1150 and go fishing today.

 

[Georgesalmon]

Re: How to lighten a tri hull??

Look up ITW Plexus. I've used their adhesives at several manufacturers to bond fiberglass to aluminum even on Yachts over 120'. I've also used it to bond composite stringers to hulls on offshore fishing boats in the 35'-65' range, that's right, no glass. If you ever fly be advised that a lot of the airframe and skin are also bonded together with the same type of adhesives. It is stronger than the interlaminar sheer strength of fiberglass composites including epoxies. Stuff is expensive though and it doesn't work on wood.

 

[gddavid]

Re: How to lighten a tri hull??

I understand your motivation as a tri-hull would be stable to stand up in and cast from and there are construction methods to do it but they are expensive. Foam or balsa wood cored decks laminated with epoxy resin fiberglass using a vacuum bag technique will yield a very high strength result but the materials and tools required are expensive and not easy for a novice. Light, strong and cheap - pick two but you can't have all three (unless you get an aluminum skiff). Unfortunately many older used aluminum boats run relatively narrow for their size and not as stable to stand up at the gunnel height to cast from so you really want a wide flat bottom skiff to perform best and they are going to be newer and pricer.

Fabricating an aluminum deck to your tri-hull would be possible but difficult would likely cost twice in materials than what you could find a nice newer aluminum boat for. Alot of your expense will be in your motor anyway.

edit - I assumed you were flats fishing but judging by your handle you are likely frog gigging, which I don't know anything about but would imagine that you want to stand up for as well.

 

[jbcurt00]

Re: How to lighten a tri hull??

This is something else that confuses me(got lots if that!).

If fiberglass is waterproof and all wood in the boat is glassed in, then why must it be marine grade wood?

If done correctly the wood should never see water correct?

It's not waterPROOF. So no, not correct. On a very minute scale it's porous. And like many products, if water is splashed on it, drains off & is allowed to dry, it will likely weather the water exposure quite well. When they are left exposed to (or submerged in) water long term thru several hot/cold or freeze thaw cycles many extremely water resistant materials break down. Flotation foam & wood encased in fiberglass suffer greatly when exposed to the elements & neglected.

Although in a perfect world we would all use marine plywood on our rebuilds, it's expensive, it's hard to find in some locations (I can't even get a lumber place to order it for me here) many of us choose to use a product that is as close as we can get: Auraco, MDO or ACX plywood. They are all made w/ quality lumber, relatively void free on both the face & more importantly on the interior laminates, readily available in most places AND are made w/ exterior glue.

You should assume at some point water WILL penetrate the fiberglass. When it does, you want to have done everything you can to prevent the wood from completely disintegrating QUICKLY. It's a heck of a lot of work doing what we do rebuilding fiberglass boats, you don't want to have to redo it again anytime soon. For $10-15/sheet more money you can use substantial products that will resist water intrusion.

Storing your boat correctly, covered, bow high & w/ the drain plug removed once your done w/ your build will help even more.

 

[Woodonglass]

Re: How to lighten a tri hull??

I'm gunna kinda repeat Post #5. This IS a DIY'er forum. You ARE a DIY'er. Most of the Regulars here on the forum are concerned a LOT about safety and trying to make certain that newb's are made aware of the Cost's involved in repairs and also using the correct materials to ensure that their builds are done correctly and safely. Me Too!!! As long as you are aware of the Costs and the safety factors and you want to pursue the project then don't let anyone or anything discourage you from it. You may have resources and materials at your disposal that none of us are aware of that will make it totally worth the effort. I've seen a lot of Crazy things in my life that I thought "What was that guy Thinking?" but... They worked for him... It's your life and your family. If you can make it work and keep em safe then "Go for it!!!!" That's just the take of one