SWISS CHEESE TUB

[Niklas Edlund]

A few years back I made some laminated (21 sized) wood tub sides in an effort to make them lighter... Like 0.8 mm aero birch ply for outside and 1 mm aero birch inside and max cut-out's (not only drilled out holes) 3 or 4 mm balsa or obechi as core, laminated together with as thin a layer as possible with different versions of epoxy... Everything ended up heavier then the stock marine spec gaboon/okume 6 mm (1/4) plywood. I might remember wrongly though but I think the 6 mm gaboon one is even lighter then 1/8 (3 mm) aero birch plywood... But a good laminate can defenetly be more ridgid then stock gaboon marine plyuwood though. If aiming for a stronger (and lighter) I would go directly to all carbon with additional divinycell (or airex) as core material where needed...

 

[Buckshot]

There is a photo in someones gallery of an outrigger that ran at the World Champs sometime ago that had a tub with "trellis" style sides covered in the stuff that is used on R/C airplane wings.

It looked pretty cool but.......

I'll look in the A.M. to see if I can find the photo.

 

[dwilfong]

I made some tub sides out of the luan today and was the lithest by far 170g with no holes. The 1/4" was 250g and 200g with the holes. Will pick up some Okoume BS1088 5 ply tomorrow and see what happens.

I have a feeling the Okoume will be the winner.

Next I will use the finish epoxy and bond some 1K CF to a drilled out tub side on one side. The 1K CF is very thin and should not hold much epoxy.

Will coat the side and put the CF on. Then coat the CF and weight it down on a piece of wax paper to squeeze out the epoxy.

The amount of epoxy will be minimal to say the least.

I am trying to come up with a simple system that any one can do with out special equipment or building skills and at a minimal cost.

David

 

[Buckshot]

There is a photo in someones gallery of an outrigger that ran at the World Champs sometime ago that had a tub with "trellis" style sides covered in the stuff that is used on R/C airplane wings.

It looked pretty cool but.......

I'll look in the A.M. to see if I can find the photo.

This is the boat I'm referring to. It’s from Niklas Edlund's 2008 World Champs Gallery.

Makes me think of a Ducati.

Buck

 

[dwilfong]

I will definitely try that.

It is way cool.

David

 

[Wes James]

Next I will use the finish epoxy and bond some 1K CF to a drilled out tub side on one side. The 1K CF is very thin and should not hold much epoxy.

Will coat the side and put the CF on. Then coat the CF and weight it down on a piece of wax paper to squeeze out the epoxy.

The amount of epoxy will be minimal to say the least.

I am trying to come up with a simple system that any one can do with out special equipment or building skills and at a minimal cost.

David

David-

I think you'll find that when you compress the laminate, what will happen is the excess epoxy will squeeze out into the holes, and you won't get rid of as much excess as you might hope to...

Good luck with your project- interesting concepts.

Wes

 

[dwilfong]

Next I will use the finish epoxy and bond some 1K CF to a drilled out tub side on one side. The 1K CF is very thin and should not hold much epoxy.

Will coat the side and put the CF on. Then coat the CF and weight it down on a piece of wax paper to squeeze out the epoxy.

The amount of epoxy will be minimal to say the least.

I am trying to come up with a simple system that any one can do with out special equipment or building skills and at a minimal cost.

David

David-

I think you'll find that when you compress the laminate, what will happen is the excess epoxy will squeeze out into the holes, and you won't get rid of as much excess as you might hope to...

Good luck with your project- interesting concepts.

Wes

Wes

The finish epoxy takes along time to kick. The lamination will only be on the out side. I am planing on doing the lamination to the tub sides before I build the tub. The hole size is 3/8" and will be easy to remove the epoxy before it kicks off with a small brush. This should keep the epoxy to a minimum.

Found a cheep source for Carbon cloth.

http://www.solarcomposites.com/composites/compositecarbon.html

As for the Okoume that is a different story. The local distributer wants $130 for a 4x8 sheet and will only sell a hole sheet. Still looking for a good source for it .

Will let every one know the results.

David

 

[dwilfong]

I got some 2.4oz C/F and did a test piece 1.5"x3" this would be equal to 3" of my tub side. The control piece was 9g, with finish epoxy on one side 10g.

The same size piece with holes was 7g, with carbon fiber and epoxy 9g.

The wax paper worked like a charm the finish is perfect and the paper fell right off. Used paper cloth to soak up excess epoxy in the holes.

So there you go it worked.

Going to play connect the dots with the next one and create the trellis work next. This should save much more than gust the holes.

David

 

[namba969]

I wonder if laminating carbon to some balsa would be strong and light enough?? I've seen 1/32ply and balsa sandwich before... plenty light and strong! So i would think carbon balsa would be good too. Just thinking here...

Andrew Grenier

 

[dwilfong]

I wonder if laminating carbon to some balsa would be strong and light enough?? I've seen 1/32ply and balsa sandwich before... plenty light and strong! So i would think carbon balsa would be good too. Just thinking here...

Andrew Grenier

I have some Okoume 6mm on the way. will see how lite it is. I think the plywood would give the best strength to weight ratio.

I started to practice cut more out of the tub sides to form the trellis. There will not be much left when I am done. Think the 5ply should give it the strength needed more than the balsa.

With the balsa would have to cover both sides. The epoxy weighs a lot . Trying to use as little epoxy as possible. This will be the trick to weight savings.

Even with foam core you have to cover both sides and use two layers of cloth. The cloth holds epoxy and that is where the weight is. By covering one side using plywood you can cut down on the epoxy used.

It is also MUCH cheaper than the foam. Can try diffrent cut outs with the Luan an not break the bank.

The finish epoxy works great thin as water and slow to kick. Plenty of time to control the amount with a paper cloth in the voids.

David

 

[Terry Keeley]

I got some 2.4oz C/F and did a test piece 1.5"x3" this would be equal to 3" of my tub side. The control piece was 9g, with finish epoxy on one side 10g.

The same size piece with holes was 7g, with carbon fiber and epoxy 9g.

The wax paper worked like a charm the finish is perfect and the paper fell right off. Used paper cloth to soak up excess epoxy in the holes.

So there you go it worked.

Going to play connect the dots with the next one and create the trellis work next. This should save much more than gust the holes.

David

Ahhh, you discover the golden black cloth glasshopper, you learn well...

 

[dwilfong]

I got some 2.4oz C/F and did a test piece 1.5"x3" this would be equal to 3" of my tub side. The control piece was 9g, with finish epoxy on one side 10g.

The same size piece with holes was 7g, with carbon fiber and epoxy 9g.

The wax paper worked like a charm the finish is perfect and the paper fell right off. Used paper cloth to soak up excess epoxy in the holes.

So there you go it worked.

Going to play connect the dots with the next one and create the trellis work next. This should save much more than gust the holes.

David

Ahhh, you discover the golden black cloth glasshopper, you learn well...

Yes I think I will be addicted to this stuff.

 

[Wes James]

I got some 2.4oz C/F and did a test piece 1.5"x3" this would be equal to 3" of my tub side. The control piece was 9g, with finish epoxy on one side 10g.

The same size piece with holes was 7g, with carbon fiber and epoxy 9g.

The wax paper worked like a charm the finish is perfect and the paper fell right off. Used paper cloth to soak up excess epoxy in the holes.

So there you go it worked.

Going to play connect the dots with the next one and create the trellis work next. This should save much more than gust the holes.

David

Ahhh, you discover the golden black cloth glasshopper, you learn well...

Yes I think I will be addicted to this stuff.

Very cool, David- nice to see you're finding success in your processes!

Wes

 

[dwilfong]

Well here it is. Can you say cheese.

This is the test piece made out of Luan ply. The original is 85g and the one with the trellis work is 50g.

The final ones will be made out of Okoume ply. Finley got some. Real nice and light and marine grade. Even lighter than the Luan.

Took some time to lay out the trellis work and practice cutting it out with a Rotozip bit in a Dremel.

David

 

[dwilfong]

Here is the finish piece. Savings over one with out holes 16g. Over 1oz. in total weight to the boat.

David

 

[dwilfong]

Well apples to apples saved 1/4 lbs.

 

[bzubee]

We're using some honeycomb aircraft material and so far it has reduced the weight of a 45 rigger made from plywood down by 1 POUND using the honeycomb material instead of plywood. Plus it is much stronger and stiffer.

 

[dwilfong]

We're using some honeycomb aircraft material and so far it has reduced the weight of a 45 rigger made from plywood down by 1 POUND using the honeycomb material instead of plywood. Plus it is much stronger and stiffer.

I Have a mold coming for a 45 boat and will try a lay up in it with the honeycomb.

David

 

[Terry Keeley]

Light is Right!

Don't let anyone tell you different!

 

[Buckshot]

There is nothing lighter than a hole. B)