Any information on building your own RIB

[Mr.Boat]

Hi Everyone,

I'm planning to build a RIB myself. The idea is a 7.5 mtr. boat with a plywood/glass/epoxy hull reinforced with aramid (outside) and Carbon (stringers inside). Probably Hypalon tubes.

This way I think I can build a lighter, tougher boat.

Anyone knows where to buy plans for a RIB? I looked at gemini in the UK but does anyone has experience with this company?

Thanks in advance.

Frank

[Nos4r2]

Originally Posted by Mr.Boat

Hi Everyone,

I'm planning to build a RIB myself. The idea is a 7.5 mtr. boat with a plywood/glass/epoxy hull reinforced with aramid (outside) and Carbon (stringers inside). Probably Hypalon tubes.

This way I think I can build a lighter, tougher boat.

Anyone knows where to buy plans for a RIB? I looked at gemini in the UK but does anyone has experience with this company?

Thanks in advance.

Frank

There seems to be very little good feedback on Gemini Industries.

http://rib.net/forum/showthread.php?...ini+industries

[Mr.Boat]

Thanks. Strange story. Anyone knows of plans (other than gemini) available for RIB hulls? I know it sounds ambitious bit it's something I really want to do.

Are there others who have built their own boat?

All sugestions are apreciated.

[Chris]

Originally Posted by Mr.Boat

Thanks. Strange story. Anyone knows of plans (other than gemini) available for RIB hulls? I know it sounds ambitious bit it's something I really want to do.

Are there others who have built their own boat?

All sugestions are apreciated.

In order to build a hull would you not need to carve a plug first to then create a mould? SOunds like a lot of work for just one boat.

Why not look for a manufacturer that can sell you the bare hull so you can then fit the boat out to your spec.

Osprey and Shakespeare (I think) will do this and I think Humber will too.

[martini]

Adam Younger on here designs ribs.

website here

[Polwart]

Originally Posted by Chris

In order to build a hull would you not need to carve a plug first to then create a mould?

No he is proposing making it from ply wood, the same way that home build sailing dinghies (and I assume powerboats) were built in the 60's and 70's (and still are today to a much smaller extent). Alternatively you could build one from Aluminium - but thats not normal DIY skills.

An alternative might be to pick up some molds (they come up on ebay from time to time, and I am sure there will be a few rib co's going to the wall in the next year or two) and lay up the hull in GRP.

[Mr.Boat]

Originally Posted by Chris

In order to build a hull would you not need to carve a plug first to then create a mould? SOunds like a lot of work for just one boat.

Why not look for a manufacturer that can sell you the bare hull so you can then fit the boat out to your spec.

Osprey and Shakespeare (I think) will do this and I think Humber will too.

The kind of hull I want to build is stitch&glue. For the core I use marine plywood. Then the bottom is layed up wit 2 x glass, 1 x aramide and again 2 x glass. Inside 2 x glass with carbon stringers. Everything is epoxy, not polyester. It's build on a jig.

It's a proven method which makes lighter, stronger hulls (than GRP that is) which would allow a smaller engine.

I know I can buy a hull but I like to build one myself. Concerning tubing I think I'm going for a professional company in the Netherlands. Only thing left is the plans for the hull...

[jwalker]

Originally Posted by Mr.Boat

... I know it sounds ambitious bit it's something I really want to do.

Are there others who have built their own boat? ..

I was about to do it for my last boat but time was against me. I still wish I had been able to go ahead with it so I understand your enthusiasm.

If you are sure you only will make one then the plug>mould>build process will be unnecessary because you could make a hull in about the same time as it would take you to make a plug.

My method was going to be formers covered in strips of spruce of a reasonable thickness to allow carving for the formation of compound curves. Overlaid with fibreglass laminate and also laminated inside to form a sandwich construction. The longitudinal stiffening was to be two longitudinals from transom to bow and 50mm thick, either Mahogany or Douglas Fir. Some parts of the spruce would be removed to ensure the longitudinals were attached to the outer of the hull. 25mm marine ply deck bonded and screwed to the longitudinals and laminated to the hull sides and over onto the tube flanges.

You can have that for free.

Good luck.

Edit: Your post arrived while I was typing this one so here's a further comment. If you use stitched ply you limit yourself to a hull which can only be formed from development of flat panels. Personally, I feel there are worthwhile hull characteristics which can only be produced using compound curves.

[Mr.Boat]

Originally Posted by jwalker

I was about to do it for my last boat but time was against me. I still wish I had been able to go ahead with it so I understand your enthusiasm.

If you are sure you only will make one then the plug>mould>build process will be unnecessary because you could make a hull in about the same time as it would take you to make a plug.

My method was going to be formers covered in strips of spruce of a reasonable thickness to allow carving for the formation of compound curves. Overlaid with fibreglass laminate and also laminated inside to form a sandwich construction. The longitudinal stiffening was to be two longitudinals from transom to bow and 50mm thick, either Mahogany or Douglas Fir. Some parts of the spruce would be removed to ensure the longitudinals were attached to the outer of the hull. 25mm marine ply deck bonded and screwed to the longitudinals and laminated to the hull sides and over onto the tube flanges.

You can have that for free.

Good luck.

Edit: Your post arrived while I was typing this one so here's a further comment. If you use stitched ply you limit yourself to a hull which can only be formed from development of flat panels. Personally, I feel there are worthwhile hull characteristics which can only be produced using compound curves.

Thanks for your suggestions. Do you refer to stepped hulls?

[jwalker]

Originally Posted by Mr.Boat

Thanks for your suggestions. Do you refer to stepped hulls?

Nope. Sharp corners are stress raisers. Curved surfaces can be used for adjusting lift, shedding water and guiding water.