convert soft bottom inflatable to hard bottom dinghy

Hello,
I have an old soft bottom zodiac with a rough bottom. The rubberized coating is peeling off exposing the mesh. I realize one can repair these with rubberized paint but it is relatively expensive and seems relatively fragile.

I was wondering if it would be possible to convert the dinghy to hard bottom by say, taking a piece of plywood, cutting it to form, and laying down fiberglass mat so that it lays nicely over the middle part of the innertubes (beyond the seams) and then epoxy (perhaps with west-system Six10) it to the tubes (I think they are PVC, but could be hypalon)?

Or, any other ideas to repair the bottom?

Thanks!

 

If it is you opinion that a can of rubberized paint is expensive, forget about turning your old Zodiac into a rib. Chances of success are slim, especially bonding the rigid bottom to old Hypalon.

 

If you put anything hard into this boat it will chafe with the rubber and cut it ....

 

I thought of this from a slightly different perspective. I just bought a flex bottom inflatable and used it once. Don't like it. Thought of putting a flexible piece of plastic inside like xluke suggests. Would be nice if one could find a piece of plastic whereas the edges are or could be made more flexible than the rest. One could sand the edges smooth and rounded. One could use a piece of plastic like a Colman canoe but the edge would be most of the time in the same place and wear out the bottom at that point. The white packing foam around the edges may help. I need one of things to work as it's the only dinghy light enough to be easily pulled up on the cabin top.

 

Why not just build a new rib floats and all? Ever seen the foam pool toys, you know the long round ones ? (don't know what they are called) . Well if you could aquire the right diameter of these things from the manufacturer I think you could make the ultimate rib. super light, waterproof, no punctures to worry about. Probably would want to locate a good supplier if heavy duty shrink wrap as an outer casing material. Could even have an inner air chamber to firm it all up when done, deeply centered in the foam of coarse.

 

I think its what you put around the edge of the ply or plastic thats the trick.... say a length of 1 in dia plastic water pipe split down the side ..thats to make the edge round and then what in australia they call a Poole Noodle ..split the same way if it was nice and tight fit ...blow up after fitted should work easy ... thanks to easy rider for the idea

 

A Pool Noodle, exactly.
If you could locate a source on, say, 18-24 inch rounds of this stuff I think it would be superior upgrade from Hypalon. That pool noodle foam is super light, tough, and buoyant. And how simple would it be compared to the construction of a Hypalon tube?

 

I was thinking of fitting this inside the boat as a new floor ..maybe glue the old one to it or make a sandwitch ..on sheet ply inside one outside ....

 

I think you guys are taking a simple idea and making it really complicated to end with a product of less quality. There are soft inflatables, ribs, and hard hulls. Each has good and bad points. Making tubes is fairly straightforward. The trick is designing the panels so they will fit properly. The same can be said for the panels on a hard hull.

 

but the guy did not want to make a rib he wanted to change it to a hard floor ...what can be simpler than some 1/4 ply and a pool noodle......

 

The Zodiac cadet roll up has nylon floor, they are crap the bottom falls out because you cant stick nothing to nylon. I have Just sold a brand new one with the floor hanging out.

I have spent my life trying to make stuff out of bits of this and that. I give up. After a few tubes of sika flex and fugly dinghy that last an hour take my advice and buy a new one or a used one theres more to life.

 

Fosty Rules

 

I couldn't agree more, buy the right boat the first time.

-Tom

 

- but he already has this boat and by the sound of it has had it some time.

I agree there would be a concern over the potential for abrasion with a ply floor. My approach would be, first take a look at a RIB boat and see how the problem is dealt with there. I would certainly consider using the idea of pool noodles between the ply edge and the air bags to prevent rubbing.

However if noodles are simply split and fitted on the ply edge that will leave a gap between the ply and the fabric of a few inches. Maybe half-round noodles could be glued to the top of the ply around the edge. Alternatively the noodles could be edge-fitted as suggested previously but some thinner (or half round) noodles added fore-and-aft under the floor to support the fabric.

Any ideas on ply thickness? Based on typical wood boat practice I would suggest about 1% of the beam, but there may be reasons for something else that I don't know about, never having owned a zodiac.

 

My RIB had a scalloped edge conforming to the tube shape. Tube just rested naturally in it slot. and the pool noodle needs to be one super oversized one with a couple v notches at the bow to make the curve. Maybe 18" tubes. maybe a 6-8" center hollow for an air compression tube for some ride control options.
Definitely don't need any sharp edges of any sort.