Delaminated Hulls

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Repairing Delaminated Hulls - Injection

By Tami Shelton 

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You will need to inject epoxy resin in the hull sandwich layers. 

Obtain large horse syringe from your friendly veterinarian or supply house. Then get a gerbil (whoops, sorry, wrong advice list ;-) 

Drill 2mm holes (or s/size as syringe nozzle) in 3 inch triangular pitch pattern (zig-zag) thru gelcoat layer and foam layer but be careful and stop the drill before the glasscloth/resin layer. 

Bend a small piece of coathanger wire about 1 inch long into an L shape (right angle). Insert in drill like a bit, and slip into the holes you've drilled to scour out the foam in the immediate vicinity of the hole. 

(This is so resin can spread in all directions once injected) 

Inject resin in the first hole until it comes out the next, and tape off the first hole, and continue down the hull until all holes are injected with resin. Because of the large volume of resin, don't mix it too "hot" (with a lot of hardener). The catalytic action of the heat can mess things up with a large mass of resin. Once it starts to react, keep an eye on it and cool the resin off if need be. 

If you can access the bad spot, it would be best to try and make sure the inside glass layer is pressed up against the foam tightly, but generally this is not possible. 

If the hull is really bad, delaminating all over, it really works great to drill 6mm holes along the top every 2 ft. (600mm) and inject marine foam about 2lb/cuft. (he thinks) (figure that out yourself) density in the whole hull. This stiffens the hull up good and only adds about 15 lb. or so. Works a lot better than you'd think, but it's a last-ditch although easy to do. An experienced hand should inject the foam, just enough such that it foams up and out of the holes. Too much foam or holes too far apart will cause bubbles and buckles in the hulls sides. 

It is also comforting to know when sailing a piece of junk such as this that the foam will be there when all else fails. But then, we don't have sharks. Although a couple of miles through the marsh would bring Arnold to tears. 

Remember there's a block of foam in the Hobie 16 between the pylons which floats the hull but won't support the mast; a flooded hull will heel to that side and capsize. 

If you have questions, write to David in care of me, Tami 

Tami Shelton
trs4389@usl.edu

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