Cracked hull

[fishstu]

I have found a 6 in wide crack on the outside of my SC20MA hull. The crack runs outward from just off the center spar (port side) approx 3 ½ ft forward of transom. Tapping using a hammer, forward of the crack sounded very solid and stiff, abruptly right at the crack and farther back the hull sounded different and not so solid. To me it looks like a “hinge” stress crack caused by an abrupt change in hull stiffness in the wrong place.
My next step is to take off the seat post fitting and look in.
I have a feeling that I am going to have to open up the deck to properly fix this.

Has anybody else seen a similar crack, have ideas of the cause suggestions for the fix?, Also how to open up a good deck to do a similar fix

All advice is extremely appreciated
Fishstu

Many thanks Bryan

http://i56.photobucket.com/albums/g1...ll002Small.jpg

http://i56.photobucket.com/albums/g1...ll005Small.jpg

[Bryan A.]

Read this

http://www.classicseacraft.com/forum...b=5&o=&fpart=1

If you have any more questions about pics, post them here and we'll help. Once you try it you'll get the hang of it and it will help with the diagnosis.

[fishstu]

After talking to Ron at Seacraft and more investigation it turns out the crack is a poor hull repair failing. Ron suggested opening up the splashwell access hole to 20"x10" to get at the inside and fitting a matching Armstrong Hatch. I laid out the dimensions and it fits perfectly. I have to fill in a small portion of the two splashwell drain recesses to provide a flat surface at the aft corners.

The plan is to lie in 3 layers of glass down the aft side of the tank enclosure bulkhead and drop them of at 3" 6" 9" aft to lessen the abrupt change of stiffness aft of the Fuel tank bulkhead. Then grind (feather- out) the out side 12" and lay in glass.
Will be stronger than new!

I thought I looked over this boat with a fine tooth comb when I bought it.

[image]http://i56.photobucket.com/albums/g191/fishstu/SeacraftHull006Small.jpg[/imag


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