I'm helping a friend replace a s/s under sole water tank with 2 new
ones. The old tank was held in place with 2 pieces of 2x4 that wedged
the tank against one bulkhead on the aft end and with the 2 pieces on
2x4 wedged into another bulkhead on the fwd end- so the tank was held
in place longitudinally by only the end of the 2x4 - with the 2x4
positioned on the "hard" top edge of the tank where the welded edge
was. Eventually the welds cracked from the concentrated pressure of
the 2x4, and the tank leaked.

So how to hold the new ones - it's about 9" to the bulkhead in front.
The tanks lie about 3" above the FRP hull.

The new tank sould come with hold down brackets that clamp over indentations
in the tank, and screw into the hull
Joe


"santacruz" wrote in message
...
I'm helping a friend replace a s/s under sole water tank with 2 new
ones. The old tank was held in place with 2 pieces of 2x4 that wedged
the tank against one bulkhead on the aft end and with the 2 pieces on
2x4 wedged into another bulkhead on the fwd end- so the tank was held
in place longitudinally by only the end of the 2x4 - with the 2x4
positioned on the "hard" top edge of the tank where the welded edge
was. Eventually the welds cracked from the concentrated pressure of
the 2x4, and the tank leaked.

So how to hold the new ones - it's about 9" to the bulkhead in front.
The tanks lie about 3" above the FRP hull.

The concentrated load of the 2x4 wedge caused the old tank to fail.
Make sure you don't create a point load on your FRP hull or your new
tank may survive at the expense of your boat. Ideally you want tank
brackets or straps anchored to existing strong points--bulkheads and
ribs the first choice. Lacking good radius, your longitudinals might
not have the strength for a big tank. If you decide to glass in new
transvers anchor points, spread the load. Build up a thickness of pad a
good six inches beyond the ends of your new support and carry pad and
bracket all the way to a longitudinal if possible. Good luck.

santacruz wrote:
I'm helping a friend replace a s/s under sole water tank with 2 new
ones. The old tank was held in place with 2 pieces of 2x4 that wedged
the tank against one bulkhead on the aft end and with the 2 pieces on
2x4 wedged into another bulkhead on the fwd end- so the tank was held
in place longitudinally by only the end of the 2x4 - with the 2x4
positioned on the "hard" top edge of the tank where the welded edge
was. Eventually the welds cracked from the concentrated pressure of
the 2x4, and the tank leaked.

So how to hold the new ones - it's about 9" to the bulkhead in front.
The tanks lie about 3" above the FRP hull.