Glassing in a bulkhead question

[Chum Bucket]

I cracked/broke a bulkhead at about midship on the backside of a rather large swell. Obviously the hull flexed on impact. This bulkhead goes outboard of the stringer.

While demo'ing the damaged portion, I noticed Bertram did not cut the wood to actually fit the bottom of the bulkhead against the bottom of the hull. There was a 3/16"-1/4" gap and then heavily tabbed on both sides maintaining this space. Seems like I read something on this site about this but can't find it now. I tabbed the repair with 4 layers of 2408 while maintaining this gap, but would like to know what's the reasoning behind this?

[Rawleigh]

It keeps from creating a hard spot in the hull that can cause cracking, I believe. Capt Pat will let you know for sure.

[Pete Fallon]

Chum Bucket,
Raleigh is correct, bulkheads directly on to the hull will create hard spots and when you look down the sides of some boat brands you can actually see the spots(where bulkheads are placed against the hull itself) from the outside. Some of the newer boat building companies use a foam spacer that does the same thing(preventing hard spots).
Pete Fallon

[Chum Bucket]

Thanks guys. Glad I left the space. Several of the local dock 'experts' were saying that was a manufacturing flaw and the bulkhead should be against the hull. I just could not believe Bertram would have left the gap for no reason.

Love this site...

[mike ohlstein]

Bertram made plenty of mistakes. That's why they're out of business.

This just happens to not be one of them......