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Re: Strip: What's the deal with bulkheads?
By:JohnAbercrombie
Date: 10/27/2016, 5:07 pm
In Response To: Strip: What's the deal with bulkheads? (Steve Solomon)

Do (should) bulkheads provide structural support for the hull and/or the deck? Seems plausible, especially in regards to the deck, but a rigid bulkhead also creates a hard spot in the hull which can be susceptible to stress fractures - I’ve seen some recommend using foam or something non-rigid instead.

The 'hard spot' issue is more of a concern with a very flexible bull and deck - which you can find in lightly-built glass boats. The hull/deck shape makes a big difference - flatter areas are more flexible; a hull with a more 'keel-like' shape on the midline will be a lot stiffer.
To be waterproof, a foam bulkhead needs to be quite thick (3" or so), wasting a bit of storage volume.
For a woodstrip or plywood S&G boat a 'rigid' (fiberglass) bulkhead works well. A bulkhead used as a footboard needs to be stronger than a 'normal' bulkhead.

Do (should) bulkheads create water-tight compartments, ensuring positive flotation if the boat is swamped

Yes, and they should be coupled with effective hatch covers.
If you are going surfing or otherwise 'looking for trouble' ;-) flotation inside the compartments is good backup insurance.

I’ve noted that some people specifically don’t want the bulkheads to be water-tight and put in drainage.

I haven't seen that in kayaks. Bulkheads should have a tiny 'vent hole' in the center to prevent air pressure problems.

The basic idea is that if the cockpit area gets filled with water, the kayak will still float (and can often be paddled) since the ends of the boat are still 'dry' and provide flotation. For more on this, check out 'Cleopatra's Needle':
http://www.useakayak.org/recoveries_rescues/cleos_needle2.html

Messages In This Thread

Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 4:39 pm
Re: Strip: What's the deal with bulkheads?
Charles Robinson -- 10/27/2016, 4:50 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 5:07 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 6:05 pm
Re: Strip: What's the deal with bulkheads?
Etienne Muller -- 10/27/2016, 6:09 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 6:49 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 8:37 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 8:24 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 8:59 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 9:24 pm
Re: Strip: What's the deal with bulkheads?
Marc Upchurch -- 10/27/2016, 9:28 pm
Re: Strip: What's the deal with bulkheads?
Nick Schade - Guillemot Kayaks -- 10/27/2016, 10:10 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 10:20 pm
Re: Strip: What's the deal with bulkheads?
Bill Hamm -- 10/28/2016, 12:37 am
Re: Strip: What's the deal with bulkheads?
Bill Hamm -- 10/28/2016, 12:35 am
Re: Strip: What's the deal with bulkheads?
Thomas Duncan -- 10/28/2016, 12:27 pm
Re: Strip: What's the deal with bulkheads? *PIC*
Rob Macks/Laughing Loon CC&K -- 10/28/2016, 1:26 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/28/2016, 4:31 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/28/2016, 5:23 pm
Re: Strip: What's the deal with bulkheads?
Rob Macks/Laughing Loon CC&K -- 10/28/2016, 9:37 am
Re: Strip: What's the deal with bulkheads?
Bill Hamm -- 10/29/2016, 1:06 am
Re: Strip: What's the deal with bulkheads?
Etienne Muller -- 10/27/2016, 6:07 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 6:45 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 8:12 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 9:28 pm
Re: Strip: What's the deal with bulkheads?
Marc Upchurch -- 10/27/2016, 9:34 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 10:16 pm
Re: Strip: What's the deal with bulkheads?
Paul D -- 10/27/2016, 8:35 pm
Re: Strip: What's the deal with bulkheads?
Mike Bielski -- 10/27/2016, 10:16 pm
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 10:33 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 10:51 pm
Re: Strip: What's the deal with bulkheads?
Marc Upchurch -- 10/27/2016, 11:15 pm
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/27/2016, 11:26 pm
Re: Strip: What's the deal with bulkheads?
Rob Macks/Laughing Loon CC&K -- 10/28/2016, 9:19 am
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/28/2016, 10:27 am
Re: Strip: What's the deal with bulkheads? *PIC*
Rob Macks/Laughing Loon CC&K -- 10/28/2016, 11:07 am
Re: Strip: What's the deal with bulkheads?
Steve Solomon -- 10/28/2016, 1:41 pm
Re: Strip: What's the deal with bulkheads?
Bill Hamm -- 10/29/2016, 1:10 am
Re: Strip: What's the deal with bulkheads?
Mike Bielski -- 10/27/2016, 11:11 pm
Re: Strip: What's the deal with bulkheads?
Bill Hamm -- 10/28/2016, 1:01 am
Re: Strip: What's the deal with bulkheads?
Bill Hamm -- 10/28/2016, 12:41 am
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/27/2016, 8:29 pm
Re: Strip: What's the deal with bulkheads?
Etienne Muller -- 10/28/2016, 6:55 am
Re: Strip: What's the deal with bulkheads?
Thomas Duncan -- 10/28/2016, 9:20 am
Re: Strip: What's the deal with bulkheads?
Bill Hamm -- 10/28/2016, 12:39 am
Re: Strip: What's the deal with bulkheads?
Paul Sylvester -- 10/29/2016, 6:22 am
Re: Strip: What's the deal with bulkheads? *PIC*
Etienne Muller -- 10/30/2016, 7:43 am
Re: Strip: What's the deal with bulkheads?
Paul D -- 10/31/2016, 12:48 am
Re: Strip: What's the deal with bulkheads?
JohnAbercrombie -- 10/31/2016, 3:09 pm