They go wherever you decide you are going to plant your butt. As far as I'm concerned, their only function is to provide a surface to which you can attach a square of black foam. That foam is raised just high enough above the bottom of the kayak so that you can slide your kayak seat beneath it and have the seat held securely by friction. Here are links to two photos --

hib brace alone

hip brace and seat   

Some people think the hip brace helps them while paddling, but I have plenty of kayaks without such braces and they work just fine.

   If you ask a sea kayaker what the difference between a rec boat and a sea kayak is they will say,.......you ride a rec boat and you put on a sea kayak. 

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What they mean to say is that if fits tight. The hip braces are to allow hip input to "edge" the boat or to "roll" the boat.  Chances are you haven't gotten into those things yet either. Both items can be done without hip braces.  But they are not near as easy to install later than before the deck is installed.  They install next to where your hips are.  ;-)

Basically they get "glued" to the bottom of the combing at the seat.  Should be filleted in and covered with one layer of cloth. They can be foamed or not. They usually provide a lower point for attachment of the back band. 

   The sectional directions definitely have you installing the hip braces well after the deck is installed.  I wonder why.

 on your question on the hip braces being installed after the hull and deck are put together, it's in large part due to the design on the shearwaters (all of the shearwater series shares this chracteristic) where the hip plates extend from the deck to the floor of the kayak.

since they go from deck to hull floor it would be a bit challenging to install it to the deck or hull first as you would then have to mate it to the other side perfectly...and you would not have any real advantage from ease or quality of assembly.

on some designs, the hip braces extend down from the deck and don't touch the floor (e.g., the night heron and petrels).  in those cases they are installed on the deck  prior to attaching the hull to deck. 

h

Sorry...still have the same quesiton.  Where is the PINE strip, on the top (pink) or the bottom (green).  Thanks!   

Hi Cudo, 

I built my shearwater a while ago....but i seem to recall two small blocks of pine with the kit...is that what you are referring to?

if it is, they are there if you want to use a wood screw to attach the backband webbing to either the side of the hull or the hip plates.

i did not use the pine and instead replaced the wood screw with a machine screw and attached the webbing to the cheak plates by through-bolting the webbing.

i may have a picture somewhere in my archives if i am on track.  if i am not, could you send a picture of the pine.   that's not a component of the main structure as far as i can recall so i am trying to sort out what we may be missing.

h

The pine strips go at the red mark, attached to the underside of the deck. The hip brace can then either be glued to the pine block or attached by screws.

The hip brace is attached at the hull by wood-flour epoxy.

You can see a round spot on my black foam where I had once attached the back-band by running a screw into the pine strip. But I'm pretty tall and wanted my back-band up higher -- hence its current attachment point.   

   Ahhhh.  Thank you Birch2. That is what I needed.

My insticts were right, but I really appreciate the affirmation of how this is done.

-jc