Re: Plywood 12-1/2 - Keel Construction
> Does the plywood 12-1/2 still have the horizontal keelbolts asshown in Boat Design Quarterly and BWAOM?
I'm a little confused. My copy of BWAOM does not show any
construction detail for the 12 1/2 at all. I am beginning to get the
idea the PCB finally created a buildable plan which is shown in later
editions of BWAOM. True? False?
- Oops - I think the final plans were in Boat Design Quarterly. There
was considerable detail, and that's where I saw the alarming
keelbolts. I don't have BWAOM handy, but now that I think about it,
it doesn't show much.
-- In email@example.com, "Peter Vanderwaart" <pvanderw@o...> wrote:
> > Does the plywood 12-1/2 still have the horizontal keelbolts asthe
> shown in Boat Design Quarterly and BWAOM?
> I'm a little confused. My copy of BWAOM does not show any
> construction detail for the 12 1/2 at all. I am beginning to get
> idea the PCB finally created a buildable plan which is shown inlater
> editions of BWAOM. True? False?
I don't have my copy of BWAOM since I've lent it to a friend, so I
can't recall what detail was there. However, the plans have been
completed for 'experienced builders' (in PCB's words) and he has them
available for sale. I've got a copy and they have all the
information I think a builder would need. He has made some other
changes - the rig is now a Solent lug rig (the mainsail is about the
same shape as the jib-headed rig, but the top two-thirds fo the luff
hoists on a vertical yard)and the jib is a balanced-club type, self-
trimming in tacking and not hanked to a stay. Very pretty rig
Regarding the horizontal keelbolts - yes that is still in the plans.
The outer two layers of the keel/backbone assembly (6 layers of 1/2"
plywood total) overlap the lead by approximately 2 inches on the top
and back. The lead keel(750 lbs now) is attached by six 1/2"
horizontal keel bolts (3 on the top and 3 on the back)through the
outer two overlapping layers of plywood. Being a mechanical engineer
myself I was also a little suspect of this, but want to do some
calculations before I jump to conclusions. I was also considering
the vertical keelbolts, but looking at it, the vertical keelbolts
have the potential to start 'splitting' the plywood since some of the
forces will be 'cross-grain' between layers.
Whatever I do, you can be sure I'll have some more discussions on
this with PCB&F before proceeding with the full size boat. I've
almost completed the 1/6 scale model and am finding the shape quite
nice actually. Unfortunately, I've got to go back to work tomorrow
after a bit of time off and my schedule won't allow completion for a
couple of months. I'll put a picture of it in the files once it is
Additionally, regarding the earlier comment about the Haven 12-1/2.
I've looked at it and it is still quite a bit more complex even
though many amateurs have built it. While I do enjoy building - I
enjoy sailing even more. Additionally I prefer the fixed keel.