To Bill: I have considered making a sandwich on my keel. I think my keel
cavity would accept another 1/4 in. (1/8 on either side). If I was to do
this I would make a riveted assembly. However, sheet lead does not come
cheap, so I have opted for other means of increasing stability.
Bernie.
Mark wrote:
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> West Wight Potter Website at URL
> http://www.lesbois.com/wwpotter/
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> I used to do a lot of mass calculations for a number of dense
> materials. The figure that sticks in my mind is 0.45 pounds per cubic
> inch for lead. I will try to get you a better (read more reliable than
> a 20-year old memory) figure this weekend when I'm home (assuming that I
> can find my Machinery's Handbook). Based on that, you would have 12
> inches x 12 inches x 0.1875 for 27 cubic inches of lead per square foot
> of 3/16 stock, for a weight of about 12 pounds per square foot. No
> wonder you were huffing and puffing! That door weighed close to 300
> pounds!
>
> By the way, if you cut metal out of the centerboard, you have to
> subtract its mass from that of the lead which replaces it. If I
> remember correctly, steel runs 0.29 pounds per cubic inch, so you'd only
> gain 0.16 pounds per cubic inch. Assuming that your centerboard is
> quarter-inch plate, you would have to replace about 25 square inches to
> gain a pound.
>
> Good Luck,
> Mark
> P-14 #202 "Apres Vous"
> Silver Springs, NV
>
> Wm. Longyard wrote:
>
> > - - - - - - - - - - - - - - - - - - - - - - - - - - -
> > West Wight Potter Website at URL
> > http://www.lesbois.com/wwpotter/
> > - - - - - - - - - - - - - - - - - - - - - - - - - - -
> > Potterers,
> > Tonight I got lucky. A friend of mine clued me in that a doctor
> > was having his office remodeled, and that a lead-lined door was
> > being tossed out. I jumped in the car, and after Herculean
> > effort (and my wife's help!) got the extremely heavy door loaded
> > in the back of my station wagon. (Oh, I don't know how I get
> > myself into these things!)
> >
> > My intention is to use the lead to add mass to my keel. I have
> > several different ideas how to do this:
> >
> > 1. Use a plasma cutter to cut out triangles out of of my keel,
> > and pour molten lead into the cut-outs.
> > 2. Cut the lead sheet into two profiles of my keel, place them on
> > either side of the keel and glass everything together.
> > 3. Simply rivet the two lead pieces to the sides of the keel.
> >
> > I would like to hear your opinions of these options. Remember, I
> > have a Siren 17 with a swing keel. It looks like I enough room
> > to put a sandwich of lead on the present keel and still be able
> > to retract it.
> >
> > Does anyone know the weight of a 3/16" one square foot of lead?
> > The door is about 20 square feet.
> >
> > Also, I'd like to know if anyone know how to separate the wood
> > from the lead sheet? Are the wood door panels simply glued onto
> > the lead? What kind of glue, contact glue? Anyone know?
> >
> > Looking forward to all your great ideas and suggestions,
> > Bill Longyard