Centerboard Lead Counterweight, Lead Ingots

This morning I was able to get some lead smelting work done, but this afternoon I've got to get going on the "honey-dos."  I have made the lead pour into the centerboard socket to keep it from floating back up into the trunk, but if it hits something it can still swing up.

Lead CB Weight in its Pocket

50 Pounds of Ingots

Lead Ingots

 This was the bottom of the pour.  The pits are due to gas bubbling up to the surface.  The top side was quite a bit rougher, since that's where the bubbles were going.  I have it smoothed down quite a bit, but still some to go.  The low spots on both sides will be filled with thickened epoxy.  The area needs to be smooth, because this is a part of the centerboard that will be submerged.

I spent the rest of the morning pouring ingots.  This bucket contains 50 pounds, and right next to it you can barely see another bucket that contains 40 pounds.  I'll need another 110 pounds or so to finish the ballast.  The ingots will be placed in burlap bags--20 pounds of lead per bag, and the bags will be placed under the floorboards.  Works out to eight 20-pound bags--four bags on each side of the keel.

Here are some of the ingots.  I have a standard lead mold that makes two 1-pound and two 1/2-pound ingots at a time.  On the left are two ingots I made by pouring lead into corn muffin pans.  They average about 1 1/2 pounds each.  

All this reminds me of when I used to pour my own diving weights back in the 60's.  We were much less careful back then--no respirators or face masks.  That's probably why I have so few brain cells left.

Centerboard Edge Filler

Today I got some more work in on the centerboard (CB).  Below you can see the centerboard glued together and all clamps removed.  You can also see that I have cut a rabbet or groove in the leading edge of the board.  The rabbet also goes around the trailing edge of the board, which you cannot see (the trailing edge is on the rightmost end of the board).

Centerboard, Glued and Rabbeted

Router Table

This is my trusty router table I used for cutting the rabbet.  It is clamped to the Black & Decker Workmate folding bench my dad gave me about 40 years ago.  There are a couple spots in the rabbet that are wider because I wiggled the board a bit.  I might have been able to do a better job with the router hand-held and a fence mounted on it--but then again I  might have done a worse job!  Well, I decided on the router table and I think it was a good decision.  The rabbet is OK and any wobbles will be filled with epoxy.

CB Rabbet Filled

This is the rabbet right after the first application of thickened epoxy filler along the leading edge.  I thickened the epoxy with approximately two parts wood flour to one part colloidal silica.  The filler looks a little rough here.  After a couple hours I went back and smoothed it down some with a gloved finger dipped in denatured alcohol.

Filler Smoothed

Here's the filler after some smoothing with denatured alcohol.  It's not perfect, but this will save me a lot of sanding.  Getting the epoxy as smooth as possible while it is pliable saves many hours of sanding or chiseling later.  The edges of the centerboard will be ground down to a somewhat airfoil shape, bullet-nosed in front with a longer taper in back--so the edges of the tapers will be all epoxy.  The epoxy will make it much less susceptible to damage by underwater objects.  I plan to also add dynel cloth and an epoxy/graphite mixture to the leading edge.  (Graphite/epoxy will also be used in the final coat on the entire board to make it slide more smoothly in the trunk.)  Why am I being so "anal" about protecting the centerboard?  It is going to always be inside the trunk and next to impossible to get to without a crane to lift the boat off the trailer (I have some other ideas about how to raise the boat but they may or may not work).  So you can see why I am doing all I can to protect the centerboard and its trunk from damage.  I may not even know about any damage until it is too late and water has infiltrated the board.  Besides the obvious problems, this can make it swell and become permanently stuck inside the trunk--not a good thing.

Keel Lead Pours, Gluing Centerboard Halves

Keel Front End, Ready for Lead Pour

Shown at right is the front end of the keel ready for the first lead pour.  I have clamped concrete blocks to the sides because the weight and heat of the molten lead could cause them to spread or even separate.

Lead Starting to Melt

Here is some of the scrap lead I purchased starting to melt.  I purchased a standard cast iron pot to serve as the melting pot and borrowed the bottom section of a turkey fryer to use for heating the lead.  At this point I have on a respirator and will be donning a full face mask before I begin pouring lead.

Melted Lead -- Dross Removed

 The lead is melted and ready to pour.  I removed the dross (impurities) earlier with a slotted spoon.  (More about that later.)  Any impurities are very easy to remove because they are all so much lighter than lead they float immediately to the top.

Lead Pour in Keel Front

 This shows the approximately 15 1/2 pounds of lead just after it was poured into the front section of the keel--just in front of the centerboard trunk.  There was a lot of smoke from charred wood, but it had mostly died down by the time I took the picture.  According to Chesapeake Light Craft (CLC), this does not hurt anything.  They call it "flash charring."

First Lead Pour Behind CB Trunk

Here you see the rear section of the keel after the first pour.  You can't see any lead from this angle, but you can see a little of the smoke.

First Lead Pour Viewed from Above

Finished Lead Pour, Behind CB Trunk

 First rear-section pour from above.  You can see the lead and just barely see  smoke toward the aft end.  The only concrete blocks I could find were 16" long, and the opening is 22" so I had to use two on each side.  The clamp in the middle is just tight enough to keep the blocks from spreading, but not tight enough to squeeze the keel sides inward.


Rear section after the second and final pour.  Hard to see, but the lead has been left about 1/2" below the top of the keel.  A wood cap will be fitted in place over the lead and over the hollow section behind it.   There is 92 pounds of lead in this section.

Dross

 The pile of dross and other odds and ends I removed from the molten lead.  In the next picture you'll get a better idea of how high the pile is.  I bought scrap lead and it had quite a bit of impurities and other stuff attached to it here and there.  I got most of the dross out and what was left looked very nice.  I had about 8 pounds of lead left over which I have made into small ingots for now.

Some of the Lead Working Utensils

 Here I laid the utensils I used to remove the dross against the pile of dross.  I purchased a cheap slotted spoon for the job, but right after the first pour the bowl of the spoon just fell off.  Apparently it was soldered to the handle and the heat melted the solder.  Luckily it happened between pours and I had a chance to run out and buy a solid stainless steel spoon--well not really, it is a spaghetti lifter, but it was all I could find in a hurry.  Turns out it worked very well.

Gluing the Centerboard Halves

Centerboard Halves

 The two halves of the centerboard are laid out and ready for me to glue.  The rectangular holes are for lead.  As CLC points out, the weight is to pull the centerboard down not for righting moment--but I think 20 lb. that far down will definitely help.

Hole for Lead Weight

 A closer view of one of the holes shows the rabbet cut out all along the outside edges.  When the two halves are glued together this will leave a hollow area around the hole, so that when the lead is poured in it will flow into the hollow.  That will hold the lead in place.

Gluing Centerboard Halves

And, finally, the centerboard halves glued, clamped, and weighted.  One paint can wasn't full so I added more weight on top.

Keel Assembly

Gluing Port Side of Keel to Centerboard Trunk

A fair amount of work was accomplished over the weekend.  The port side of the keel was glued to the centerboard (CB) trunk, as shown here.  The port keel side is on the bottom.  You can barely see 1" thick blocks that are there to keep the CB trunk from being squeezed in by the clamps. 

Aft Section: Gluing Starboard Side of Keel to Trunk

I replaced the thermometer later with a $10 digital thermometer/hygrometer that I hope will be more accurate.  And it keeps a record of 24-hour lows and highs.  That will be useful.


Next, the starboard keel side is glued to the trunk.  Shown here is the rear section, from the trunk to the aft end of the keel.  Full paint cans make useful weights for gluing.  You can't see it but there is a thin piece of wood under the aft end of the keel to keep it from being bent out of shape--it tapers, remember?

Forward Section: Gluing Starboard Side of Keel to Trunk

Gluing Port Side of Keel to CB Trunk

A couple more pictures from different angles.

Assembled Keel/CB Trunk

The assembled keel.  There a few more things that were done after this picture.  Some filling and sanding, and I used a router to round over the front edges of the trunk (which will be inside the cuddy) and the bottom edges of the keel.

The keel is ready for the lead pour now.  I am having a lot of trouble finding lead.  It was supposed to be easy to get from tire shops (used balancing weights), but that is turning out to not be so.  I have one more store I am going to try.  I am also in contact with the local scrap yard, where they keep saying they will get back to me, but then never do.  Lead shot is also an option, but it is expensive and I'll have to pay a lot for shipping.  The problem with lead shot is that it contains about 5% antimony, so I'll be paying extra for metal I don't want and that will take up more volume.  So, I'll keep up the search.  I hope to have the lead in time to do the pours this coming weekend.

Keel Blocking, Noseblock Glued

Gluing Up the Keel Blocking

It's a little hard to see, but here I am gluing in the blocking that goes between the two sides of the keel.  (Again, no effort was made to keep the shot level--just to include everything as much as possible.)  The keel is hollow because lead will be poured into sections of it to add stability.  92 pounds of lead will go into the compartment just behind the centerboard trunk.  The opening for this is just in front of the cans of liquid that are weighing down the vertical blocking. The vertical blocking, besides being a structural component, is used to help contain the lead.

No lead will be added to the rear section (behind the vertical blocking) to maintain proper balance fore and aft.  There will be another 15 1/2 pounds of lead ballast added to the section just behind the noseblock and in front of the centerboard trunk.  You can see this better in the picture of the noseblock being glued in place below.  Another 160 pounds of lead shot will be added later beneath the floorboards for a total of about 268 pounds of ballast.  This makes the PocketShip a very stable boat for its size and, according to the designer, capsize-proof.  The boat can be knocked down by an eight-foot or higher wave (not likely inland) but the ballast provides enough moment to make the boat self-righting, providing the hatch is closed and the cuddy (tiny cabin) is not flooded.

While also on the subject of safety, the boat is also supposed to be "unsinkable," barring a disaster that tears it apart.  The flotation chambers are filled with closed-cell foam (unlike the Titanic).  There is a big chamber in the nose, and more along the sides and under the cockpit.

The other thing I did today was to glue the noseblock to one side of the keel.

Gluing Noseblock to Starboard Side of Keel.

You can see the small area that will contain more lead ballast just behind the noseblock and in front of the centerboard trunk.  Hard to believe this small space will hold 15 1/2 pounds of lead.  Shows how heavy that stuff really is.

Also note the small 3/8" diameter rod in the centerboard pivot hole.  It is there to make sure the holes are all perfectly aligned.