P-19 Swing Keel & Compression Arch

Along With Other Modifications

By

Mac Davis

Having always had a deep draft boat while I was living in California, I was aghast at the lack of water at my new home on Florida's West Coast. Thus I bought at P19.

Although the P19 wasn't bad in stock condition, there were some things that I felt could be improved:

First, I had to install an electrical system, lights, boom vang, spinnaker-handling gear and backstay. I didn't use Jerry's kit because I didn't know about it, but the way I solved the problem winds up with a split, adjustable backstay.

Then there was a little matter to be dealt with when the forward foam floatation was found to have not set properly during installation (Factory paid to fix this without hesitation)

Then came The DAY. I had on several occasions brushed the widespread oyster bars that guard the entrance to the local channel, resulting in cosmetic damage. This day, I hit one going flat out. The impact was significant, and the damage noticeable. The keel did not slide up, and the boat stopped immediately. After I got back to my boat ramp, I could see that the keel had moved aft and crushed the aft end of the slot pretty badly.

At that point I decided to fix what I considered to be a design flaw that reduced the desirability of the P19 IN MY LOCAL AREA. With the help of a local boat builder, I redesigned the keel so that it now is pivoted at the forward end and swings aft.

Drawing showing the design and layout of the new swing keel.

After several cardboard mockups, I decided that since I always beach in sand or mud, allowing 4 inches of the retracted keel to protrude below the hull would be OK. This turned out to be a good decision since the boat now tracks better under power, and can still beach perfectly level.

Photo of new swing keel protruding through keel slot.

Enhanced photo of new swing keel protruding through keel slot.

Photo of the cabin showing the new swing keel trunk. Note also the compression arch in stead of a compression post.

The swing keel only requires 105 pounds of pull to retract it, so I was able to dispense with all of the tackle involved with the drop keel. This largely compensates for the higher trunk in terms of ability to move about the cabin. The trunk is also sealed except for a 1/2 inch hole in the top for the lifting line. I routed the lifting line through the aft cabin bulkhead to a cleat in the cockpit, which allows me to adjust the keel underway.

Photo showing the swing keel trunk and 1/2 inch opening with lifting line.

Sidebar: raising the keel on a standard P19 creates negative stability under sail. Retracting the swing keel reduces the righting moment, but the overall stability remains positive.

After the keel design was fixed, I conspired with the boat builder to eliminate the other interior problem that reduced the desirability of a P19 FOR ME. We designed an arch to spread the compression load from the mast to the hull at the sides, rather than at the cabin sole. The Arch is made of a plywood, carbon fiber and epoxy sandwich. It attaches to the sides of the hull through the liner. This freed up a great deal of mobility space and makes the bed a lot more comfortable.

This photo shows the newly cteated open space in my P-19's cabin with the swing keel and the compression arch. I'm the handsome guy looking at the camera

Here is a photo showing the compression arch as mounted on the port side of my P-19.

And one showing the arch mounted on the starboard side.

I'm not finished yet. The next phase will extend the V-berth over the Porta-Potti area permanently, eliminating the little notch. Cabinetry will convert the Porta-Potti recess to a storage cabinet, and I also intend to create a small locker where the notch in the V-berth is now.

The Porta-potti will relocate to the stbd quarterberth, tucked back out of the way. When it's slid forward into position, the user can stand with head out the hatch in a more normal posture. This will eliminate the stbd quarter berth as a bunk, so I installed access hatches so that the space aft would be accessible from the cockpit.

The last installation planned will be a 10 gallon rigid water tank located under the v -berth and plumbed for outside fill and to the sink.

I forgot to mention that I installed an instrument panel (knotmeter, compass and 12 volt utility plug) permanently in place of the lower hatch board, and capped it with a 3-inch wide step (seat). This gives me a convenient way to rise from the cockpit seat to the cabin top when lifting the mast, and eliminates the need for a mast raising system.

My idea all along has been to optimize the P19 for my local area, and my sailing habits. I want the ability for a couple to overnight comfortably, but don't envision long voyages or more people on board. I also really like tinkering with things, to the degree that I am sometime accused by friends of starting new boat projects to avoid sailing.

Regards,

Mac