Removing the Keel from a Potter 15

Today we removed the keel from the Potter 15.  It was a bit more difficult that I had hoped, but not really all that hard.  I had hoped I could just slide the boat back on the trailer and then lower the keel enough to get it out.  But the rollers on the trailer were so stiff that the boat would not budge!  I knew I needed new rollers and new bunk carpeting, so I decided to try and get the boat off the trailer.  This will give me a chance to work on the trailer while I am waiting for the keel to get back from the galvanizer.

Step One:  Lower the trailer tongue and block up the back of the boat.  When you raise the tongue back up, the back of the boat will be off the trailer.

Step Two:  Raise the tongue high and block up the front of the boat, leaving room for the trailer to get out.  After you slide out the trailer, add some more blocks and support for the boat so that it is secure.

Step Three:  Position one person inside the boat, and one person under the boat.  Lower the keel until it touches the ground, then disconnect the line and hardware.  Together you can lift the keel off the pin, and pull it up and forward inside the cabin.  It weighs about 80 pounds, and in the confines of the Potter 15 cabin it is a bit tricky.  I left that up to a young friend with a strong back (thanks David).

The next step will be to take the keel to the galvanizer in Ballard.  They will strip off all the old coatings in an acid bath and then hot-dip galvanize it.  I am estimating it will cost about $75 for the process if I can talk one or two more people into taking theirs in at the same time.  

Back to Book Work

After a long break, I am getting back to work on the text of my book about making Stirling Engines. I am happy to say that the end is in sight.  And I am enthused again about the new concepts that are used in these engines.  The first of the three designs has been up and functional for a long time. The second and third engines are almost ready for their testing.  The big tasks that remain to get this project ready for press is to finish up the sections of the book that deal with the step by step assembly instructions, and to finish the assembly and testing of the last two engines.

The thing that makes this project so special is that the reader will be able to assemble a low temperature differential (LTD) Stirling Engine that will run from the heat of the hand, and the project can be completed with common hand and power tools.  A machine shop is not required.

These engines run with a 20 degree temperature differential.  That means that if your hand is 90 degrees or warmer, and the room is 70 or below, the engine will work from the heat of your hand.  They also have very impressive performance in direct sunlight.

I am not sure if I still have a publication deal for the book or not.  My long break from writing may make it necessary for me to find another publisher.  One way or the other I hope to get this information out there for the Stirling Engine community to enjoy.

I want to thank all those who have been enjoying and commenting on the YouTube videos.  I have had the chance to help out a few builders and answer some interesting questions as a result of those videos.

Take care!

Jim