|Bill and Susan. |
I am new to this but am approaching the same issue. I found a nice extendable system from a local sail boat shop (in the USA, NJ). The owner has them made for him and, as I remember, they seemed expensive for what you got. Their basic besign: two pieces of square pipe that fit inside each other with bolt welded to the sides of the pipe for attachment. In the down position you can trailer the boat. You extend and push up the center pipe (then lock with a pin) for raising the mast. I found a) round pipe is a lot less expensive than square pipe, b) a pair of round pipes fit better, less slop and c) a welder that can do the fabrication at a reasonable price. RSVP to email@example.com and I will try do make a sketch that I can forward. Hope this helps.
The URL of the sailboat shop I mentioned can be found at: http://www.sailboatshop.com/ .
It is a slow site but you can get their e-mail address.