Mast Crane

This project I completed in the fall in time to use it to lower my mast.  Normally this is a three man undertaking but Bob and I decided to give it a go with just the two of us.  The results were incredible.  Bob stood at the base of the mast ready to assist if needed.  I stood between the arms of the "A" frame and, with a little push from Bob, was able to lower the mast down quite easily.
The unit I build was slightly modified from the unit shown at  At "Chip Ahoy" Homeport, they mention attaching the crane arms to the forward shroud attachment points.  The ones on the Christopher-Jin have clevis pin holes that point fore and aft which would not allow the crane to pivot as shown.  So I made aluminum "L" brackets from extruded angle aluminum and attached them permanently under the stanchion bolts.  This also allowed me to make the arms slightly longer.  (Longer Arms = Greater Mechanical Advantage)
I tested lifting the mast once it was on the Mast Stepper.  It was a bit of a pull but it did go up un-assisted.  This coming spring (2010) we'll give it a go all the way up.
The other modification we made was to put a pair of triple blocks at the working end.  One of the blocks has a becket to add one more layer of mechanical advantage.  I wanted to be able to raise and lower the mast while in the the event I decide to try the Erie Cannel which is said to have low bridges.

The forward end of the arm poles are attached to a 1/4 inch, 4"x4", 6 inch long aluminum angle.  I bought the aluminum materials from for under $60.  I started with 7 foot long poles and trimmed them to fit.  I used stainless steel rivets and hardware.  One arm is riveted to the big angle and the other is wing-nutted to allow folding for storage.  The "pinch blocks" are made of teak with a hole drilled down between the faces.  They are wing-nutted to the big angle.
 At the end of the 2009 season I stored the Mast Crane in place, still attached to the Christopher-Jin.  It was ready to go to step the mast at the start of the 2010 season.
The mast lifted quite easily with MOMM single-handing the lifting tackle.  I stood in the cockpit watching for any line tangles.
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