Some good news
and some not so good
...
First thing I did this morning was to take some measurements so that I had an idea of the forces involved. Here there are:
Mast weight: 50 lbs
Distance from rotation ball to mast center of gravity: 14'
Distance from rotation ball to point of lift (jib tang): 17'
From this I deduced that I needed to lift about 40 lbs
Angle between mast and lift strap: a little over 6 degrees
From this I caculated that the force on the strap would be around 400 lbs: 40lbs * SIN(6degree)
This should not present any over large stress on the ball, the lift strap, etc.
Next, I started rigging a loop around the mast, connected to the main halyard (so that I can lock it at the level of the jib tang, and lower it once the mast is raised), with two temporary stays connected to eye strap on the wing supports to prevent sideways motion. I connected the winch strap to the loop and started cranking. Even though the numbers from my calculations looked good, the stress on the loop scared me somewhat and the shackle connecting the halyard scratched the mast.
So I decided to go back to the original idea (using the forestay to lift).
Plan B: I connected the temporary stays directly to the Jib tang (I figured I would leave them connected while sailing and simply tie the lower ends against the mast). I connected the winch strap to the forestay with a shackle. Time to start cranking. The lifting strap gets very taught, but things look good. I'm much more confident in this system that my previous loop around the mast. The temporary stays are very effective at keeping the mast reasonably in line all the way up. The mast stays sideways almost 2/3 of the way up, then slowly rotates fore-aft. Success, the mast is raised
.
Now, le's reverse the maneuver. As I start lowering the mast, it stays in its fore-aft position and the rear part of the mast foot aluminum casting binds against the SS bolt that holds the ball. To ensure the mast remains sideways, I then connect the main halyard to the winch strap (along side the forestay) so that the strap pulls on both the front (forestay) and back (main halyard) of the mast. Why didn't I think of that sooner?
2nd attempt at lowering the mast. The halyard is not tight enough and the mast sill rotates as it goes down. The heel of the mast step casting forces it back sideways, but I don't like the stress so I crank everything back up to tighten the halyard.
3rd attempt. This time the mast stays sideways as it goes down. However, there's a couple of jerks and then, as the mast is almost down, the front part of the mast step casting flies off!
I lower the mast the remaining foot or so to the ladder I use to prop it, and survey the damage. Sure enough the entire forward part of the mast step casting is gone (see picture).
The couple of dents in the middle of the rounded part of the casting are due to my first attempt at lowering the mast when it bumped against the SS bolt. The third one more to the side is from my 2nd attempt.
I can't determine what forced the casting to break. The mast stayed sideways the whole time I was lowering it, and I can't see any marks of stress on the crossbar. I'm puzzled
Did the SS pin get caught? It doesn't seem long enough the reach the big nut that attaches the ball bolt to the crossbar.
It doesn't look like this should prevent the mast to function once up, but I still need to replace the casting (I don't know how much of a problem I have with the broken casting). Matt, if you read this, can I order the mast base (37641001 I believe) and rivet it?