Raising a Centaur Mast using a Gin Pole
Text extracted from WOA Forum Discussions
I have the 'pole' for this. It's wood, about 8 feet long with a piece of plywood screwed at one end, shaped to fit around the mast. The idea is that with the mast on deck with its heel bolt in place (the top needs supporting above the taffrail, using an A-frame), the pole fits close to the bottom of the mast and is guyed in a vertical position.
The mainsheet tackle is rove between the top of this pole and the stem head. Lift the mast as high as possible by hand/clothes-prop or similar and take up the tension on the tackle at the bow. Then haul away on the tackle, steadying the pole with the guys, and up it goes, ending up vertical with the pole now horizontal between the mast step and the bow. It's essential also to use two halyards as guys on the mast itself, and keep them tight and closely controlled.
There are two main difficulties (aside from getting enough helpers): (1) the initial pull required is very hard, as the mechanical advantage at that point is poor and (2) there's a marked tendency for the mast to slew off to one side, which could have disastrous consequences for (a) the bolt through the step and (b) any nearby boats. The solution to the first is just to have plenty of beef on the tackle - perhaps take the hauling part to a winch - and to the second is to take the guys as far away laterally as possible and have a turn round a fixture to take the strain.
If you look on t'internet there are many demonstrations of how - and how not - to do it, by this technique and others. I think the #Centaur is just about the biggest boat on which you can safely do this by hand.
6th November 2018 5:36 pm
Utube video link here 
Centaur Gin Pole design articleFile:CCI27112018.pdf