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Here's a DIY demonstration of raising and lowering the 35' mast using a hinged tabernacle, whisker pole, tackle, and manual anchor windlass on a 28' Pearson Triton. The same principal should work for larger masts as well. Sketches and photos are available if you contact me through atomvoyages.com.
Despite the natural advantages of using the boom as a gin pole and dropping the mast forward, the mast must hinge aft on most boats because the jib furler would get in the way and since the mast is stepped forward of boats centerline if it was dropped forward there would be too much spar overhanging the bow pulpit when lowered. And it works out better because the windlass is at the bow and the transom is a good place to secure the mast support roller. In my case, I use intermediate aft shrouds so it makes sense to hinge it to drop aft. If you don't have any shrouds suitable for tying off at the same level as the mast hinge pivot point then you could use halyards to control the mast from swinging sideways. If you had 6-1 tackle you might be able to use your cockpit sheet winch if an anchor windlass is unavailable. Just make sure it's thru-bolted with backing plates and have a second person on a safety line the first time you try it.
Update: A viewer replied to my question of load calculation formula and said the max load on the windless line is H*W/(5.66*L) where H is the mast height, W is the mast weight and L is the length of the gin pole. The load above the tackle without the 4:1 purchase is 4 times higher. In my case the mast is 35'. Pole is 8'. Mast , rigging, pole and raising hardware weigh about 170 lbs so I would guess the load on the windlass line would be 526 lbs without the 4:1 purchase and 132 lbs with it. Adding friction losses for tackle and windlass brings it up to around 170 lbs. This info is useful for you to calculate the size and strength of components required.
Warning: Raising your mast is dangerous so don't try it based on this video alone and make sure you are competent to do it safely. For example, if the hinge assembly failed, the bottom of the mast could shoot forward and cripple you. If a guy line breaks the mast could swing to the side and hit another boat or fall on your crew. If doing this on land beware of overhead power lines that kill people every year.
Parts:
Dwyer DH2150 hinged mast plate available here for $75:
store.sandiego...
Roller is the Attwood Heavy Duty Boat Trailer Roller 10 inches, currently on Amazon for $13. The roller can be supported by 1" stainless tubing with eye and jaw end fittings used for biminis. Be aware that most of the weight of the mast will be on this so ensure the guy lines are secure and the attachment points to pushpit are strong.
For the mast brackets I used 1/8" x 1.25" stainless steel angles, which are stronger than flat plates to resist bending.
The pole brackets are 3/16" x 2" flat plates.
The mast guy line brackets were made from leftover sail track.
You'll need a drill press and welder for DIY.
I used stainless steel for this because I had it in stock and my TIG welder does not do aluminum but if you are having a local metal fab shop makes these up for you then using aluminum will save weight.
We can be reached at atomvoyages.com where you can find articles on cruising and fitting out sailboats. If you have a classic sailboat and want to share your experiences or have questions on fitting out, consider joining the Plastic Classic Forum where I'm a forum moderator and answer questions: plasticclassic...