40' mast raising /stepping

Ifishli · #1 (**permalink**) 12-05-2009

I am trying to devise a way to raise a fairly large mast (40') I am not new to this. On my columbia 7.6 30' mast I have used both a fixed 16' A frame connected to the stanchions and stayed off, and the ginpole method (2x6 with a crotch) anchor the mast down with lines in front of the step and tip it up. A frame worked better for a few reasons.
A frame would be a pain now it would need to be 22' long and made out of heaver tubing. Not practical.
I am thinking a very large hinge at the base. probably custom made my mast is about 8-1/2"x 5-1/4". The boat allmand 31 has 3 lowers and may need chain plate work anyway so the center one could be raised/relocaited to allow it's eye hole to be alligned with the center of the hinge pin. custom gin pole maybe with an attachment point to the hinge step,block and tackle from the gin tip to steam head and halyard to the same point on the pole.
Anybody seen or done a larger mast this way? most information is for trailer sailors and not bigger boats.

JohnRPollard · #2 (**permalink**) 12-05-2009

Early this year, Good Old Boat ran a very detailed article by a couple that routinely raises and lowers the mast on their Cape Dory. I think it was a CD 27, 28, or 30. That was probably the Jan/Feb or March/April 2009 issue.

deniseO30 · #3 (**permalink**) 12-05-2009

Uh... get a crane.. (imho) it will cost less then all the materials you need to build one. sources for crane rentals are sign companies, or crane, and equipment rentals.

zz4gta · #4 (**permalink**) 12-05-2009

Pay a yard.

NICHOLSON58 · #5 (**permalink**) 12-05-2009

The largest owner erected mast I know of was on a custom 78 foot yacht. The owner-builder designed the rigging so that the mast was cabin top stepped on a heavy, hinged platform. The hinge pin was directly in line with the shackle pins on the lowers. The powered anchor windlas was used to back-off the fore stay and mast would pivot down onto a cabin top gallows. The owner and his wife were in their 70's and could lower or raise the mast in 20 minutes. The design was to run the ICW and other places with low bridge clearance.

You could consider making such modifications - or - you could hire the marina service department to step the thing. I suspect that your mast is not only longer than on your previous smaller boats but geometricly heavier. I did a CAD model on ours (80 ft) and found the extrusion calculates to just over 1000 pounds without spreader and standing rigging. I can't imagine the cost of the loss if you dropped & broke your stick or if you damaged stuff around you.

sigmasailor · #6 (**permalink**) 12-05-2009

Find a 35' bridge or something similar and have someone hold the top of the mast from there while you connect all the rigging?
Easiest and safest way is tho use a crane of some sort.

Faster · #7 (**permalink**) 12-05-2009

Tying up between two (preferably larger) boats and using a halyard from each to lift and step the mast is another possible method...

But a proper crane or mast tower is the safest, surest way to go unless the boat's been designed for raising the mast in place. Trying to raise your shroud-pin points to the mast base height sounds excessively complicated and difficult (structurally) to me.

klem · #8 (**permalink**) 12-05-2009

The two common methods that I know of for do it yourself people are a bridge and a cargo boom at a pier. The problem with hooking tackle to a bridge is that the cops tend to take notice (and if you are using a train bridge check the schedule, some people have actually messed this up). The other problem is keeping the boat stationary.

If there is a commercial pier near you, there little cargo booms are often capable of doing it but you usually have to do it at low tide so that they have enough pick.

There are tons of ways to do it, it just depends upon how inventive you are and how much risk you are willing to take. If you look up how they used to do it before cranes, you will find that they had some interesting methods that seemed to work well.

Ifishli · #9 (**permalink**) 12-05-2009

That 78 footer is exactly how I plan on doing it less the power winch. so I guess the hinge step needs to be custom.
I think the profile is 5 lbs per foot =200 lbs +mast head shrouds etc 50 lbs.
at 250 if I hinge the mast at the base attach a 10' gin pole there at 90 degrees to the mast and attach to it a line at 10' up from the mast it should give me a 3 to one leverage ratio on a 40 foot mast and require 3x250= 750lbs of pull to start the mast up from flat and progressively less as it gets more vertical. Any Engineers out there does this sound about right.

NICHOLSON58 · #10 (**permalink**) 12-05-2009

Why don't you just have Wylee Coyote use his ACME mast installer? You know, the one with the dynamite and rockets on it. I think the mast shoots down a long ramp and leaps through the air to land perfectly in the mast step.

Unless you are in one of those areas - Palm Beach to Miami for example, yard rates are not so high that you can't afford the hourly rate. We are in Muskegon Michigan and have been happily surprised at how reasonable and honest the marina service has been. My cousin paid 50 kilobucks for a new topsides AWL GRIP. We paid 10. (sistership 58 feet) They let us do a lot of the prep and did a fabulous job. If you are prepared to step and all standing rigging is ready with nothing but pins to install it won't take more than 30 minutes. GET A QUOTE!