J/30 Class Association

Club crane design for un/step J/30+ masts.

Posted By: Georges

Club crane design for un/step J/30+ masts. - 03/23/19 04:10 PM

Stepping/Unstepping a J/30 mast is billed about $450 each way in Massachusetts those days.
My club has existing cranes but not high enough to go comfortably above the spreaders when the tide allow access to our camels.
Juggling with ideas to address this: like finding a scrapped 50' mast still proper to go to 200 pounds (we have bigger boats in the club), rig it next our existing cranes + foolproof manual windlass.
Anyone have experiences to share in that matter?
Cheers,
Posted By: D. Bartley

Re: Club crane design for un/step J/30+ masts. - 03/24/19 02:07 AM

We attach our crane just below the spreaders... It has worked well for us many times.
Posted By: Georges

Re: Club crane design for un/step J/30+ masts. - 03/24/19 02:46 PM

Thanks Dennis. Sure as it did for me.
My question was less about how to step/unstep the mast, that getting possible experience from those that design an ad-hoc crane (read less expensive than the typical 1 - 2 tons service crane most of the clubs have) for this purpose.
Especially the fool-proof mechanism, since as a club facility, you want to do a decent job at limiting injuries and costly oops.
Thanks,



Posted By: j30sailor

Re: Club crane design for un/step J/30+ masts. - 04/16/19 12:25 PM

I've used a crane and the club hoist, but the best way for us is to use a gin pole. A local J-29 had one that consisted of an old mast with three guide wires and a 3 to 1 pulley. Was the easiest setup and safest experience I've had. I've also used a two pole setup that attached to the chain plates with a pulley at the junction at the top and fore and aft guide lines. Worked equally well.
Posted By: Georges

Re: Club crane design for un/step J/30+ masts. - 04/19/19 08:34 PM

Thanks Rusty appreciated.

We have a few scrapped mast in Boston area that could be used as ginpole.
Although a J30 scrap mast seems to have a bit of a premium around Boston vs. less known boat.
Was the gin-pole you saw also a J29 mast?
Would you have any picture of how it was rigged?

I am thinking indeed a gin-mast stepped (but 3 way articulated) on the peer at the base of our crane, a main backstay passing through a block at the top of our crane to get a good angle + two guide wires and a 40:1 scrap winch preferably self-tailing for safety.


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