Tetrahedron Mooring Puller

*Witzend* · 11-03-2009, 07:11 am

This always gets a raised eyebrow from passers by when we pull or place our 200lb mushroom. Easy to build works great.

*BobM* · 11-03-2009, 07:36 am

Cool rig, but will it work for a 500lb mushroom, which is what I have to use for a 30 footer. I can't believe your insurance company lets you get away with 200lbs. That's a lunch hook in most areas!

*Ross* · 11-03-2009, 10:06 am

Used tractor tires and tubes and a welded frame would be very safe and strong.

*larryw* · 11-03-2009, 10:22 am

Great stuff! I love all that homemade machinery and make-it-work stuff! In a former life, I did ASME code welding and fitting to x-ray quality. Used to take a little engine-driven generator/welder to Glamis on T-day weekends. Working one day fixing broken sand toys for others would pay for all the food, fuel and beer for the weekend. In the army I was on an army tugboat, and aboard a 100-ton BD (Barge Derrick, army-speak for floating crane) I still like to build stuff for the boat and motorcycle, although not having a shop or even a decent garage puts a damper on it. Is your puller pinned together to break it down and store it?

Maine Sail · 11-03-2009, 02:04 pm

Quote:

Originally Posted by BobM

Cool rig, but will it work for a 500lb mushroom, which is what I have to use for a 30 footer. I can't believe your insurance company lets you get away with 200lbs. That's a lunch hook in most areas!

Min suggested weight is about 300 Lbs. but that is a bare minimum.

Witz,

I don't understand why you would pull the mooring each year. Mushrooms can take months to properly set and bury into the bottom. It takes a while for them to screw themselves into the mud.

Ours now has a funnel cone deep into the mud where the chain moves around creating a cone effect in the bottom. To inspect the shackle the diver has to reach his arm into the funnel cone to feel the mushrooms eye and shackle..

Why not just winter spar it and drop the chain to the bottom. This is standard practice around here?

P.S. Cool rig...

*Witzend* · 11-03-2009, 05:16 pm

Quote:

Originally Posted by Maine Sail

Min suggested weight is about 300 Lbs. but that is a bare minimum.

Witz,

I don't understand why you would pull the mooring each year. Mushrooms can take months to properly set and bury into the bottom. It takes a while for them to screw themselves into the mud.

Ours now has a funnel cone deep into the mud where the chain moves around creating a cone effect in the bottom. To inspect the shackle the diver has to reach his arm into the funnel cone to feel the mushrooms eye and shackle..

Why not just winter spar it and drop the chain to the bottom. This is standard practice around here?

P.S. Cool rig...

"Winter Spar It". What is that? We have a serious ice problem on the Elk. Fresh water, strong currents with the right wind direction destroys everything and will tear any mooring ball right off and carry it away. In Feb. 2004 the Elk completely froze over. When it started to break up I watched my dock and many others get destroyed in slow motion. Nothing can stop these forces. This is why we pull it and so does everyone else on the river. The bottom is 2 ft of soft mud. The mushroom digs in almost immediately, have never had it move. My biggest concern is the possibility of the keel getting on top of it in an extreme low tide. I wrapped a motorcycle tire around the rim of the mushroom to mitigate any damage if this ever happened.

The rig is completely collapsible for storage, just take the bolts out. Maybe add more flotation to handle heaver loads, it is strong by design, triangles.
I use (2) come-a-longs to pull the mooring, that allows me to leap frog, otherwise I run out of scope.