mooring bouys

slocum2 · #1 (**permalink**) 03-26-2007

I'm moving out to a mooring and was searchiing for the right size for a 33 foot, 13,000 lb boat subject to currents of up to 2.5 kts. Water depth is about 15 feet and I'm not sure of the chain size.

A 24 inch ball was expensive, and I was looking at an 18 inch. Any thoughts on this?

Thanks

erps · #2 (**permalink**) 03-26-2007

I was on our own mooring system for almost 15 years. I think I made every possible mistake in its design/maintenance.

Most of the successful private mooring systems in our little bay were made up of a rope instead of chain. My final version was made up of large rope with floats to keep it off the bottom with the last six feet attached to chain on a swivel that ran up through one of those hard styrofoam buoys with a big clevis on top. The float just needs to be big enough to float the rope and chain along with the 20 lbs of marine growth that will eventually grow on it. I think we had an 18 incher.

The chain could easily be lifted and inspected and the rope seemed like it would last forever as long as it didn't get caught on the mooring weight and chafe, and it gave it a little shock absorbing qualities.

The mooring balls they typically sell at worst marine warn you not to attach your pennant to the top ring because eventually it WILL rust through and the ring and rod will drop off the float. Avoid using stainless cotter pins or wire on your galvanized clevis pins.

Anyhoo, with this last boat purchase, the boat was a big enough capitol investment that I could no longer sleep at night with her on a mooring buoy, so we're p*ssing our money away on dock rental each month. Arrgh.

sailingdog · #3 (**permalink**) 03-26-2007

Slocum2

I'd be more worried about what was at the bottom of the mooring, rather than what was at the top. The bottom part is what holds your boat in place when the wind picks up... not the top. The top part is also far simpler to replace...

RickBowman · #4 (**permalink**) 03-29-2007

sailingdog,
You might be interested in The Benefits of Helix Mooring Systems
I am installing one in conjunction with an existing 1200 pound slab of concrete that has a 1 inch eyebolt inbeded in it. My boat is about the same displacment as yours and I opted for the round shaft anchor http://www.helixmooringsystems.com/b...tml#roundshaft as it is a more do it yourself project....with scuba of course.
My mooring ball required by the Army Corp of Engineers is a white 24" ball with the blue strip that made it a legal mooring field with their permit issued. Everyone else is only a clingon. Ha!

sailingdog · #5 (**permalink**) 03-29-2007

I've used the Helix mooring systems... they're pretty nice... but care must be taken to install them properly.

hamiam · #6 (**permalink**) 03-29-2007

i would suggest looking into a dor-mor pyramid shaped moorings. offers alot of holding power for the weight. also, if memory serves, the mooring ball is actually an important element of the system as it reduces shock loads.

sailingdog · #7 (**permalink**) 03-30-2007

Hamiam-

While I agree that the mooring ball can help reduce shock loading on the boat, if the underwater portion of a mooring system isn't properly designed and sized, it really doesn't matter much... the first time the winds or seas pick up, the boat is toast. He doesn't say what the underwater portion of the mooring consists of.

Helix anchors, properly installed are far better than pyramid or mushroom anchors. However, not all places have people competent to install a helix anchor.

RickBowman · #8 (**permalink**) 03-30-2007

sailingdog,
You're correct. There is one installer in Michigan, and if you don't live in the southwest part of the state then "rotsa-ruck," <====== Chinease for "abandon all hope", as the install invloves hydraulics on a floating platform making a single Helix install price prohibitive.

imkashmo · #9 (**permalink**) 01-08-2009

Hi There,
I'm installing a mooring system in Kaneohe Bay on Oahu, Hawaii. Its 40 Feet deep, mud/sand bottom. Windward side. Having to submit a diagram, just wanted to see if anybody had experience doing this? Its a 45 Foot Trimaran, 20 Foot Beam (18 ton displacement -according to my research). Mainly need to source the materials. There are already 54 personally installed moorings at the site but nobody has bothered to put up a blog or info.

imkashmoATgmailDOTcom

erps · #10 (**permalink**) 01-08-2009

Quote:

Originally Posted by imkashmo

Hi There,
I'm installing a mooring system in Kaneohe Bay on Oahu, Hawaii. Its 40 Feet deep, mud/sand bottom. Windward side. Having to submit a diagram, just wanted to see if anybody had experience doing this? Its a 45 Foot Trimaran, 20 Foot Beam (18 ton displacement -according to my research). Mainly need to source the materials. There are already 54 personally installed moorings at the site but nobody has bothered to put up a blog or info.

imkashmoATgmailDOTcom

That's a big boat to keep off the beach. If it were me, I would put on the mask and snorkel and take a look at what the others in the bay are doing. Although the moorings I've used have been concrete blocks, they've been for smaller boats in a more protected area.

If I were in your spot, I think I would check locally to see if anyone is installing the helix mooring rods. If they were not available, I would start checking to see if I could get a hold of some used railroad wheels to string together two or three with some B.F. chain tying them together and then some smaller chain coming off the bottom with an underwater float holding it off the bottom and then some 1 inch nylon rope up to my mooring ball. There are some folks advocating the use of large mushroom anchors here as well that appear to hold very well once they are buried. A check of the moorings around you may give you an idea whether a mushroom anchor would work for you.