| GENERAL CONSIDERATIONS |
| Before finalising your choice of mooring position with authority or club, consult your mooring contractor as to whether the area is safe for your vessel and that there is sufficient depth of water. |
| Before purchasing mooring tackle please take into consideration the following points: |
| To comply with our current standards, materials must have been manufactured for the purpose of mooring use and must be guaranteed as such. |
| Cheap commercial shackles, although new, may be unusable because of poor thread. |
| Modern, loose laid three strand rope (soft rope) must not be used as a bridle on a swinging mooring because it will unlay. |
| Cheap forged or welded swivels can part company, and if they are the screw type, are unsuitable for mooring use. |
| Materials used in the manufacture of mooring blocks must be of correct quality - e.g. not beach
sand, not salt water. Blocks must not be infilled with scrap, metal, rocks or building debris. They must be one solid mix, not layered. Reinforcing bars or meshing should not be used. |
| Mooring blocks need a minimum of two weeks to set before being launched or used. |
| If you are making a mooring block to be positioned by us, we would like you to consult us before proceeding. The block must be placed where it will have at least two metres of water over it on ordinary high water springs, in order for our boat to lift it. The eye needs a place to attach the rising chain and a separate place to attach a working rope. See picture for a suggested arrangement. |
| SWINGING MOORING FOR A VESSEL OF UP TO 20 FEET LENGTH OVERALL |
| Concrete block |
| Weight approximately 820 kg when immersed in water |
| Length of chain inside from bottom to top with one and a half links protruding to form eye for
attachment. This chain to be ferry chain or similar - approximately 40mm in section (+/- 5mm). |
| Guidelines as to size: |
| round block |
| Diameter 1.54 metre / 5 ft |
| Height 0.315 metre / 1 ft |
| Volume 0.59 cubic metre |
| materials required: |
| 7 bags of cement |
| Aggregate, three quarters to dust |
| 0.8 metres of ferry chain approximately 40mm in section (+/- 5mm). |
| mix ratio (by volume): |
| 5 parts of aggregate to one part cement |
| Bottom shackle |
| Lifting D shackle, 26mm body, 28mm pin. |
| Secured by one of these methods: stainless steel locking strap or two nylon locking straps. |
| Chain |
| 19mm / 20mm new long link chain |
| Scope to be equal to the total depth of water on the allocated position on a 7.2 metre tide |
| Shackles |
| All shackles other than the bottom shackle: minimum of 22mm cross section |
| Secured by one of these methods: welding, stainless steel locking strap, two nylon locking straps, three stainless steel wires. |
| Swivel |
| 18mm stainless steel swivel |
| 15mm stainless steel swivel if the boat is very small |
| Buoy |
| Suitable buoys might be: |
| 75 inch circumference net buoy with short tail of 18mm to 24mm rope and thimble |
| Hippo soft buoy |
| Anchor Marine ABO600 (solid soft yellow buoy with through chain) |
| Total buoyancy to equal at least twice the total weight of all tackle excluding block |
| To be marked with area initials and mooring number in large letters |
| Boat rope/bridle for swinging mooring |
| 20mm multiplait nylon (thicker if the bow fittings can accommodate it) Not three strand rope thimble spliced into lower end plastic pipe or layflat hose for anti-chafe soft eye at boat end |
| pick-up buoy and rope |
| FAILURE GUIDELINES |
| Any chain or shackle measuring less than 15mm in any part of the cross section will result in that component being failed. |
| Chain usually lasts two and half to three years. |
| Boat ropes will be failed where one strand (in three strand) or two strands (in multiplait) are damaged. |
| SWINGING MOORING FOR A VESSEL OF UP TO 30 FEET LENGTH OVERALL |
| Concrete block |
| Weight approximately 1,200 kg when immersed in water |
| Length of chain inside from
bottom to top with one and a half links protruding to form eye for attachment.
This chain to be ferry chain or similar - approximately 40mm in section (+/- 5mm). |
| Guidelines as to size: |
| round block |
| Diameter 1.54 metres / 5 ft |
| Height 0.45 metres / 1 ft 6 ins |
| Volume 0.817 cubic metre |
| materials required: |
| 10 bags of cement |
| Aggregate, three quarters to dust |
| 1.0 metre of ferry chain |
| mix ratio (by volume): |
| 5 parts of aggregate to one part cement |
| Bottom shackle |
| Lifting D shackle, 26mm body, 28mm pin. |
| Secured by one of these methods: stainless steel locking strap or two nylon locking straps. |
| Chain |
| 19mm / 20mm new long link chain |
| Scope for a swinging mooring to be equal to the total depth of water on the allocated position on a 7.2 metre tide |
| Shackles |
| All shackles other than the bottom shackle: minimum of 22mm cross section |
| Secured by one of these methods: welding, stainless steel locking strap, two nylon locking straps, three stainless steel wires. |
| Buoy |
| Suitable buoys might be: |
| 85 inch circumference net buoy with short tail of 20mm to 24mm rope and thimble |
| Anchor Marine ABO870 (solid soft yellow buoy with through chain) |
| Total buoyancy to equal at least twice the total weight of all tackle excluding block |
| To be marked with area initials and mooring number in large letters |
| Boat rope/bridle for swinging mooring |
| 24/28mm multiplait nylon Not three strand rope thimble spliced into lower end plastic pipe or layflat hose for anti-chafe soft eye at boat end |
| pick-up buoy and rope |
| FAILURE GUIDELINES |
| Any chain or shackle measuring less than 15mm in any part of the cross section will result in that component being failed. |
| Chain usually lasts two and half to three years. |
| Boat ropes will be failed where one strand (in three strand) or two strands (in multiplait) are damaged. |
| FORE & AFT MOORING FOR A VESSEL OF UP TO 30 FEET LENGTH OVERALL |
| Two concrete blocks |
| Each weighing approximately 1,200 kg when immersed in water |
| Length of chain inside from
bottom to top with one and a half links protruding to form eye for attachment.
This chain to be ferry chain or similar - approximately 40mm in section (+/- 5mm). |
| Guidelines as to size: |
| round block |
| Diameter 1.54 metres / 5 ft |
| Height 0.45 metres / 1 ft 6 ins |
| Volume 0.817 cubic metre |
| materials required per block: |
| 10 bags of cement |
| Aggregate, three quarters to dust |
| 1.0 metre of ferry chain |
| mix ratio (by volume): |
| 5 parts of aggregate to one part cement |
| Bottom shackle |
| Lifting D shackle, 26mm body, 28mm pin. |
| Secured by one of these methods: stainless steel locking strap or two nylon locking straps. |
| Chain |
| 19mm / 20mm new long link chain |
| Scope for a fore and aft mooring to be calculated in consultation with the mooring contractor, having regard to length of boat, depth of water on a 7.2 metre tide, spacing between blocks and length of bridging rope. |
| Shackles |
| All shackles other than the bottom shackle: minimum of 22mm cross section |
| All shackles to be secured by one of these methods: welding, stainless steel locking strap, two nylon locking straps, three stainless steel wires. |
| Bridging rope |
| 16mm orange polyethylene with thimble at each end. |
| at depth of 3 metres |
| Acts as a spacer: length to equal length of boat plus 6 metres |
| Buoy |
| Suitable buoys are: |
| Hippo buoy |
| Anchor Marine ABO870 (solid soft yellow buoy with through chain) |
| Total buoyancy to equal at least twice the total weight of all tackle excluding block |
| To be marked with area initials and mooring number in large letters |
| Boat ropes |
| Four ropes in 20mm nylon (three strand or multiplait) |
| Two pick-up buoys and a surface joining line for when the boat is away from the mooring. |
| FAILURE GUIDELINES |
| Any chain or shackle measuring less than 15mm in any part of the cross section will result in that component being failed. |
| Chain usually lasts two and half to three years. |
| Boat ropes will be failed where one strand (in three strand) or two strands (in multiplait) are damaged. |
| SWINGING MOORING FOR A VESSEL OF UP TO 40 FEET LENGTH OVERALL |
| The mooring contractor should be consulted as considerations of weight and windage become very important with this size of boat and the specification may have to be increased accordingly. |
| Concrete block |
| Weight at least 1,600 kg when immersed in water |
| Length of chain inside from bottom to top and with one and a half links protruding to form eye
for attachment. This chain to be ferry chain or similar - approximately 40mm in section (+/- 5mm). |
| Guidelines as to size: |
| round block |
| Diameter 1.54 metres / 5 ft |
| Height 0.62 metres / 2 ft |
| Volume 1.125 cubic metres |
| materials required: |
| 13 bags of cement |
| Aggregate, three quarters to dust |
| 1.2 metres of ferry chain approximately 40mm in section (+/- 5mm). |
| mix ratio (by volume): |
| 5 parts of aggregate to one part cement |
| Bottom shackle |
| Lifting D shackle, 26mm body, 28mm pin. |
| Secured by one of these methods: stainless steel locking strap or two nylon locking straps. |
| Chain |
| 19mm, 20mm or 22mm new long link chain depending on weight and windage of boat |
| Scope to be decided in consultation with the mooring contractor having regard to the area |
| Shackles |
| All shackles other than the bottom shackle: Lifting D shackle, 22mm body, 25mm pin |
| Other shackles may be used in consultation with the mooring contractor |
| Secured by one of these methods: welding, stainless steel locking strap, two nylon locking straps, three stainless steel wires. |
| Swivel |
| 18mm stainless steel swivel |
| Buoy |
| Suitable buoys are: |
| Net buoy with short tail of 24mm rope and thimble |
| Hippo soft buoy |
| Anchor Marine ABO870 or larger size (solid soft yellow buoy with through chain) |
| Total buoyancy to equal at least twice the total weight of all tackle excluding block |
| To be marked with area initials and mooring number in large letters |
| Boat rope/bridle for swinging mooring |
| 28mm multiplait nylon or thicker if the bow fitting can take it thimble spliced into lower end plastic pipe or layflat hose for anti-chafesoft eye at boat end |
| pick-up buoy and rope |
| FAILURE GUIDELINES |
| Any chain or shackle measuring less than 17mm in any part of the cross section will result in that component being failed. |
| Chain usually lasts two years. |
| Boat ropes will be failed where one strand (in three strand) or two strands (in multiplait) are damaged. |
| FORE & AFT MOORING FOR A VESSEL OF UP TO 40 FEET LENGTH OVERALL |
| The mooring contractor should be consulted as considerations of weight and windage become very important with this size of boat and the specification may have to be increased accordingly. |
| Concrete blocks |
| Two or more concrete blocks, each weighing at least 1,600 kg when immersed in water |
| Length of chain inside from bottom to top with one and a half links protruding to form eye for
attachment. This chain to be ferry chain or similar - approximately 40mm in section (+/- 5mm). |
| Guidelines as to size: |
| round block |
| Diameter 1.54 metres / 5 ft |
| Height 0.62 metres / 2 ft |
| Volume 1.125 cubic metres |
| materials required per block: |
| 13 bags of cement |
| Aggregate, three quarters to dust |
| 1.2 metres of ferry chain |
| mix ratio (by volume): |
| 5 parts of aggregate to one part cement |
| Bottom shackle |
| Lifting D shackle, 26mm body, 28mm pin. |
| Secured by one of these methods: stainless steel locking strap or two nylon locking straps. |
| Chain |
| 19mm or 20mm new long link chain |
| Scope for a fore and aft mooring to be calculated in consultation with the mooring contractor, having regard to length of boat, depth of water on a 7.2 metre tide, spacing between blocks and length of bridging rope. |
| Shackles |
| All shackles other than the bottom shackle: Lifting D shackle, 22mm body, 25mm pin |
| Other shackles may be used in consultation with the mooring contractor |
| Secured by one of these methods: welding, stainless steel locking strap, two nylon locking straps, three stainless steel wires. |
| Bridging rope |
| 16mm orange polyethylene with thimble at each end. |
| at depth of 3 metres |
| Acts as a spacer: length to equal length of boat plus 6 metres |
| Buoy |
| Suitable buoys are: |
| Hippo buoy or similar |
| Anchor Marine ABO870 or larger size (solid soft yellow buoy with through chain) |
| Total buoyancy to equal at least twice the total weight of all tackle excluding block |
| To be marked with area initials and mooring number in large letters |
| Boat ropes |
| Four ropes in 24mm nylon (three strand or multiplait) |
| Two pick-up buoys and a surface joining line for when the boat is away from the mooring. |
| FAILURE GUIDELINES |
| Any chain or shackle measuring less than 17mm in any part of the cross section will result in that component being failed. |
| Chain usually lasts two years. |
| Boat ropes will be failed where one strand (in three strand) or two strands (in multiplait) are damaged. |
