Rigging

We make rigging in wire and rod and we have three types of presses to suit any kind of rigging work. We are also able to modify rigging on yachts whilst they are moored on the quayside outside our workshops. We are able to manufacture all types of rigging accessories in any size from tip cups to double back stays .

spiral cable tighteners		spiral cable ends		rod ends
large cable tightener built by us for ø26mm cable installed on the 32m yacht 'Bartabas'
mast jack		mast jack		mast jack set

Mast Jack Regulation

The use of a piston jack is a very efficient method of regulating the yacht mast., however care must be taken when applying the load to avoid damage to the mast and/or boat structure. For large sailing vessels one can say that a mast jack is essential for correct mast regulation.

The maximum load to apply to the piston must not exceed 20% of the maximum load that can be applied to the rigging and should be specified for each vessel by the manufacturer.

Important data to consider when regulating the mast jack.

• area in cm2 of the piston where the pneumatic fluid applies pressure
  (data written on the piston or supplied by the manufacturer)
• on the hydraulic pump there are manometers with two units of pressure measurement: psi or bar
  1 psi = 0.0069 bar, by multiplying the bar by the cylinder section in cm2 we can find the working load in Kg of the piston

There are two separate systems of lifting by mast jack:

• the first with a through rod and two lateral pistons on the sides of the mast connected in paralell to the pump
• the second is a single piston fitted inside the mast connected to a manual pump o connected through a bypass to the vessels centralised hydraulics
• the spacers can vary in height according to the elasticity of the structure and the deformation of the boat. There is no fixed rule apart from good common sense and some testing of different loads to find the ideal tension.

Ensure that the foot of the mast, when resting, touches on all it's perimeter both fore and aft in order to distribute the load uniformly along the profile surface.
If the mast touches only fore or aft , modify the wedge shaped spacers to ensure that the load is evenly distributed.

NEVER USE THE MAST JACK UNDER SAIL BECAUSE THE PISTON LOAD IS COMBINED WITH THE LOAD OF THE MAST UNDER SAIL WITH THE POSSIBILITY THAT THE MAX WORKING LOAD COULD BE SURPASSED WITH POSSIBLE DAMAGE TO THE BOAT STRUCTURE AND MAST.

(possible damage is the collapse of the mast base, breakage of the lande zone, delamination of the strengthened parts used for the attachment of rigging and the like)

Suggestions for the maintenance of the mast:

All masts whether racing or cruising require periodic maintenance.

As with the car which requires engine maintenance every 10000 - 15000 Km, or for planes which require regular maintenance every 30000 h of flying time or 60 months (complete rebuild). Following the same logic every 3-4 years a yacht should be demasted, the rigging disassembled, and all the high load steel parts, pulleys, bolts and other fittings etc. should be checked.

A different system is used for the rigging:

The rigging should be disassembled, all pieces cleaned, and the any oxidisation removed to allow a careful inspection.

The rigging terminals should be carefully checked, it should be in one piece without bends or breakages. It is necessary to check that no strands are broken an that there is no wear on touching parts.

Sometimes this is not enough.

The rigging accessories are subject to various types of wear and tear, many very difficult to identify. Immagine a piece of wire cable which is bent one way and then the other, after a few cycles it breaks. The rigging, if in a different way, is subject to the same principles.

To understand better the problem as a unit of measurement we can take the number of cycles which the terminals can withstand and this depends on various factors: form the use of that piece of rigging to the againg and quality of teh material used in it's construction.

The rigging should be changed if the boat is used continuously for 2 to 3 years or if it is used for two to three months a year for about 10 years.

There are no formula to adhere to or calculations to make, with time the material ages and it's structure can fail without warning.

For spiral bcable and rod we can apply the same principle.

All this is part of the ordinary maintenance that every owner should make for the mast fittings on his vessel. Contact us - info@maxspar.com - and send us as much technical details as possible to allow us to send you an immediate quotation by return.