The rigging experts at Barton Marine, one of the UK’s longest established deck hardware manufacturers, offer some practical advice on carrying out some simple deck and mast hardware maintenance.

Failed blocks and mast sheaves can cause considerably more damage and subsequent cost than just replacing them with new ones. Torn sails, bent spars and even physical damage to the crew are just a few consequences of a block exploding under pressure. Checking your mainsheet traveller and genoa cars for signs of wear and tear is equally important.

Checklist: Blocks and mast sheaves

1. Flush through with fresh water if you have left them exposed to the elements over the winter, you can use a mild detergent to remove mould and mildew, make sure it is ecologically friendly though. Do not oil or grease, this attracts dirt and salt which is abrasive.

2. Check for excessive movement on the bearings of both blocks and sheaves, especially at the mast head. A broken mast sheave invites the halyard to jam itself at the worst possible moment with a trip aloft the only alternative to remove a sail. Barton carries a range of sheave sizes from 30mm up to 70mm diameter or you can contact your mast manufacturer for replacements. If you cannot get the exact same diameter, that’s ok, as long as you make sure your replacement sheave is a tight fit width ways in the mast casing to prevent your mouseline jumping off the sheave and jamming.

How to climb your mast and work aloft safely

3. Check for signs of elongation around the fixing holes and shackles at the head of your blocks. This would suggest overloading. If in any doubt replace it with a higher load block; this especially applies to mast head blocks which are not so easy to inspect.

4. Threaded and drilled shackle pins are a must aloft and should be wire-seized and taped, or even cable tied to prevent unlocking.

5. On the rest of your yacht, look at the condition of your split rings. If they are not tightly coiled then replace with new ones. I always keep a packet handy.

Handy tip is to cover both sides of the split ring with a single piece of electrical or spreader tape and stick it onto itself, this helps prevent snagging in ropes and halyards.

6. For ball-bearing blocks, the sheaves should spin freely. Again flush through with fresh water. Any graunching or uneven spin after flushing would suggest the block has been overloaded. Ball-bearing blocks are not suitable for high static loads, such as round the mast base, replace with a plain bearing block or one with a higher rolling load rating

7. If you are thinking about replacing blocks, there are a number of factors to consider: specification, safe working load and purchase. Always seek professional advice from your chandler or the manufacturer to ensure safe use and ease of control of the sails and rig.

Mainsheet Traveller and Genoa cars

8. To ensure your mainsheet traveller is in tip top condition, rinse thoroughly with a hose pipe and fresh water, especially the underbody where the ball bearings run in the car and along the track. Again you can use a mild detergent solution for stubborn salt deposits as it will not harm the anodising.

9. Take time to look at the end fittings on the traveller. Crash gybes are usually the cause of fractures. Add spare end fittings to your ‘to do’ list. You will need to remove the traveller car to do this so be sure to seek out or source a short length of track to transfer the traveller car onto for repair.

10. Flush through your control line cam cleats with water under pressure. The cams should open and return freely. If not unscrew them and disassemble to check for broken return springs. Worn cam jaws reduce the efficiency of the cleat and will require a new replacement. Go for the highest specification cleat you can afford for a longer life.

11. With genoa cars, check for signs of excessive movement about the sheave bearing. A small amount of play is acceptable but any more than this may cause the sheave to lock up under load. Warning signs are excessive wear to one side of the sheave where it is not rotating. Sheaves can be replaced so long as the car has been regularly flushed through and looked after. Heavy corrosion of the aluminium around the spindle makes it impossible to repair.

How to check your rig while the mast is down over winter

The list of jobs to do may seem endless, but get the important ones over with at the beginning of each season and the remainder can be saved for a sunny day in dock or at anchor!

Thanks to Christian Brewer at Barton Marine

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