When a yacht requests a unstepping quote from RSB we list all the processes and stages involved as we like our customers to be aware of each step involved in setting up and executing the project without problems. For a lot of crews it can frequently look like simply connecting up the lifting slings and giving the crane driver a few signals to start the lift however in the following pieces we will look at what is involved from start to finish.
Today we will look at the steps that are taken with the first stage of the rig removal:
Mast preparation: Before the riggers unstep the mast there are a number of steps that the team follow during the set up procedure. We start by going over any rig plans that are available either onboard or from the mast manufacturers and follow this up by checking through the rig log data that will hopefully give us an idea of what service work has been carried out over the life time of the spar. In the RSB office our team will request a unstepping slot with the yard and specify the cranes we will need and the planned date for the lift.
On the boat a fall arrest line will be set up attached to the top of the mast and one of the team will go aloft and start the measuring, photographing and documenting process. Every bottle screw setting is noted, the prebend is measured at each spreader, a measurement of the mast rake and spreader angles is taken and if the mast is not chocked with Spartite the positioning of the spar in the collar is also noted. Once the measurements are completed the guys will start padding the spreaders and various parts of the rig and forestay/s to protect them during the lift.
On deck the hydraulic hoses are all marked and photographed before being disconnected and capped off and the mast jacks will be set up and tested to make sure they don’t leak under load and to make sure the mast moves freely in the collar in preparation for the lift. Often we find that the mast jacks are left in the salty damp environment in the bilge causing corrosion issues that frequently lead to damaged seals and leaks when under load.
On the larger yachts with very tall and often very heavy masts we frequently look at the various options to lighten up the spar for the lift, these often include removing headstays, radars, Satcom domes, backstay rods and triatic stays to make sure the crane will not have any lifting issues. While the jacks are being tested the rig and standing rigging will be unloaded allowing us to take the opportunity to make sure that the standing rigging pins at deck level are all free and can be removed easily. At this time we will also make sure that the gooseneck pins in the boom and vang are also moving, on the bigger vessels we frequently substitute the original pins for slightly smaller dummy pins that guarantee we will not have any issues removing them when the crane is attached.
Once all this is completed the lifting slings will be positioned on the mast and boom and any securing strops or tag lines will be set up on the spreaders, forestays, backstays and runners to tie them in to the mast during the lift. Any unnecessary halyards and running rigging will also be moused out and secured.
Final checks will be completed by the team to make sure that the electricians have disconnected all cabling, any pipe work or vents are removed and the captain and crew are aware of the plan for the lifting operation and will be on hand to help out if necessary. The cranes and their positioning will be confirmed with the yard the day before the unstep and then its fingers crossed that the weather is kind to us on the big day! On a large yacht or ketch this work can take 4 or 5 days to complete, however as with most jobs proper preparation means an easier, less stressful rig pull on the day.