Hi again lkw,
To better answer your question, there is a mast slot in the top of your board with
a wider access slot at the back.
You need a twist on mast base, with a brass "T" nut.
The "T" nut goes down in the slot, slides forward a bit, and you tighten it down with the
twist plate on the mast base. The screw on the bottom of the mast base pulls/clamps the
brass "T" nut up in the slot to lock your mast base in position.
Try to get a mast base that is "on center"! They cost a bit more than the off center mast bases,
but they tend to be more strongly made and do not come loose and slide around like the
off center bases (incorrectly shimmed).
You will probably need a short (15 cm) mast extension to engage with the top of the
You will most likely need a 400-430 cm mast (buy the highest carbon content you can afford here).
Try to avoid buying a 460 cm IMCS 25 mast and extending the head cap on the sail as this will add alot of weight to your rig, at the wrong end of the lever.
Also, the IMCS (Indexed Mast Check System) for your 4.7 sail will be 18-23 and a 460 cm mast will have an IMCS of 25 so the mast will not bend correctly in your sail.
Hope this helps,
Last edited by Roger; 19th June 2010 at 12:24 AM.