Most In-Mast Furling Systems have a built-in Spare Luff Groove in the extrusion, for a backup mainsail or staysail.
Some do not, but we can still offer a solution.
Usually, when there's an integral Spare Luff Groove, identifying sail slides for it is relatively straight forward. We can either go from measurements and photographs, or by identifying the manufacturer and model of mast. If in doubt we'll send you some sail slides to test.
Measurements will ideally be of the groove in section, which can best be seen at its gate. Alternatively, to track down dimensions and profile from manufacturers, we'll need as much information as possible, such as year of manufacture and if possible, serial number. Some makes have their serial numbers engraved low down on the starboard side.
Some Spare Luff Grooves, being intended to take luff tape, are smaller than any sail slides that are generally available. Selden R Sections 190/94, 213/104, 235/116 and F Sections F176, F194 are examples of this. We now make R5.2 slides, suitable for ladders, to fit these Spare Luff Grooves. A small additional charge of £3.30 per metre of ladder is applicable if these are required.
