Selden Furlex Main Type 76, 90 & 108 — Owner's Manual

Furlex Main at a Glance

Discontinued model — documents and spare parts as printed.

A roller-reefing and furling system retro-fitted to existing main and mizzen masts (written primarily for Selden and Kemp masts), based on Furlin masts and Furlex. A light outer extrusion fixed through its flanges and to the mast track carries a tensioned asymmetric luff extrusion with ball bearings at each end; the halyard swivel bearing spreads load over the whole race. The top fitting leads main halyard and topping lift clear of the outer extrusion (the topping lift can serve as a spare halyard), and a second luff groove takes a storm trysail or spare main. Operated by a line from the cockpit or a standard winch handle at the mast.

Check List & Optional Extras

• Basic kit no. 1: basic extrusion (L=2,400mm) with goose-neck fitting and winch; luff extrusion with sail feeder; kicker bracket; bottom fitting; turning block fitting; top fitting; halyard swivel; clew outhaul track and car; outhaul blocks (2); grease; locking adhesive; assembly set; luff extrusion sample; fitting instructions; user's manual.
• Basic kit no. 2: basic outer extrusion and luff extrusion (L = 2000mm), assembly set, outer extrusion sample.
• Extrusion kit: outer extrusion and luff extrusion (L = 2400mm), assembly set.

Preparation & Shaping the Outer Extrusion

• Check the outer extrusion fit with the short sample; if it doesn't fit perfectly, re-form the outer flanges of every length before fitting (use the bent sample as a pattern).
• Boom: check the fit to the boom toggle (drawing: 18mm, w = 20mm, 12mm Ø pin; a 10mm Ø goose-neck pin also works); otherwise the special stainless toggle 528-077 can be modified.
• Halyards: main halyard exits the masthead to starboard, topping lift to port; ideally the main halyard exits to port at deck level.
• Fit with the mast horizontal (supported at three points at least) or stepped with fore and aft stays slackened. The mast must be absolutely straight. Locate internal cables before drilling.
• Tools: 20m steel tape, hacksaw, drill, bits 4.9 or 5mm, 5.3mm and 6.0mm Ø, mandrel max 2.5mm Ø for driving out pop-rivet pins, hammer, Phillips screwdriver with screw retainer.
• Shaping (trained person, bending jig and tool): sail slot as supplied FLX-M 76 and 90: 13,5 +/-3; FLX-M 108: 15,0 +/-3 – don't exceed the tolerances. Recommended maximum bend 25° / 35° as drawn. Too little shaping makes the slot too small for the halyard swivel; too much gives a bad, wavy fit. Always bend the outer (mating) parts of the flanges first.
• Forming set: bending jig with clamps; support batten 45 x 80 x 2200mm; spacer batten FLX-M 76: 14 x 80 x 2200mm, FLX-M 90: 14 x 95 x 2200mm, FLX-M 108: 14 x 111 x 2200mm; aluminium bending tool L = 2200mm. Jigs supplied before 1993 need a larger cut-out for the reefing winch.

Calculating & Cutting the Extrusions

1. Find the lowest position for the basic extrusion with the sample and bottom fitting (bracket turned down on all types, or turned in on types 76 & 90 – then remove the central web of the bottom fitting and fix with M6 x 35 mm machine screws).
2. Mark the lowest point (H1).
3. Measure BTH from H1 to the centre of the horizontal hole in the bottom toggle and enter it in Calculation Table 1.
4. Find the highest position with the extrusion sample and top fitting: the top fitting at least 50mm below the existing top fitting, halyard running freely, backstay clear (average backstay angle 23° to 27°). Mark H2.
5. Measure H1–H2 and enter it in Calculation Table 2.
6. Calculate each extrusion length.
7. Transfer A to the basic extrusion and D to the top extrusion.
8. Cut square (wrap paper tightly round the extrusion as a guide) and de-burr with a fine file.

• Table 1: A = basic extrusion cut length, measured from its bottom edge. Table 2: OXL max outer length − 2200 + A = C + D; C = whole 2200mm extrusions; D = top extrusion. If D is longer than 2000mm cut it from a 2200mm length; between 200 and 2000mm from a 2000mm length; shorter than 200mm, replace the top 2200mm extrusion with a 2000mm one (reduce C and increase D by 200mm).
• Upper luff extrusion cut length = F; it is asymmetric – measure from the bottom edge where the pilot studs are.
• Kicker bracket on types 76 & 80 (as printed): an extension piece below must be over 300mm. Type 108: the internal reinforcement must also be extended (parts from Selden).
• After cutting: drill one Ø6.5 mm hole 50 mm from the end of the basic extrusion (type 108: four Ø6.5 mm holes at 50 mm c/c with Ø15 mm access holes, not in the three lowest reinforcement holes in the sail slot; plug them). A top extrusion shortened by more than 280mm needs a 6.5mm Ø hole in the central groove 50mm from its upper edge, not closer than 50mm to any other hole.

Fitting Furlex Main to the Mast

1. Remove all mast fittings within the extrusion area – but not the spreader brackets (cut the extrusions round them, de-burr).
2. Outer extrusions are fixed with screws and special nuts in the mast luff groove and pop-riveted through the flanges. Where the special nuts don't fit, tap the screws into the groove bottom (mark with a 6-7mm drill, drill 4mm Ø, tap M-5). Older masts with an enlarged groove need the flanges removed and a spacer (e.g. 22 x 26mm teak).
3. Feed the screws with spring-loaded special nuts into the luff groove through the sail feeder – basic extrusion 4 (type 108: 7), each intermediate extrusion 3, top extrusion 3.
4. Basic extrusion first, port outer flange by the luff groove, centred on the mast; fasten with locking adhesive; pop-rivet the outer flanges at four places top and bottom (drill 4.9mm), check the sail slot, then the rest. Knock out all rivet pins.
5. Bottom fitting: types 76 & 90 drill 4.9mm and use the 6-8 pop rivets supplied; type 108 drill 6.4mm and use the 12 pop rivets supplied. Turning block (if used): 6 off 6.4mm pop rivets.
6. Kicker bracket (lowest level, 6.5mm holes): extra fastenings in way of it – types 76 & 90 five 4.9mm holes at 54mm c/c per flange; type 108 eight 4.9mm holes at 27mm c/c plus reinforcement plates 595-692 Stb / 595-692 Prt with 2 x 8 off 4.8mm rivets and 2 x 6 off 4.8mm at the goose-neck reinforcement.
7. Fit the luff extrusion to the basic extrusion: remove the locking sleeve from the tensioning screw, slide it onto the luff extrusion at the sail feeder, and screw the parts together leaving about 15mm (some 50mm) of thread visible.
8. Build upwards per Table 2: pilot pins down, outer extrusion lashed ~0.5m above the previous one while the luff extrusion is joined (joint sleeve down, pop-riveted, pins sealed with the plastic plugs), then lower, fix with three screws, straighten, rivet.
9. Before the upper luff extrusion goes on, drill three 4.9mm holes in its top using the halyard swivel sleeve as a pattern (keep chips out of the bearing). The luff extrusion must end 30 to 40mm shorter than the outer extrusion.
10. Top fitting: halyard on the swivel, swivel down to the tensioning screw, grease the tensioning screw with Furlex grease, rivet the luff extrusion into the swivel sleeve, re-screw, fit the top fitting with four M6 screws (drill 5.3mm, wedge the sail opening), main halyard over the starboard sheave and topping lift to port.

Luff Extrusion Tension & Boom

Correct tension makes furling easy; under sail most of the luff extrusion rests against the aft inner face of the sail chamber.

1. Remove the covers.
2. Undo the locking screw enough to free the locking sleeve.
3. Push the locking sleeve up level with the upper opening and grip it.
4. Turn the tensioning screw with the reefing winch until the sleeve slips in your hand. Or measure force P on a 10" winch handle: types 76 & 90: 12 N; type 108: 20 N.
5. Align so the locking sleeve slides down over the luff extrusion, pull it down to the locking position and fit the lock screw.

Too much luff-extrusion tension risks overloading the system.

• Outhaul track: as far out on the boom as possible (to use the full foot E); use the old outhaul line to lead a new or pilot line. Boom track over 5mm: pre-fit screws and special nuts with locking adhesive (largest M6 hole outside the track). Narrower than 5mm: drill 5.3mm through the track holes and fit the special nuts one by one on foam cushions. Type 108: M6 screws tapped into the boom groove (wall at least 3.2 mm). Check no internal lines can chafe on screw ends.
• Slide the outhaul car from its transport track without dropping any balls; fit the end stop and the smaller block on the car, reeve and tie off the outhaul line. Without internal lines: AL-45 (505-004) or AL-70 (505-006) sheave box, slot fitting "medium" (505-014) and block R-601 (538-900).

Sail Notes

• The luff extrusion is asymmetric to ease the start of furling – avoid heavy cloth in the luff area.
• Head and tack webbing: soft, foldable, 20 mm wide is suitable; no metal cringles.
• Battens on the port side so they don't snag inside the sail chamber.
• Clew cringles no thicker than 14 mm to fit the outhaul block. A clew board gives a longer effective foot than an integrated block or normal cringle.
• The luff curve needs a wedge (0 to 30 mm) at the upper 500–800 mm of the luff. Tack angle 85°–88° as drawn.