INSTRUCTIONS
Hole layout, location relative to the I-point and the fitting procedure for the Selden Triple Combi forestay boxes 505-011-01 and 505-018-01/-03.
DocumentSelden Forestay Box Type Triple Combi Instructions
FormatPDF · 1 page · 0.5 MB
LanguageEnglish

Forestay Box Type Triple Combi
Discontinued model – documents and spare parts as printed.
| Part No. | Forestay | Hole layout (centre distances, not to scale) | Fasteners |
|---|---|---|---|
| 505-011-01 | Ø 4/5 mm | Ø 7 – 21 mm – Ø 22 – 131 mm – Ø 22 – 21 mm – Ø 7 | 2 pop rivets LD870 (Ø 6.4 x 17.8), included |
| 505-018-01 / 505-018-03 | Ø7 mm / Ø6 mm | Ø 9 mm – 33 mm – Ø 40 mm – 180 mm – Ø 40 mm – 29.6 mm – Ø 9 mm | 2 screws MRT 8 x 25 (round, Torx head), included |
- Location: the upper large hole sits above the I-point (ISP): 12 mm for 505-011-01 (Ø 22mm hole), 15 mm for 505-018 (Ø 40 mm hole).
- Tools: pencil, ruler, drill, Ø 5.0 mm drill bit, hole saw (Ø 22 mm or Ø 40 mm), jigsaw, half round file; plus Ø 7.0 mm bit, pop rivet gun, Ø 2.5 mm mandrel and hammer (505-011) or Ø 9.0 mm bit and Torx screwdriver (505-018).
Fitting Procedure
- On the front line of the mast, mark and pre-drill all 4 holes with the Ø 5.0 mm bit.
- Open the top and bottom holes to Ø 7.0 mm (505-011) or Ø 9.0 mm (505-018).
- Open the two intermediate holes with the hole saw (Ø 22mm or Ø 40 mm).
- Draw straight lines between the large holes, one each side, touching their edges; check the distance equals the fitting width.
- Saw along the inner edges of the lines so the slot is as wide as the fitting.
- File the slot edges smooth, without notches.
- Check the fit: insert the box, pull it against the front of the mast until it rests on the inner mast surface above and below the slot; it must rest on the mast wall at its lower end. File if needed.
- Remove the box, feed the genoa and spinnaker halyards (or messengers) and reinsert it.
- 505-011: check it rests on the inner surface, pull the two pop rivets and knock out remaining mandrels. 505-018: lubricate the screws and tighten carefully without deforming the mast wall.
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