Official rigging specifications for Selden Cumulus & Superspar M7 masts
Crew Weight: 21-24 Stone | Mast Manufacturer Specifications
Premium mast system with proven performance characteristics
High-performance racing mast with optimized bend characteristics
Same settings for both Selden Cumulus and Superspar M7
375mm
155mm
Measurement Note: Spreader length (A) is the total horizontal span. Spreader angle (B) is the perpendicular deflection from the mast centerline.
Mast heel as far aft in the step as possible
Maximum aft position
Measure from aft point on transom centerline to aft bolt on mast step
2840mm
Precise measurement required
Series 11 Note: You may need to measure through the transom flaps to reach the aft point on the centerline.
| Conditions | Mast Rake | Rig Tension |
|---|---|---|
| Light | - | 400 lbs |
| Medium | 21'9½" - 10" | 400 lbs |
| Heavy | - | 350 - 400 lbs |
Measure from top of mast to top of transom
Measure with rig tension on (400 lbs)
Find datum point: measure to top of gooseneck (18"), then swing tape to transom
After achieving rake, measure pre-bend: 5mm bend at spreader height
Base setting: 400 lbs for most conditions
As wind increases: Add more rig tension until overpowered
When overpowered: Begin reducing tension back to 350-400 lbs range
Fairleads from centreline - Middle of deck
1 hole aft
From base position
2 holes aft
From base position
Purpose: Moving fairleads aft opens the upper leach of the sail, preventing the slot from choking in stronger winds.
Pinnell & Bax Mast Setup - Key Numbers
Spreader Length
375mm
Spreader Angle
155mm
Mast Position (Mk2)
2840mm
Base Rig Tension
400 lbs
Mast Rake (Medium)
21'9½"-10"
Pre-bend Target
5mm
Pinnell & Bax are renowned sailmakers and rigging specialists with decades of experience in dinghy racing. Their tuning guides represent the collective knowledge of champion sailors and their expertise in optimizing boat performance.