Alloy round - 11.0 mm (7/16 in) Ø
Details
Alloy round, 11.0 mm (7/16 in) Ø
7075 alloy T6 hardness. 54 grams/metre. Choose length, colour, pre-bend and other work required. Pre-bend can be added to the mast if you wish. And the holes for spreaders, shrouds and forestay can be drilled and sail limit marks applied too.
Although an Imperial size SAILSetc supplies a large number of co-ordinated fittings that work well with this spar material.
It is costly to send full length pieces so consider having several lengths and split the cost with others. It is more economical to send 0.9 metre (or shorter) lengths and masts may be made using joint piece, ref. 17-110. Either add the joiner here or order it from the mast fittings section of this website.
Graphs of 'Stiffness of mast spar material against diameter' and 'Stiffness of mast spar material against weight/metre' are shown in the thumbnail sketches. The suitability of any SAILSetc mast spar material for its intended application can be checked using the graphs shown in the FAQs section - link.
To help add the bend to a mast we have developed a special tool - here.
The mast deflections at the top of the mast with respect to a straight line through the lower section of the mast, and the distance over which the bend is applied, is listed here for your information.
rig | deflection | over upper | |
designer 1 | 1 | 8 | 650 |
2 | 5 | 600 | |
3 | 0 | 550 | |
designer 2 | 1 | 13 | 1060 |
2 | 10 | 840 | |
3 | 10 | 620 | |
designer 3 | 1 | 15 | 600 |
2 | 7 | 400 | |
3 | 0 | 200 | |
designer 4 | 1 | 40 | 1070 |
2 | 25 | 790 | |
3 | 15 | 500 | |
average | 1 | 19 | 845 |
2 | 12 | 658 | |
3 | 6 | 468 |
To help drill accurately aligned holes in the mast spar we have developed mast drill blocks - here.
Guidance on pens suitable for marking difficult surfaces - here.