Flying 15 Tuning Hints
The following tuning advice has been generously supplied
by Steve Goacher of Goacher Sails, and Alan Bax of Pinnell & Bax.
The measurements are those used on the Mk IX Ovington.
You are strongly advised to make a note of your existing measurements
before you alter anything. If in doubt, consult an expert.
For more detailed information, you may like to consult
ex BIFFA President David McKee's Tuning Guide, which was published in Yachts and Yachting.
Mast Stepping
The position of the mast foot relative to the keel, and
the transom of the boat will vary from model to model. It is not possible
to give a generalised measurement here.
Make sure that the mast is a good firm fit sideways at
deck level. If the mast is loose, then fit packing to stiffen up the
mast. Remember to make sure that any extra packing is applied
symmetrically, otherwise the mast will lean.
The mast also needs to be a firm fit in the mast step.
Again if the mast is loose, it will move around, and this will result in
lost performance.
Make sure that the mast is straight. With the mast in
the boat, and apply rig tension, and then look up the sail track. If the
mast bends off to one side, then ease off the shroud on that side, or
tighten the shroud on the other side, then check again.
Goacher Rig Settings
A full tuning guide is available on the
Goacher Sails website
Spreader Settings
| Mast Type |
Length (A) |
Depth (B) |
| Epsilon |
430mm |
165mm |
| M2 |
430mm |
180mm |
| Nimbus |
430mm |
180mm |
The spreader dimensions given are for boats where the
shrouds are bolted through the gunwales. If the shrouds are bolted to the
hull, then the spreader length will need to be shortened a little.
Rig Tension and Mast Rake
In all conditions, use 24'10½" for the mast rake. This
is measured with the the mast ram/puller released, and the rig tension
set. measurement is from the top black band to the transom.
Assuming 3.0mm Dyform wire, using a Super Spar tension
guage set the rig tension at 28½.
Pinnell & Bax Rig Settings
A full set of tuning guides can be found on the
P&B website
Spreader Settings
| Mast Type |
Length (A) |
Depth (B) |
| M2 |
422mm |
175mm |
| Epsilon |
422 |
197-210mm |
| Nimbus |
422 |
190mm |
| M7 |
422mm |
190mm |
The length of the spreaders will vary from model to
model. The value quoted is for the MkIX, where the shrouds are attached
to U-Bolts outside the sheerline. Older boats such as the Wyche & Coppock
have the shrouds closer in board. In this case shorten the spreaders by
15-20mm.
Rig Tension and Mast Rake
| Wind Speed Kts |
1-4 |
5-10 |
11-15 |
16-20 |
21+ |
| Rake (Metric) |
7550 |
7550 |
7500 |
7440 |
7440 |
| Rake (Imperial) |
24'9" |
24'9" |
24'7" |
24'5" |
24'5" |
| Tension (M2/Epsilon) |
300LBs |
Flat Water Choppy
400LBs 350LBs |
Flat Water Choppy
400LBs 350LBs |
300LBs |
250LBs |
| Tension (M7/Nimbus) |
400LBs |
500LBs |
500LBs |
400LBs |
350LBs |
Mast Rake is measured from the top black band to the top
of the transom on the centre line
The rig tension should be measured using the rig tension at 1 metre above
deck level.
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