FOR TOTAL PERFORMANCE – & FOR ANY BOAT

1.  What is involved?
a) For each seat in the boat, measure & record 5 simple "lengths" – for letters B, C1, C2, F & G on the rigging form
b) For each rigger, measure 4 simple "lengths" – D1, D2, D3 & E
c) For each rigger, measure one "angle" – A on the form

2.  What is critical?
a) "Lengths" – be careful and rigorous. Measure to nearest millimetre or 1/16 inch, particularly for D1, D2 & D3. Show your units of measure. Double check measurements – we cannot accept responsibility for your errors.
b) "Angles" – accurate measurement of angle A is most important – a 1 degree error gives a 1cm height error.

3.  How do I measure Sax Bevel, A?
You need no fancy instruments. Just a short straight-edged board, a sharp pencil, a piece of paper, some sticky tape, a straight ruler or stick, care and a "third hand".
Do it like this:
Take off the riggers. Stand the board at right-angles across the boat, at the main rigger shoulders and on its straight edge, like this:

(holding the board upright and steady is the job for the "third hand"!)

Place the ruler vertically against the outside face of the saxboard, next to the main rigger bolts, so that it also lies flat across the face of the board.

Then, with care, rule a line on the face of the board along the edge of the ruler. Mark that line with the seat number and the side of the boat (don't forget this!). To keep it simple we didn't mention the sheet of paper. But lines ruled on a board are less handy than lines on paper. So, before starting, tape the paper tightly onto the board, wrapping its lower edge around the bottom edge. And do not forget to mark that bottom edge onto the paper. Mark the sax bevels for every rigger position (they often vary from side to side and along the boat). Send us the sheet of paper with your completed specification sheet. We will pick off the A values ourselves. If you want to fax us the paper with the sax bevel marks, then please remember that faxes slip & stretch in transmission: first you must accurately mark it with a pair of perpendicular lines with precise scale markings – or use squared paper (eg graph) – so that we can re-scale.

4.  Why measure the rise, E, when what I want is a work height off the seat?
We at CDRS don't know where the seat or seats are in your boat. Rigger makers work from a single "datum point" – the top of the sax at the main rigger shoulder. The rise, E, is the vertical distance of the lower pulling corner of the gate above this datum point. The "work height" is the rise, E, plus the distance from the datum point down to the seat. If you prefer, give us a clearly indicated "work height", instead of E, but then you must also tell us how far the seat is below the top of the sax. By all means send us a dimensions sketch.

5.  Where can snags arise?
a) The Saxboard is "cut down" at the Aft Shoulder.

People sometimes give C2 & D3 measurements without telling us that the sax level from which they are measuring is not the same as at the main shoulder. If we don't spot the error the aft stay will go to a non-existent D3 bolt position, perhaps even missing saxboard!

This affects many sculling boats. So do note on the specification sheet if the sax at C2/D3 is cut down and tell us by how much it is cut down. To do this, rule a straight line along the saxboard at the main shoulder position but at the cut down level; then give us the distance (down the face of the sax) from the highest point of the sax to this line. We can make all necessary corrections to C2 & D3.

b) The Saxboard has a projecting Lip.
This means you can't directly measure the sax bevel, A, and that all the C1/C2 measurements are too large – by twice the width of the lip. If the lip is very pronounced it may also affect how we have to make the riggers. Please always tell us if there is an external lip on the top of the saxboard. When measuring for A you now, additionally, need a small parallel-faced block (held by a fourth hand!) to go between the saxboard and the ruler so that the ruler clears the sax lip. And, please, tell us how far the lip projects horizontally beyond the face of the saxboard. We can then make the appropriate corrections to C1/C2.

c) The face of the Saxboard, against which the rigger bolts, is not flat.
Here the best you can do is to try to rule the sax bevel line at what appears to be the best average angle for that position.

d) The Hull curves away from the Saxboard very close to, or at, the D2 position.
Normally the flat face of an AeRoWing rigger foot extends about 15mm (5/8") below the D2 bolt. If this would cause it to indent the curve of the hull, please tell us where the hull curve starts in relation to D2, and we will alter the foot to suit.

6.  Topstays
Not needed for sculling – rowing only. Two measurements required, the topstay stateroom and topstay bolt spacing, b and d on the rigging form. Topstay is drilled with 8mm diameter for attachment at swivel pin, to match our AxioR pin, so if ordering topstays for other than AeRoWing please advise if larger hole is required.

7.  Any other problems?
Rigger measurement is normally straightforward. If there is anything you don't quite understand, or that gives you grief, please call us for further advice. We want you totally satisfied with your new AeRoWings – advice is free, riggers cost a bit more!

Specify them on your boat – you have the right!

To make life easy use our form to fill in your measurements and order our riggers.

  Printed version of these instructions

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