Here you'll find all the information you need to rig, tune and measure your AHPC boat. The Associated PDF for each part has more information and images to help you further.
One major problem when comparing boat settings is that each person measures their boat slightly differently, rendering comparison useless. By using these guides you'll be able to accurately compare your boat with someone else on the other side of the world
A number of years ago I heard the following quote applied to catamaran sailing. “It doesn’t matter where you are going as long as you are going there fast.” The element of truth in this statement is that boat speed is ultimately important.
Go fast. Look for pressure then angles; opposite priority compared to dinghies.
AHPC Standard Mast Bend Test
Often we get asked about mast bending characteristics. This is the standard bend test used measure the stiffness of a blank mast
For this test you will require 2 supports, a 20 kg weight and a tape measure.
Remove the diamond wires from the diamond arms.
"Sideways"
1. Space the 2 support exactly the correct distance apart (TAIPAN/VIPER - 8400mm, CAPRICORN/C2 - 8840mm)
2. Lay the mast on its side on the supports
3. At the midpoint between the supports, place a 20 kg weight on the mast and measure its deflection downwards
"Fore-aft"
1. Space the 2 support exactly the correct distance apart (TAIPAN/VIPER - 8400mm, CAPRICORN/C2 - 8840mm)
2. Lay the mast on the supports with the sail track pointing UP
3. At the mid point between the supports, place a 20 kg weight on the mast and measure its deflection downwards
NOTE: Please check the mast for fore aft straightness.
Note any permanent bend in the mast as this will affect the required luff curve in the sail
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Diamond Measurement
Diamond tension:
The tension on the diamond wires primarily controls the side bends of your mast. Loose diamonds allow the middle of the mast to bend to leeward and the top of the mast to hook to windward. This tends to cause the boat to heel very easily in wind gusts. Very tight diamonds do the opposite. Downwind, tight diamonds keep the mast bent reducing camber and power.
Measuring diamond tension is done with a loose gauge. As there are a few types of gauges, simply follow the instructions on the specific loose gauge to get your diamond tension.
Make sure the mast is NOT on it's side as this will load one side of the diamond wires and relax the other Giving uneven results.
Be sure you measure the tension as far away from turnbuckles and fitting as possible as they will affect your reading.
Spreader Rake
Spreader rake is a method of tuning the fore-aft stiffness of a mast below the hound (fixing point of stays and trapeze). The ideal amount of spreader rake is depending on the fore-aft stiffness of the mast and to a lesser extent the amount of luff curve cut into the sail. Generally:
-Stiff masts require more spreader rake to bend the mast sufficiently.
-A soft mast requires less spreader rake.
-If you have excellent height, but lack boat speed upwind and the boat does not want accelerate in a gust, more spreader rake is needed. This helps the mast to bend fore and aft, allowing the sail to flatten and the leech to open in the gusts.
Spreader rake can is measured by stringing a line between the diamond wires at the spreader tip and measuring the distance to the sail track (See Pic1).
When adjusting your spreader rake you should check that each side is even by measuring from the sail track to the wire (See Pic2). MAKE SURE THE SPREADERS ARE PERPENDICULAR (90deg) TO THE MAST BEROFRE SAILING.
Pic 1
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Pic 2
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Mast Rake
Using the forward trapeze wire the distance to the attachment point of the forestay in the hull is measured (trapeze has to be extended with a rope) (Pic1). This distance is than taken to the stern of the boat, the position on the transom is your mast rake measurement (Pic2). Releasing the shock cord will make this process easier.
Generally speaking light crews should carry more rake and heavy crews should sail with slightly less mast rake.
Pic1
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Pic2
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Raising and Lowering your Mast
The usual procedure is to raise the mast from the back of the boat however, the hinged mast step allows the mast to be raised and lowered from any direction. Raising the mast requires a minimum of 2 people. The usual procedure would be:
Raising The Mast
- Put the assembled platform on a flat surface, preferably with its sterns windward.
- Position the mast on the boat, sail track down, with the base of the mast just forward of the main beam and the top of the mast out the stern.
- Connect the side stays to the corresponding chain plates, with the Staymasters adjusters at maximum length.
- Keep the trapeze wires loose and untangled.
- Turn the mast over, sail track up, and connect the base of the mast to the mast step using the hinge pin trough the aligned holes of both mast base and mast step.
- The 1st person walks the mast up from the stern as the 2nd person pulls the mast up using one of the trapeze wires.
- When the mast is vertical allow the mast to rotate so that sail track faces backwards.
- The 2nd person should hold the mast upright with one of the trapeze wires while the forestay is connected.
- Set the front stay to the appropriate setting
- Adjust the Staymasters to tighten the rig properly.
- Take out the hinge pin from the mast step.
Lowering the mast
This is basically the reverse as raising the mast:
- Remove the boom and spinnaker pole
- Put the mast step hinge pin in place
- Lessen the tension on the side stays.
- Undo at least on trapeze wire.
- Use that trapeze wire to pull the mast forward, releasing pressure on the pin at the forestay, disconnect the forestay.
- Turn the mast around so that the sail track is facing forward
- Gently ease the trapeze wire to slacken the side stays. The second person should stand on the trampoline to lower the mast down, since at a certain point the mast cannot be held by the trapeze wire alone. Be careful not to drop the mast on the track of the rear beam.
Pictures coming soon
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Sailing with the ProWing Mast
This type of rig offers many performance advantages compared to a "Pear" section mast, such as better boat speed, better pointing ability and more sophisticated sail control. The end result is a faster boat which is easier to sail.
The Basic Concept
The idea is to effectively make the mast part of the sail; to do this the Leeward side of the mast is faired into the shape of the sail. You will notice that your sail has an extra set of telltales down the luff. These are to indicate if you have the correct amount of mast rotation compared to the sail. A good starting point is with the leeward telltale streaming freely and the windward telltales stalling intermittently. All the other telltales on the sail should still flow freely.
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Rudder Alignment
Correctly aligning the rudders will have a marked effect on the feel and performance of the boat. The simplest method is to support the boat so that the rudders can be put in the fully down position. Use a tape measure to measure the distance between the leading and trailing edges of the blades at the bottom of the transom. The rudders need to be set up so that they have 2 - 4mm of toe-in; that is the leading edges of the blades are 2 – 4mm closer together.
To adjust the alignment, unscrew the small screws that hold in the tiller cross bar ends and slide the white nylon spacer in or out and desired. DO NOT slide the rubber flex joint out of the nylon spacer. You will need to drill a small pilot hole into the nylon so you can re-screw the small screws back into the ends.
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Lock Down Rudder System
The AHPC Lock down rudder system is a unique system that locks your rudders up or down. In the lock down position the rudders are fixed and will have no movement in the stock, however they will release if you run aground only causing minimal damage to you rudder blade.
Lock Down:
Lift the rod pin out of the forward hole, use the rod to push the blade down. Press the rod pin into the aft hole. Your rudder is down!!
Lock Up:
Lift the rod pin out of the aft hole and use the rod to pull the blade up. Push the rod pin into the forward hole, the PVC catch will lock it in place.
If you having trouble lifting the rod out of either holes, grip the middle of the rod and lift there.
Adjustments:
The lock down rod should have a small bow in it when the blade is locked down. These will be preset from the factory, however, should you need to adjust them, simple loosen off the lock nut and wind the rod in or out as desired.
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Tying in Foam Battens
We are often asked the best way to tie in foam battens as they have no "V-lock" ends on them.
- The tie-in strings should be tied through the bottom eyelet with both ends of tie-in string the same length.
- Pass both strings through end of batten, then down through top eyelet.
- Separate tie-in ends, one each side.
- Tie half hitch around the tie-in string snugly against the top eyelet.
- Adjust the batten tension using your thumb to push the batten in as you pull on the ends of the string tie-ins.
- The half hitch will hold the batten tension at the selected pressure.
- Complete the knot by tying another half hitch to complete the reef knot.
** To prolong the life of you sail, release the pressure from your battens before storing.**
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Pic2 |
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