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www.neilpryde.com/collections/sails-2021/products/rs-racing-evoxii



QUADRUPLE LUFF PANEL LAYOUT

The EVOXII features four continuous, durable, stretch-resistant and lightweight luff panels that carry most of the sail's body shaping. This configuration stabilizes the critical section draft position while providing an increased film thickness proportional to the downhaul load distribution.
Continuous panels eliminate horizontal seams crossing the highly loaded leading edge, which increases response of the sail.

Today all sail models are made from continous panels (one piece of monofilm) and what if one broke,do I need replace all sail panels area?
Was RS slalom also made from continuos panels?

not Aerotech sails, they do not have monofilm and are made of multiple panels like most modern sails, I think.

No and no.
and I don't know why some think the seams and joins are the weak points, if done right their stronger

That does not say the sail is one piece of mono, it refers only to the luff. They are all made of multiple panels.

IF it was one piece and you tore one bit, you would only replace one panel by cutting along the batten seam, glue(tape) and sew new piece in.

I gather from all these questions you are wishing to try making sails? There is a LOT to it so I recommend going to a sailmaker and watching them repair a WS sail. The setup needed and the machine needed is quite a large undertaking. Maybe send a message here to the guy in Turkey (?) who makes his own. " Melih " I think........ ?

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hotlap said..

www.neilpryde.com/collections/sails-2021/products/rs-racing-evoxii



QUADRUPLE LUFF PANEL LAYOUT

The EVOXII features four continuous, durable, stretch-resistant and lightweight luff panels that carry most of the sail's body shaping. This configuration stabilizes the critical section draft position while providing an increased film thickness proportional to the downhaul load distribution.
Continuous panels eliminate horizontal seams crossing the highly loaded leading edge, which increases response of the sail.

Today all sail models are made from continous panels (one piece of monofilm) and what if one broke,do I need replace all sail panels area?
Was RS slalom also made from continuos panels?

Those sails do not look like they are made from 'continuous panels'. There are obvious seams.
A panel failure can be repaired as normal with matching mono film, but the real issue here is that the upper panels have painted graphics which would not be replicated.
The window would not be a problem.
The foot panels would need a match for the material used.

There is no such thing as a continuous panelled sail.

North sails 3DL are probably the nearest thing but they still use panels that are stuck together on a moulded surface, then a continuous fibre is laid from head to tack / clew etc, then more panels laid on top of that and then baked to set the glue.

Membrane sails still have panels, usually joined at the batten pockets, this is where the sails gets its shape.

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Madge said..
There is no such thing as a continuous panelled sail.

North sails 3DL are probably the nearest thing but they still use panels that are stuck together on a moulded surface, then a continuous fibre is laid from head to tack / clew etc, then more panels laid on top of that and then baked to set the glue.

Membrane sails still have panels, usually joined at the batten pockets, this is where the sails gets its shape.

So this part that I marked is not made from one piece,between every two battens is on panel that is seamed to adjacent panel etc?

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Ben1973 said..
No and no.
and I don't know why some think the seams and joins are the weak points, if done right their stronger

You are Ben Severne?

No that is not one piece...... for the same reason as your other (many) threads you started - it needs seam shaping so it has shape. Monofilm does not stretch so you can't make a nice airfoil shape without having panels with curved edges sewn together

From Ezzy site: A sail shaped with excess luff curve has more luff curve than the curve of the mast after being rigged. This forms a cavity next to the mast, which, in the case of a full batten sail, becomes batten rotation. The problem with sails shaped with ONLY this method is that in strong winds, the mast bends more, which removes the shape from the front of the sail.
Sewing panels together that have curved seams achieves panel shaping. Once the panels are together, they assume a predetermined aerodynamic profile. Panel shaping when used in conjunction with excess luff shaping produces a more stable sail profile. Panel shaping can be vertical or horizontal. Horizontal shaping is usually under the battens and is a better shaping method than vertical shaping because it controls the shape from luff to leech.

Anyway..... what are you trying to do? Make a sail?

No this again, the body of this sail is at lease 9 pieces of sail material.

This part of the add even tells you the body is made of different panels, and it the only way to do these batten pockets.

Plus the fact sail clothe comes on rolls in set widths and it's not wide enough for a sail

I think the breakdown photo of the panelling is quite interesting here.
A camber-induced sail is obviously more complex than a basic rotational sail design. Both sails still need to set with maximum sail fullness at some point one third back from the mast - although the upper sections of any windsurf sail tend to be flatter, and they set with twist.

In this case, the coloured (painted) section of the main panel could indeed be one flat piece, with the batten pockets then sewn over the top.
I would suspect however there is a seam between the window and that upper panel, with the seam covered by another batten pocket.

Sails do need some broadseaming to ensure reliable shape in the front sections of the sail but the seaming can be vertical as well as horizontal, and with a twin luff sail that shape can be added in the many vertical seams shown in that graphic. The twin luff structure itself does guarantee and front biased aerofoil shape.
And for the rear half or rear two thirds of the sail we do need the sail to set flat or flatter.


Our bigger light wind rigs are often made to set a lot fuller than the typical rotational sail, and they notably have double curvature* in the lower sections, whereas small rotational wave sails generally don't.
To get double curvature you definitely need seaming - in the same way that your jeans are cut to fit around your arse. (Whereas the legs of your trousers are just two tubes of material, cut with simpler seaming because we only need single curvature.)

*Single curvature means you can set a straight line along the panel in at least one direction. With double curvature, you can't.

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hotlap said..
Today all sail models are made from continous panels (one piece of monofilm) and what if one broke,do I need replace all sail panels area?
Was RS slalom also made from continuos panels?

I looked it up. They dont list 2020 or 2021 sails, but the 2019 sail was made up of different panels as listed in the spare parts manual.
I suspect current versions are the same, different thicknesses and weights of material in different areas.

cdn.shopify.com/s/files/1/2119/3655/files/2019_EVOX_10.0_fc93be85-48aa-4022-abfb-d9d63c717d82.pdf?7517

www.neilpryde.com/pages/manuals