Cam Rotation

Hi
In this message I will discuss the problem of cam rotation and hopefully, provide some solutions.  In the previous post I mentioned Martin Cross and the problems he experienced with his new Overdrive.  He has just upgraded his Turbo for an Overdrive and where the Turbo rotated beautifully, the Overdrive sticks on the top two cams.

To save a lot of writing here is a copy of the e-mail I sent Martin:

Hi Martin

You are right about this being a common problem and I need to write a post covering this aspect of camber induced sail rigging.  My experience in this area has taught me to follow these steps to effect proper rotation of sticky cams. (Please forgive the rambling explanation):

     

 1. Ensure that if the inducer is an asymmetrical one, that it has been installed the right way up.         Sometimes the factory gets this wrong.  Just look at  how the cam sits on the mast.  If it is being pulled unnaturally, try rotating it and see how that works.  If the inducer is symmetrical - no problem.

 2. Give a bit more downhaul and see if this improves things. 

 3. Ensure that the cams are not getting snagged on loose protective tape (which Severne used on older masts).  This tape is quite soft and can distort and  bunch up where the cams make contact.  If the tape is snagging things - cut loose bits off and sand the area down. 

If the above measures fail, you are going to need to file the curved section of the cam down slightly.  This is the section which comes into contact with the batten pocket (NOT THE MAST!).  You will need a circular cross sectioned file (we call them rat-tail files).  Make a mark about 1mil from the existing curve edge and file the opening down until you reach your mark.  You are aiming to bring the cam away from the mast by enlarging this space.  The concave form runs the width of the cam of course so make an identical felt tip pen mark on either side of the cam and file down carefully until you reach both marks.  This can be a fairly long process as you shave the surface down, rig the sail and test the rotation. Repeat until the cam rotates nicely.  If you get one cam working properly it may just pull the other one round as it rotates but if not, then you need to repeat the process with the other cam.

The photo attachment indicates the cam surface I am talking about.  This is what you need to file down.

Please let me know how you get on

Here is the picture I attached to the mail:

Martin says that he is not that keen to start hacking away at his pristine new sail and I have to say that I understand this.  Cam filing should only be done as a last resort.

In a follow up e-mail, Martin mentioned something which caused my ears to prick up.  He said that he noticed when he de-rigged, that the bottom of one of the cams had gouged the mast (obviously as it rotated).  This opens up a really important further measure which I had not mentioned.  When you do your final downhaul after snapping the cams onto the mast, it is possible for the upward movement of the mast and downward movement of the sail to result in one or more cams being pulled out of alignment.  When this happens it compromises the cam's performance - the rollers do not sit squarely and so cannot do their job.  This can have two effects - firstly the cam in question does not rotate, secondly the adjacent cam can be prevented from rotating because it's mate is locked.  You then assume that both cams are faulty.  Wrong diagnosis!  Further, if one of your cams does settle in a missaligned position and you then force it round by kicking, head butting or punching (we've all been there), then what you get is a weakening and stretching at the cam/batten interface.  This can cause the cam to default to the incorrect position every time you rig and you can be left labeling your sail as "that damn thing which doesn't rotate".

The upshot of all this is - please ensure that all of your cams sit squarely on the mast before you hit the water.  This is really important for new sails.  You may just need to pull the cam slightly into the correct alignment to free it up.  This is crucial if you have one of the older red Enigma masts.  The protective tape on these masts is quite tacky and can easily snag your cams.

I hope that this post is useful.
Good winds
       

Session Notes and Some Reader Feedback

Hi

We had some reasonable wind a while ago and I witnessed some really good performance from what I had thought was so-so kit.  The wind was not up to full strength and was still quite gusty.  In these conditions I sometimes take out my Cross 6.4 on a big slalom board (124l).  The board is super light and planes easily so the unlikely combo works fine until the wind picks up and I can change the board for our 116 3S and have some real fun.  The significant thing about the first combination is that it is unexpectedly fast and has the ability to spank serious equipment if the other rider is not top notch.

Anyway, Julian Field - a good sailor from Cape Town was on the water with his brand new 8.5 Phantom on a 79 Speedster with Z Fin .  He seemed to be going really well so I joined him for a few runs thinking that I would be able to run away from him.  No such luck!  I could almost hang with him but he was faster.  Jules is a good sailor as I said but I have never seen him going this fast.  The new 2 cam Phantom is absolutely awesome.  He had it pulled right down almost collapsing it and the result was some proper performance.  I am ambivalent about the 2013 Phantom ( 3 Cam) - it is too hard and racy for me but this new model seems soft, easy and very, very fast.  Jules has the old gold 100% mast.  The complete rig felt pretty heavy on the beach but we know that these are heavy sails, the masts are heavy too and his Pryde X9 boom is pretty chunky so no lightness anywhere but Jules recons that once on the water the thing is feather light in the hands.

Following on from this, Martin Cross - a reader, e-mailed me about his new Severne Overdrive.  Once he managed to rotate the cams he says that the sail was fantastic - light, easy and fast.  These two instances give me hope that the manufacturers are finally getting the message and creating some properly soft but properly fast performance sails.  Next season is starting to look good on the sail front.

Martin's problem was with the rotation on the new Overdrive and he suggested that I do a post about this problem and discuss some remedies.  This is a good idea since the rotation of cammed sails gives so many of you problems.  I will discuss Martin's actual problem in the next post, what I suggested and some of my thoughts on his case and the issue in general.

Talk to you soon  

    

The 7.8m Sail Question and Some Reader Feedback

Hi
Sorry for the long break.  A while ago Joos asked me for some suggestions about what to replace his 7.8m Severne Reflex with.  My current view is that for most of us, pure race sails are the wrong thing.  Depending on your brand loyalties, availability in your country, what your favorite supplier stocks etc - here are the models I would choose from:

• Ezzy Lion 7.5  
• North S-Type 7.8
• Hot Sails Maui GP2 8.0
• Maui Sails Titan GSX 7.5
• Severne Turbo 7.5
• Severne Overdrive 7.8
• Avanti Condor 8.2
• Ka Koncept 7.5

Since Joos is a Severne man through and through, my suggestion to him was the Turbo or the Overdrive.  Joos is not overly concerned with being the fastest guy on the water so he has opted for the Turbo 7.5.  A fine choice which will provide the low end power he needs on light days but also give a fairly wide window for when the wind picks up.  All of this comes in a super light package which should be light in the hands and easy on the body!  Personally I would have opted for the Overdrive for its extra performance.  I have always been against the Overdrive for being too racy but the latest pictures and the video of Sean blasting so easily along has changed my mind.  Severne has also made the sail compatible with both SDM and RDM masts showing that they understand the need most of us have for a softer performance sail.

Overdrive

Turbo

I'm not too keen on the overhanging batten at the boom on both of these sails.  I'm also not keen on the fancy batten tensioners on the Overdrive but these things would not stop me buying either of these machines.  I await Joos's new sails (he has also ordered a Turbo 6.5) and will report back if I can scrounge a ride.

Reader Feedback

Kevin Do tells me that he rode one of the new Hot Sails Maui GPX sails and he recons that this thing smokes.  Kevin is a Ka Koncept rider so he knows what a fast sail is.  I have to say that when the GPX was announced it just looked right to me - simple, light and beautifully made.  I'm not sure how it would stand up against the Crosses in high wind but I think that it would do just fine.

   

Davide Verotta, a sailor from San Francisco commenting on the post regarding safety, says that a few of the San Francisco locals sail with VHF radios.  This is a really good idea because it enables you to communicate immediately with your mates and let everyone know what the problem is.  They can then organize among themselves what is to be done, who will do what etc.  Everyone is immediately and constantly in the loop and the situation can be resolved quickly.  The new water resistant radios are small and powerful.  What a great precaution!

On the new equipment front, I note that the new GA (Gaastra) masts are about to break cover.  The 100% carbon masts are dark blue now.  Look out for them soon.  We need to know whether the bend characteristics have changed.

OK - talk to you soon.  The wind outside looks quite good for this time of year so I am off for a sail. 

   

Some Thoughts About Manufacture in Windsurfing

Hi

Before I deal with the 7.8m sail question, here is a technical post looking at the future of manufacture in our sport.  

The way boards and fins are manufactured has not changed since modern surf boards were made back in the 60’s.  Anyone looking around at modern developments in manufacture has to be questioning the way our industry continues to operate.  Despite the appearance of high tech scanners, 3D printing, unbelievably strong and light composites, we continue to design and manufacture fins, boards, masts and sails using the same methods used at the birth of windsurfing.

The business model has also become obsolete.  Take boards for example – a model is designed, tested and finalised.  The dimensions and material specs are then given to a central factory where the board starts off as a milled foam blank, composite and carbon fibre layers are applied using vacuum packing, heat, pressure and finally, labour intensive hand blocking to approximate specified shapes and dimensions.  The finished board is then shipped to a foreign country to be sold.

                               

What should happen in a modern world is that the approved design is scanned into a file which can be e-mailed anywhere.  The file is used to produce the board where it is needed.  3D printing makes this possible.  The sticking point for me has always been that you cannot print with carbon fibre.  Without carbon fibre I am not happy.  Well a guy called Greg Mark has invented a method of printing with carbon fibre and with his team, has produced a printer to do this.  Yay!

 

Control/Click on the link below:

 https://www.youtube.com/watch?feature=player_embedded&v=Y5wjjDBdgeE

Their initial printer looks too small to print a whole board but the technology has been nailed so upscaling should be easy.  Just imagine being able to print off a few fins from your desk.  With this technology each fin will be exactly the same as the original, providing the recipe used is exactly the same.  You could have one shape with a few recipes - each giving a range of bend/twist/stiffness ratings.  Download the file and print the fins of your choice.  Awesome!

The moral dilemma around all of this is ensuring that designers get paid for their designs.  We have to retain the great designers and developers of our sport and will only do so if they can prosper within a new order.   Windsurfing without the likes of Kashy, Fagerholm, Vollenweider, Green, Zajicek, Spannier, Ezzy, Wentzel  etc, etc, etc would be very sad indeed.

Some food for thought

Talk to you soon         

"Rocket" Advert

Hi

This is a very short post.

Kevin Do drew my attention to a page on Starboard's site which refers to two tests on two of their models - Futura and Carve.  The wording on the picture refers to the Futura being a "real rocket" and this is simply a quote from the test result.  The way they have structured the illustration though, is definitely a dig at Tabou's Rocket and one can easily understand the thing to mean "The Real Rocket".


Very subversive, very clever and good for a chuckle.  Nice one Starboard!

Our season seems to be officially ending today.  Windguru shows no more sailable wind for the forseeable future.  Very bad

The next post will either be a piece on gybing or some commentary about the 7.8m sail dilemma for the normal sailor and how Joos has addressed this when choosing a replacement for his Severne Reflex.

Good winds

2014 Tabou Manta 71 - Some Advice from Ben

Hi

I promised to share some information on setting up the Manta 71.  The background to this is that Anthony (our supplier), sent Ross Williams an e-mail asking for advice on this topic.  Ross forwarded the e-mail to Ben vd Steen who replied thus:

From: Ben van der Steen
Sent: 17 March 2014 11:08
To: Ross Williams
Cc: cedric bordes; antony@capesport.co.za
Subject: Re: 2014 Manta 71

Hello Guys,

I have been using the 71 a fair bit now and it does not seem to need very big fins 

40/39  on 8.6

39/38 on 7.8

38/37 on 7.1 

so Antony your fins are for sure a bit big . You can also try the mast track a little more forward if you keep tail walking .

The footstrap position on the board is also a bit closer together than previous years so you might want to put you straps little more apart .

I personally use the back strap 1 hole from the back and front one all the way forward or 1 from the front.

  

so try the smaller fins play with the masttrack a bit and let us know how it goes

Best regards
Ben van der Steen

This is interesting because it ties in with what several guys have been finding regarding fins for the 71. Charl changed fins from a 39 VMax to a 37 S11 and tells me that he immediately felt improvements in control and speed with his 6.7 race sail.  I had no problems with the VMax 39 with my 7.0 Stitch but I am a lot heavier than Charl.  The bottom line is that anyone trying this board needs to experiment with smaller fins than they may have had on previous Manta 71's.



Speaking of fins here are two tasty ones:

This is ERD's carbon slalom fin.  Nice design and by all accounts one hot thing

These are Silverline fins from KW Fins.  What makes them different is the fact that they are hollow.  I always take notice when a sailor who has been struggling for a few years starts to win races.  Nicholas Warembourg (that is him below) is such a sailor.  He is one of the people behind these fins so they obviously work.  Look them up! 

Talk to you soon
(Our season is basically over but it looks as if we will get a few days sailing starting Saturday).

The Medium Sized, Fast Board Problem

Hi

I have been doing some re-thinking about my ideal board quiver mix and I thought I would share some of this with you.

My ideal four board quiver has always been Big Slalom, Medium Slalom, Big Freewave, Small Freewave.  I have always seen the medium slalom board as a 70(ish)/110(ish) pure slalom or fast freerace design.  This is the part I have been re-thinking.  Recent sailing sessions have me convinced that for my weight (90kg), I need a wider board for this slot.  I am convinced that I need to be looking for something around 75cm wide and 120l in volume.

To this end, I asked Anthony for a ride on a Tabou Thunder 120/75.  He only has these boards in the heavy construction but I thought I would get a good impression anyway.  I took the board out with my 7m Vandal Stitch and the standard 42cm fin.  The wind was a bit marginal

 

The good news is that under full power, this board can be as fast as all but the fastest racers on pure slalom equipment (I blasted with one of the best).  The thing is an absolute rocket ship when ridden with intensity and it treats rough water with disdain.  A huge surprise.

The bad news is that I battled to get the board planing.  Charl (admittedly much lighter than me) was on a new Manta 116/71 with a 6.5 NCX Pro and was blasting off the beach and out of the gybes at the other end whereas I was left standing.  No good even if I was as fast once going.  The board just seems to want to sink into the water in marginal wind and pumping seems to make things worse.  Very disappointing.  Andy had no such problem with the bigger Thunder and he suggests that I may have had the mast foot too far forward.  I will try moving it back if I can scrounge another ride from Anthony.  If I can solve the planing problem then the Thunder 120 will become my choice for this slot.

Until I come right however, the Starboard Futura 121 keeps its position in my personal dream board quiver.

If you are a lighter sailor then you must consider the 2014 Manta 71/116 for this slot.  An awesome, awesome machine when properly finned!  We have received some guidance from Ben vd Steen about the fins for this board and I will share this info with you in the next post.

Talk to you soon