Comments on: Why do masts keep breaking?!

By: TG

TG — Mon, 11 Jan 2010 19:57:04 +0000

I can agree with Andreas that the Sailworks Lightstick is stronger than other masts. I’ve been using a 550 for years, on another companies sails, and it’s been rock solid, meanwhile I’ve broken many other masts. It definitely is thicker and stronger, IMO. Unfortunately, the shape isn’t the best for the sails I’m using, but since I’m not racing anymore who cares.

By: The 10-Step Carbon Extender | CarbonSugar.com - The Secrets of High Performance Windsurfing

Fri, 16 Oct 2009 02:41:46 +0000

[...] you’ve been sailing FW for a few seasons then no doubt you’ve broken a mast at some point or know someone who has. Ever wondered what you could do with the broken pieces? With [...]

By: Sean OBrien

Sean OBrien — Sun, 11 Oct 2009 02:31:04 +0000

Hi Pete,

I’m in the process of writing a ‘how to build an extendor’ article right now; should hopefully have it online by the end of this week!

By: .g.e.o.

.g.e.o. — Mon, 05 Oct 2009 07:51:12 +0000

Hi all,
just found this now, it’s very interesting. I have something to share.
I use Maui Sails and have been rigging on the same SRS100 460/25 from 2006 during the last 3 seasons; it’s a very light mast, about 1.6 kg. This season I decided to get another identical one as a backup; so I got a new one, much heavier (1.9 kg). The manufacture told me they did so to make it sturdier. I rigged it an half dozen times, then one day BANG it crashed while I was going out at the beginning of a session, luckily just about 1/4 hour swim from shore.

I looked at the broken mast and asked to the manufacturer how the layup was made and how was reinforced. They told me the layup is, inside to outside: spiral tape; longitudinal fibers; 90° fibers reinforcement; spiral tape. So it seems to me that the added reinforcements, those that brought the weight up from 1.6 to 1.9, have been put on the outside of the 0° fibers.

Now. If one reasons about how stresses go in a mast (concentrated on the backward side of the mast where there are combined effects of flex + downhaul compression) it’s easy to understand that the mast will easier break on the side looking towards the sail body; and that it will break because of compression; and that 0° fibers will tend to go back to their ‘un-stressed’ shape , which is ‘un-bent’: straight. Think about the geometry of the system, this will cause fibers to implode towards the inside of the mast.
This seems to be confirmed by what one sees looking at a broken mast: you usually see broken 0° fibers bent towards the inside of the mast. Look at the pics at the top of this page. I see exactly what I’ve found on my mast: little if any reinforcement inside, broken 0° fibers bent towards the inside, thick 90° reinforcement outside… right where it is 100% useless, as it should rather be INSIDE of the 0° fibers to prevent them from bending inside and implode destroying the mast!
Now I am sure that use of better quality materials, carbon cloth in first, is the really good if expensive solution; but personally I’d feel much safer by knowing that 90° reinforcements are layed up inside of the 0° fibers in my mast. Maybe I am wrong?

By: PH

PH — Sat, 14 Mar 2009 20:38:59 +0000

Hi Sean

How do you build an extender from pieces of broken mast?

Having a few lying around in my shed I would love to put them to a good use.

Congrats on this excellent website!!

Pete

By: JW

JW — Fri, 04 Apr 2008 06:12:09 +0000

Not Sean here but anyway:

Why not use the recommended mast firts? Is is not all in the IMCS allone. North need more topfelx masts and it may be that you have a similar imcs mast but one with less topflex or with a stiffer bottom…. Overall it is the same imcs as reccomended but the curvature is probably not the same as in the recommended mast, my guess.
So my idea would be first to try the recommended mast before doiing something that is out of the box.

Good luck and let us know here what you find out.

By: soffio63

soffio63 — Tue, 01 Apr 2008 21:40:57 +0000

Hi Sean,

Even if I know you don’t use North windsurfing sails, I contact you about a Warp issue for a simple advice.

I’ve purchased a second hand 2006 North 9.0 slalom WARP and I have rigged it with a compatible 520 / IMCS 32 mast.

I’ve noticed this sails is very physical and from recent races I came out really exhausted !

I regularly use North formula and free-race sails with their recommended masts and I valued NS sails for their soft feeling but I feel this sail (9.0) is really hard to drive & control when wind rises.

I wonder if this depends on using a compatible (maybe stiffer) mast than original 520 North (anyway, always IMCS 32).

What do you think if instead of using recommended 520 / IMCS 32 mast I will use a softer 490 mast (or a mix of 520 bottom and 490 top) ??

Thank you in advance for any help.

Regards.

By: Sean OBrien

Sean OBrien — Thu, 27 Mar 2008 02:23:39 +0000

@ Land – I agree. I also cycle, and recently bought a Trek Madone full carbon bike (figured if its good enough for Lance Armstrong, its probably good enough for me!).

The workmanship that goes into a carbon bike frame (even the work that goes into carbon drink bottle holders) is quite astonishing.

But I guess you can have that level of quality when you expect to sell 500,000 units of drink holders instead of maybe 1000-2000 masts. Bike “parts” are cheap, but framesets are still not (retail around US$4500 for my bike), so I guess all products still have to pay for the R&D that goes into their products and their teamrider’s salaries.

I still get a lot of emails from sailors here in Australia, asking what brand of sails they should try this year and whether or not the masts will break. What can you tell them? Every brand is in the same situation (almost)… I have trouble selling second hand sails because I don’t want to sell the masts with them; you need to have so many spare masts to do the tour these days :(

By: Land

Land — Thu, 27 Mar 2008 00:57:17 +0000

Sean congrats for your article.
I would like to share my personal experience and feelings about this matter.
I run windsurf races for almost 30 years now, the same time I also compete in road bicycle and triathlon events and what impresses me the most through all this years is the complete opposite direction that carbon took in those different sports.
While in windsurf we are experiencing breaks, cracks above it all “lack of confidence” in our carbon stuffs ( not forgetting the booms breaks too !!!) the carbon bicycle market had grown significantly throughout this years. Carbon bikes is light, reliable and thanks to mass production is becoming sheaper and sheaper every year.
In my opinion, the problem lays in the eyes of the windsurf executives. While bike market have professionilized generating millions in sales, sponsorship and media worldwide, windsurf, in general, but specially FW is still an amateur sport.

By: Sean OBrien

Sean OBrien — Fri, 14 Mar 2008 04:21:49 +0000

@ John_O – all good points, but you left out…

…”how the heck would I fit this pre-bent mast into my car” ??