hey hey

Question:
why cant manufacturers make stronger masts???

In the last two years I have snapped two different brands of skinny masts. One was arguably deserved (bad bad wipeout), the latter was very soft and BS!!!

What i dont understand is why someone cant engineer a stronger mast. As i understand it, nearly all breakages (at least wavesailing ones) occur between the boom and the ferrule (ie. in the top half of the bottom section.). Each time this occurs it is f*uckn expensive, and results in a somewhat dangerous swim!

So why not beef this area up???
I would be more than happy to tolerate 300grams more weight for a mast that was significantly less likely to break. And because the weight would be added in the lower half of the mast, the swing weight added would not be as serious concern.
If this reduces sail performance by 20% so be it- its wavesailing not formula racing. I would like the option to increase durability over performance.

I suppose the problem is strengthing one section loads up another. But surely the wise out there can remedy this problem (c'mon engineers)...

Can someone please help me out?


otherwise, it hurts me to say i may have to take up kiting as my primary sport- I could end up wearing boardies on the outside of my wetty.
This would be TERRIBLE !

quote:

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i may have to take up kiting as my primary sport

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There lies your problem

If you want durable masts use standard diameter glass masts as they are not brittle and will take a flogging. I have a mast that fell out the back of a ute at 100 km/h half way to Lancelin, bounced end over end and is still going stong. Not a scratch or crack to be seen. I think a skinny would have been in a million pieces on the road.

If you want the performance of a 100% carbon skinny then you are going to pay in more ways than just dollars. The main issue with strengthing one area of a mast is that the strengthened area is stiffer and therefore you don't get a constant bend radius to the mast.

Geez leper hope that by breaking a coupla masts it forces you over to the dark side for good
What brands have you been using???

mark / rooster:

the first was a fibrespar radius- as mentioned this one was perhaps deserved. A gnaraloo bomb...

the second was a powerex RDM. This was BS. The mast was about 15months old and sailed very little (less than one summer use) but none the less out of warranty.

Mark- your from esperance yes??? I can imagine that skinny gets a good workout.
That said me and the boys do have a theory that the old ezzy masts (the powerex ones, not the new No Limitz) are particularly strong. For some unknown reason we believe stronger than their powerex counterparts.
This is based on my mates old ezzy RDM which simply refuses to break, much to our fustration:
http://www.outdoorshots.com.au/browse.php?theme=12
- red ezzy, bottom right. One of many...

i've watched a mate snap 2 Ezzy skinies and a powerex skinny.
At the end of the day they will all break.

The problem with carbon is that it is very stiff and doesnt like high impact forces, unlike kevlar.

the best thing would be to increase glass content in skinnies. this may not work aswell as i think it would and would also increase weight dreamtically.

the fundamental problem with a skinny is that the second moment of area is heaps smaller on a skinny than a SDM. this means thet even by increasing the wall thickness of a skinny it will still be more likely to break than a sdm in a bending mode of failure.
you could mess with tapers and layups but then the sails will have to be made specificaly for these funky weird masts. but this wont go down with the market. hence it wont happen.

maybe i'll get a job in the industry and make simo-spec masts for ur mast high gnarloo bombs.
Alternatively you could buy a mast then i could reinforce it with some prepreg carbon or glass i can get. then bake it in the oven at windrush and see what we come up with. but it might **** the mast up?? maybe. testing will be required.

I lurve the sound of kite bladders exploding when the whole thing slams into the water... and then deflates instaneously along with the kiters over pumped ego.

IN regards to the mast issues, I broke 4 sdm masts last season.
2 were a result of big wipeouts in a nasty dredging shore dump (my own fault) 1 replacement snapped mid way through a pushie and the 2nd replacement snapped as i was pumping onto the plane.
It came down to a matter of bad luck + bad batch of masts.
I took the 2 replacement masts back to the supplier/shop and they were replaced under warranty no problems.
It's pretty easy to tell if a mast has failed due to manufacturer defect or rider stupidity by looking at the cracks/splits on the broken pieces

I have also tried skinnnies but have found (and read) that they do not respond well to heavy/bigger sailors as the flex response is dramatically effected by the weight hanging off it.
Iam now using a 100% carbon rdm wave mast (not skinny but not standard fat) which is still going strong and has seen some serious washing machine action.
Logo to mast high waves and still solid as a rock.
Yes, a lot of money to buy, but having seen first hand what it can withstand, and after feeling the difference in response that a 100 carbon mast has over a blend I will not be going back to less carbon content mast.

Horses for courses as they say, but for me the benefits of skinny mast/s is undermined by the cost and the responsiveness/ feel on the water.

Comrade Leper, could be that you need to try something in between (rdm but not full on skinny) if you are spending heaps on replacement masts

Just my 2 cents

although most wavesails dont put that much rigged pressure on masts I tend to cool my masts in the water if they are hot, just something i've done after watching race sails explode at races. My thinking is there is uneven expansion of materials in the mast, whether this is true or not- or even occurs at 60C it has worked for me... I havent broken a mast in 11 years (touch wood).

there's carbon in mast, board, boom oh my god so everything could explode then??
Should I keep everything in the freezer?

Hey mkseven, don't get me wrong I've got no clew about race masts.
I just pictured explosions on the beach after DaVecta question .
I usually break mast on the water and you're gone laugh because most of the time it is because those 2 f*ckin parts are apparently not completly stuck into one another. (well that's what the shop owner tell me), now I 've got masts in gold, and so far so good

I've had a mast break whilst I was getting my wetsuit on and have had one break in the surf.

As with any material be it plastic or metal the application of heeat weakens the molecular strength of the item in fact a lot of plastics retain only about 10% of their compressive yeild strenths at around 80ºC (if not lower).

The forces involved in the down haul of a sail are quite considerable, hence the reason why a lot of racers have to use a winch to down haul a sail, now although a wave sail requires considerably less force it is still generally going through 4 possibly 6 pullies reducing the effort you apply physically, but you still have to put your back into it to tighten it down.

Aerotech are now designing race sails which use less down haul so as to alleviate the problem of the regular mast failure. they do it by building in more shape and having more battens (weight compromise. Our local Avalon sails has been doing it for a while (cleva fella he is)

It should also be noted tht when downhauling a sail you are not only bending it you are also compressing it.

The other forces which we often underestimate is the force of a wave. 1 cubic neter of water weighs 1 tonne, it's moving so it's got energy so the effect is greater.

What you can't quantify is how it impacts on your gear, you could have a mast high screamer clean you up you get your breath back swim to your gear and look in stunned disbelief that it is still intact. The next week you get a wave 1/4 the size and do an "elmo" at the end of it and fall off you resurface and find you've suddenly got a customized mast and a long swim back.

Theres been a lot said about skinny masts being "bullet proof" but in my windsurfing life of a whole 5 years I've seen 3 skinnies end up in the rectangular filing cabinet, on the other hand I have seen 3 std masts go the same way, which are interesting stats when you think of the ratios of skinnies to std out there.

Myself, I stick to low carbon content for waves, they may be heavier and less springy than the higher contects but they seem quite a bit more robust (note I didn't say indestructable)

As a general rule of thumb
Lightness increases cost and is generally weaker.
Make things stronger and they weigh more but also increase the forces elsewhere, a stronger mast requires more downhaul force placing more stress on the sail materials leading to earlier failures there.
Everthing we do is a compromise somehow and until the is a technological leap in either materials or design the we will still be doing this ballancing act.

We all go out in a sport where we should know and expect that we can and will (Hopefully rarely) have breakages, it's the nature of the beast.

Thats my 2 bobs worth anyway. Please correct me if my observations are wildly inaccurate.

Leper, I hope your run of bad luck is at an end and that your waves all line up for you.

Alby


Just remember, the only things indestructable are just things I haven't used yet

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Originally posted by FilthyAmatuer

Lol... Its counter productive for manufacturers to build tougher masts.

Tougher mast = less breakages

less breakages = less new masts sold

less new masts sold = less money

So for the manufacturers tougher masts = less money.

Bad news for us

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Theres allways that.

But in reality it's unlikely. It's very hard to make a product with a limited life without having premature failures and thus damaging your reputation.

The world carbon shortage may end up with manufacturers reintroducing more Aramid fibre (Kevlar) to masts to make them. This will most likely though make masts stiffer (less springy)

How'd ya be anyway Filthy man, haven't seen you for a while. Life being good I hope?

Alby

quote:

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Originally posted by nebbian


So why not make masts that have some of the bend built in?
Obviously you couldn't build all the bend in otherwise it wouldn't stretch the sail nice and tight, but perhaps just a bit of bend would mean you could make it just that little bit stronger...

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Cost would be the issue, it would be extremly difficult to build a pre bent mast with the flex characteristics needed for a sail. Whereas the bent shafts on a boom are ok as they have to remain rigid.

It still all comes back to a compromise sailmakers build their consistant shape into their foils genrally by loading up the masts, without the tension the sails wouldn't handle as well or go as fast.

By reducing the sail tension you have to make the sail profile and shape more rigid which can be done through more battens or reinforcing at the sacrifice of weight.

Going back to the orginal topicin the last year my list of damages were:

2x Alli booms destroyed (one 2 months old) would have been 3 but demoing a carbon boom convinced me to go carbon.

2x Masts (replaced under warentee)

4x Sails with panels torn, admittedly I use s/h sails so some were getting on a bit, but I did manage to shredd an "unrippable" wave sail with my elblow.

1x mast base, bent and stretched all the bolts in 1 high speed prang.

+ way to many dings to boards (on my second tube of kneadit)

My most recent effort was a mast chop on a board which I just bought whilst on my second run (you don't half recon I was annoyed with myself over that)


After each breakage I feel totaly despondant that I can't keep affording to do this.

Then Hardy drags me out for another sail and then I remember why I live with the damage bills.

Alby

quote:

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Originally posted by elmo

Aerotech are now designing race sails which use less down haul so as to alleviate the problem of the regular mast failure. they do it by building in more shape and having more battens (weight compromise. Our local Avalon sails has been doing it for a while (cleva fella he is)

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Ooops in my not breaking any masts choosing sails that dont have extreme luff curves helps (i'm currently using those aerotech's). Straight luff curves is nothing new though, Tushingham went to straighter luffs circa 95/6 after research done by fibrespar suggested that response rates improved by not bending the mast so much. Overall tension and tension under load is harder to achieve, yet the aerotech's (and the tush's from that time) are still very stable.

I did break one mast, it had a premature death when it met a 4wd after dragging me 10m during an insane westerly gust at wello (another reason why i will never go kiting). It was the first time i tried my first brand new race sail and it destroyed the luff sleeve... alot of "would you like fries with that?" went into that sail. Why does it always happen that way, first time you rig a sail or try a board you will break something

good point racycoot.
I have also broken one with duck tape sticking both part together. Seems that the air caught in the top part push both parts apart of few millimeters (when you feed the mast into the sail), so only way is to always check there's no gap before putting downhaul tension.
These masts where the bottom of the range NPryde masts and I reckons they are **house.

I broke few masts in the waves but bizarrely it is not in the biggest wipe-out , or washing machine conditions that it happened.

I agree with leper111 !
make than 50cm area stronger!!

at least we wouldn't end up with dozen of useless top halfs in the shed!