Does anyone have any concrete evidence to support the theory that a carbon extension makes a difference to the performance of a sail?
Makes a difference if it snaps totally, rather than bends.
I went off them after a very very big swim and realising ally would have not failed.
Its at the centre of everything so swing weight is not an issue.
I can see it matters on race sails with a lot of extension and super high level competing - maybe.
IMHO
Only the really kool dudes have them.Me I have both but mostly carbon, and one really trick hybrid one from Hot Sails.
so iam on,y moderately kool,but iam a dude.
if you needed one, I would do the carbon.i don't feel any real weight gain is accomplished,especially that low and you dont lift it except to carry it.Its low in that mast and from a flex standpoint ,nill, advantage.
if I worried about something breaking, I probably would never sail.
Have had 2 Chinook carbon extensions both the SDM and the RDM one snapped in half using race sails. Had alu's before and after. Never broke, bent or snapped an alu one. If you have money to spend, a carbon fetish, care about saving about 100 grams and want to enjoy the occasional swim back to shore with your kit? Get a fancy carbon extension which nobody will see 
The only combo I am considering it with is my SLW pro using an 8.7 V8 rigged with 90% mast and carbon boom to maximise early planing.. I'm just a recreational sailor so wouldn't consider one for my smaller rigs.
Worth the money for the above scenario? Would it make a difference?
Select to expand quoteOrange Whip said..
Does anyone have any concrete evidence to support the theory that a carbon extension makes a difference to the performance of a sail?
Yep, 00.01% improvement, and makes your wallet lighter.
i always notice In videos the PWA pro's always seem to use alu extensions, I guess they are more bothered about reliability and fewer breakages than saving a few ounces!!!
I have two Chinook 45 cm std ext . One carbon , ( only because I got it at the cost of an alloy ) , and the other alloy .The max ext I use on any of my sails is 22 cm , so a flex difference is probably not a thing . I weighed both and are almost identical in weight and that's with long extensions . I tend to use the carbon one because it's cooler . I should use the alloy because it's stronger . Also to add to my non logical choice , the carbon one would deteriate in the sun and heat .
Select to expand quotemark62 said..Orange Whip said..
Does anyone have any concrete evidence to support the theory that a carbon extension makes a difference to the performance of a sail?
Yep, 00.01% improvement, and makes your wallet lighter.
i always notice In videos the PWA pro's always seem to use alu extensions, I guess they are more bothered about reliability and fewer breakages than saving a few ounces!!!
Thanks. So using the carbon extension has absolutely no effect on providing the platform the sail was designed to be rigged on and thereby perfecting the shape of the sail to how it was intended when designed? I.E. the addition of the carbon extension will have zero influence on the final shape of the sail when rigged? (In my case rigging 8.7 on a 490 mast needing 32cm of extension)
I would think there is more difference in the sail set by how much extension is up the mast.
Select to expand quoteOrange Whip said..mark62 said..Orange Whip said..
Does anyone have any concrete evidence to support the theory that a carbon extension makes a difference to the performance of a sail?
Yep, 00.01% improvement, and makes your wallet lighter.
i always notice In videos the PWA pro's always seem to use alu extensions, I guess they are more bothered about reliability and fewer breakages than saving a few ounces!!!
Thanks. So using the carbon extension has absolutely no effect on providing the platform the sail was designed to be rigged on and thereby perfecting the shape of the sail to how it was intended when designed? I.E. the addition of the carbon extension will have zero influence on the final shape of the sail when rigged? (In my case rigging 8.7 on a 490 mast needing 32cm of extension)
That's right, it shouldn't have any effect on the final sail shape, that's a job for the mast. I pretty sure most sails are designed using (their own brand) alu extension too.
And I fully agree with imax1 about the amount of extension up the mast. Not to good using a 48cm extension when you only need say 10cm.
Just my 2 cents worth :)
OW, save ya coin & get an 8.2. lol
I have NP Carbon RDM cos its cool and cost effective at $180 but cool factor gets hidden in the mast once rigged so noone can see it on the beach or on the water.
I have short NP carbon ext (used, $50) and its set on 14cm but Im buggered if I can tell the difference between it and alloy extensions??
Been going strong for 8 years now.
I use carbon extensions mostly for the weight saving.
You get a better strength to weight ratio with a pre preg carbon laminate than you do with aluminium.
With RDM extensions, you can argue that it is better for an extension to bend in surf accidents than it is for a carbon one to snap - but I have never had a carbon one snap while I did have a bent aluminium one.
The extension used however should make little change to the setting of your sail.
Where an extension does affect the sail setting is when you insert a long extension or, more commonly, where the pulleys on the extension are set further back from your mast - which then affects the position of the sail tack when down hauling, essentially changing batten rotation for the bottom batten(s).
Alluminium ,Chinook ,for me always, double pin, .
Two seasons and then you get slug out, does this happen with carbon?
Both carbon and ally extensions feel the same in weight.
My $0.02... lots of early carbon-extensions, snapped... They were 100% carbon - most I came across, had pressure-point fatigue the both going through the rod, which is where then snapped. Carbon doesn't like being under point load, and it isn't as good at compression as Alu.
Some of the newer ones have carbon-overwrap-aluminium... if implemented correctly is state of the art for strength vs weight (which is why rockets use it).
Select to expand quoteappleman said..
Alluminium ,Chinook ,for me always, double pin, .
Two seasons and then you get slug out, does this happen with carbon?
Both carbon and ally extensions feel the same in weight.
appleman I'd keep an eye on that fracture.....
Or maybe you camera is just too good and its not that bad...?
Hi Appleman!
When you change your extensions, you should do the same with you UJ, as they wear as well and your new extensions wear faster with an old UJ.
BR, David
Great tip Db2, yes uni joints replace at least every 2 seasons ,budget.
The picture was of an old extension .
I do find every two seasons that most ally extensions receive that amount of wear and tear.
I windsurf on a budget, and also own a carbon extension, the weight difference is bugger all, and my mast will break before the alluminium extension does.
Carbon v ally ?
Ally, for me.
Peace out mo fo's
Select to expand quoteOrange Whip said..
Does anyone have any concrete evidence to support the theory that a carbon extension makes a difference to the performance of a sail?
Why not? they are stronger, and lighter. I have a 45 AL360 Carbon that feels as solid as a rock. The carbon tube reaches all the way to the bottom of the extension. But they also have them in aluminum and ergal .. and wood-look aluminum.
Select to expand quotemathew said..
My $0.02... lots of early carbon-extensions, snapped... They were 100% carbon - most I came across, had pressure-point fatigue the both going through the rod, which is where then snapped. Carbon doesn't like being under point load, and it isn't as good at compression as Alu.
Some of the newer ones have carbon-overwrap-aluminium... if implemented correctly is state of the art for strength vs weight (which is why rockets use it).
How do they stop corrosion of the ally? I've seen a carbon extension split the carbon tube along join where it was over alloy reinforced bit & there was significant corrosion underneath. Don't get why they were using joined tube for the extension also.
I use all carbon extensions in rdm. Went to using carbon as the race sails were bending & breaking the alloy extensions at the time but now there are some alloy extensions that are far stronger than the carbons.
If your rig is taking big enough hits to break the extension personally i'd prefer for it to break rather than mast, sail pulley or mast base as you can always sail home with shorter extension.
Select to expand quotemkseven said..
Don't get why they were using joined tube for the extension also.
Unfortunately that is how Extruded Aluminium Tube is made, unless machined from billet there will always be a seam.
Was referring to a carbon extension, the seam being the inconsitency in the layup thats where it split.
Select to expand quoteAUS 808 said..mkseven said..
Don't get why they were using joined tube for the extension also.
Unfortunately that is how Extruded Aluminium Tube is made, unless machined from billet there will always be a seam.
Sorry to correct you but thats not true.
Extruded has no seam . Its extruded not welded.
Select to expand quotemkseven said..
How do they stop corrosion of the ally?
Epoxy is often used as a barrier to corrosion, ref: www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532005000100015
The galvanic corrosion is mostly a result of the carbon touching the alu. And it is likely to have plain old surface corrosion of the alu (alu does rust, but the AlO layer sticks to the Al metal).
So if your surface prep is good, your barrier layer is good, and you eliminate air at the boundary layer... then carbon-overwrap gives you best strength-to-weight. Similar technique applies to other metals, such as steel. [ ref: rockets and "COPV" ]
