I have been looking to re-arranging my quiver of smaller race/speed sails. Looking at being able to get a mast to fit 6.6 to a 5.8 or 5.0.
I was more interested in how you choose a good 'donor' mast for the extension. Obviously this will depend on the mast you use it on. Im wondering if I was to use it on a mast with a stiffer top section, such as a maui mast, would i have to get a top section with relatively the same stiffness or could I use a softer extension.

Would this then make the exhaust in the sail un-even?

If anyone knows of an article or instruction video on the basics of making a tip extension, that would be most helpful....

Also do Gaastra and Maui masts both have the stiffer top section?

I made one out of a broken 100% carbon mast but I haven't used it yet.

I dont think the type/brand of mast will make any difference as the tip really wont be flexing much if at all.The main thing I kept in mind was thr boom clamp position as you wouldnt want it clamped below the mast reinforcing area.

The mast with the tip extension fitted should be softer due to the same flex spread over a longer area.
Dont know if I am correct or not but that is how I saw the big picture.

Hope my spelling is up to your high standard sausage Feel free to correct me if it isnt

I agree with fullmoon. The type/stiffness will not make any difference as it will be so short (300mm?) If it was to make any difference it would be negated due to the sleeve/join.
If you make one and you know someone with a mast you trying to imitate simply do a bend test on each one.

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steller_3 said...

I have been looking to re-arranging my quiver of smaller race/speed sails. Looking at being able to get a mast to fit 6.6 to a 5.8 or 5.0.
I was more interested in how you choose a good 'donor' mast for the extension. Obviously this will depend on the mast you use it on. Im wondering if I was to use it on a mast with a stiffer top section, such as a maui mast, would i have to get a top section with relatively the same stiffness or could I use a softer extension.

Would this then make the exhaust in the sail un-even?

If anyone knows of an article or instruction video on the basics of making a tip extension, that would be most helpful....

Also do Gaastra and Maui masts both have the stiffer top section?

That's a pretty big range Ric. If your 5 is an NP it will like a mast with a stiff bottom. If your 6.6 is a sail that likes a 12% bend or even a Maui (about 10% I think) the stiffness in the bottom of an NP 400 would be pretty close. I have done that in the past and it worked surprisingly well but I used a long conventional extension, and I was running it in an Ezzy Infinity and they are not too fussy. I think its best to keep tip extensions as short as you can manage.

Something to note is that masts with the same IMCS have the same stiffness regardless of length. However finding masts that differ from standard stiffness for length is near impossible.

Tim Hughes makes some pretty good tip extensions by expanding aluminium tube.

Current Gaastras are 12% bend I think like Lofts etc.unlike Maui. They used to be stiffer in the top in the days when Barry Spannier worked for them and for the year following his leaving.

hmm interesting point Notwal. I was under the assumption that maui masts differed from loft, np, north as they had a slightly stiffer top section.

The other thing is i have never seen one of these 'tip extensions' excuse my asking but does it does fit on the top 'tip' of the mast, correct?

I am looking at running a 5.0m (ish) race sail a 5.8 warp and a 6.6m. The 6.6 and 5.0 are yet to be purchased More just dreaming and looking at possible options. This would make the extension 30cm max, or 25cm and 5+cm aluminium mast extension.

correction, after looking I would be running the 6.6 on a 460 mast. So would only need to extend the 400 mast to 430cm.

Correct me if I'm wrong but I assume that the correct bend mast is already being used so the only change should be the stiffness when you add the extension.

My tip extension was 20cm plus 10 cm mast base extension to give the 30cm mast step.

Hi rich have a look at mine or Pierres tip ext they work really well and just slip over the top section. yes they do make the top section softer which then gives you more twist.
Have to be careful though it doesn't always work so well depending on the sail.
Pretty sure Gaastras are constant curve these days.

I actually have TWO mast tip extenders, which I picked up somewhere, they were made by some euro company...but I've never used them so all I can tell you is, yes, the number is TWO....

...would you like to know the colours?

Wet Willy what a you doing back here son? its been a while since i have seen you old pal .. you remember me its windwarning, tom444

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steller_3 said...

hmm interesting point Notwal. I was under the assumption that maui masts differed from loft, np, north as they had a slightly stiffer top section.

Yes that's right. However the top is for twist and ventilation. If its a bit too loose you don't lose much. In fact for a light sailor it may offer a small improvement in lowering the centre of lift a bit. It's more important to get the bottom, that is the power zone right.

I've hesitated to use my extenders because, well, nobody uses them, do they?

Farkin lame, I know - I should be pushing the envelope! Hell, according to my buddy's wind meter, today we got 65 knots here!! Um...I mean, 6.5 knots...

How would a 20cm tip extender affect a sail's performance, on (a) SDM masts in freeride conditions, and (b) RDM masts in bump & jump conditions?

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flipper4444 said...

Wet Willy what a you doing back here son? its been a while since i have seen you old pal .. you remember me its windwarning, tom444

Son, I been busy, out here there's a whole lotta beer needs drinking, and I am the man to do it....

...I feel like a b@st@rd; I promise to test my mast tip extensins soon and let the whole world know...

Remember to tie a string on it willy,you wouldnt want to lose it up there would you?

Its only 20cm after all.[}:)]

What is the best way to stop the tip extension perminently being stuck on the top of the mast?
I have a couple doner masts to choose from, should I risk trying an x5 NP or stick with a 50% north?

Hi All,

Sorry to be slightly off topic, but there seems to be some people here who know alot about masts and may be able to tell me about a setup I am planning to try.

I currently have a 2008 NP Hellcat 6.2 and recommended X3 430 mast. I am getting a 2010 NP Hellcat 7.2. I have opted to save the cash and not buy a mast suit the new sail. Luff on new sail is 461, and recommended mast is NP 460. I have just purchased a 48cm extendion that I will run at about 32cm. So my hope is that the 7.2 will work well on the 430 mast with around 32cm of extension.

Can anyone comment on how well it is likely to work and what I should be looking for to determine this. Obviously I want the new sail to perform to potential for as little $$$ as possible, but I may not be a great judge of whether it is actually working properly as I have never owned a sail this large, and I have mainly got it to put on starboard GO in light air when there is not enough for my FSW 92 and the 6.2 (which needs about 15 knots). Hoping to get sailing in 8-12 knots. If I can determine that it could work better I would be looking to improve it.

Another thing... I have another mast I have had for some time that I use with my 5.0. It is a 430 Fibrespare Reflex Wave. I believe it would be stiffer in the top than the NP X3 430. Not sure if this may be a better option in the NP 7.2... as in it would probably be a stiffer mast, and would therefor hold more stiffness when extended... but not sure what happens to the curve shape.

Thanks,

Adrian

Hey Rich.
Am not sure how the other guys are doing it but if you were to cut a section of your donor tube so that it neatly slides over the tip of your mast you could glue another bit of the donor mast tube up inside the new extention at the correct height so that the load bears on that inner sleeve. It wouldn't have to be too long as long as you use a good epoxy adhesive or a methacrylate such as plexus. make sure you sand the areas to be glued well

Stellar - Carbon Sugar (FW pro) has a awesome article on making bottom extenders carbonsugar.com/construction/the-10-step-carbon-extender/