View Full Version : Mast TIP extensions?

29th April 2010, 07:00 PM
Anyone used tip extensions? How they works?
My SW car doesn't accept masts longer than 460. I've seen on ebay and bought a FS 5000 (90%) 460/30. It was a special and reinforced mast made for the Gaastra with the upper mast extension like Gaastra Total Flow. I want to use it also with mi nocam 9,5 that requires 520 mast, luff 547, I've got a 57 carbon base extension and I'm also thinking at a 30 cm TIP extension (=547). This way I'm gonna preserve more the natural curve of the mast instead of adding another mast base extension and attachin the boom at about 40 cm from the mast base itself...
Consider that this mast was made to bear a tip extension in a fully loaded cambered race sail, instead of me that I want to use it in a nocam sail for the lightest winds. Fiberspar in their instructions booklets of the time used to write : "why not recommended you can use mast tip extensions..."
What do you think about?

P.s.: I live in Venice and park the car in a public parking outside Venice, so stuff must be left inside the car, not over the roof... No answer on another forum to the same question.

Nico from Venice

29th April 2010, 07:38 PM
Hi Nico, won't your mast be too soft for your 9.5 sail anyway? Alternatively you could consider the 3 pieces mast from North Sails in 490 / IMCS 28. I'm not sure bend curve is compatible, though...

29th April 2010, 10:32 PM
The other issue is that even with base and mast tip extensions, you will be at the exact luff length. Will you be able to downhaul the appropriate amount? I guess it depends on how precise the measurements are and the pulley location.

How tall are you? If you extend the mast up 57cm, your boom my be below the reinforced section of the mast and you my crush the mast when clamping on the boom.

A three piece mast sounds like the solution.

At one time, I had a mast locking system which would work with the bottom section of the mast. A gizmo plugged into the base, twisted on tight and had a cable locking system which attached to the roof rack.

1st May 2010, 12:50 AM
Thanks for taking interest in my question.
For the luff leght I think It would work, and let me downhaul correctly. In fact I bought the sail in 2003 right because I had a North Sting 490/28 (30%) and this carbon extension left by the short life of my Neil Pryde Ultralight 7,8.
So with a stiffer mast than 490/28 I think there would be no problem from mast+base extension.
But I don't know how tip extensions work, base extension usually affects a little the bending curve, but tip section is on the most critical section of the mast...
About crushing the mast if you could see this FS you coud agree with me that is one of the strongest mast ever seen, it seems way thicker than other Fiberspar than I got, and in fact the top section doesn't slip without problem inside the base as with all my other FS sdm masts.
Sail is HSM Stealth and new North Masts are not recommended for HSM, different bending curve. And this FS 5000 90% was bought perfect for 86 euro...

4th May 2010, 02:40 PM
Mmmm, Challenger tip (or better said TOP extension) is out of stock and I think they will not produce it anymore.
I've found on Nautix website a similar top mast extension, 30 cm for 22 mm (inside) diameter mast would fit perfectly in the tip of my mast, even if extensions should be used for rdm masts, but tips aren't the same in sdm/rdm? And therefore my special 460/30 seems for thickness a giant fat rdm!
I've sent a info request to Nautix but at the moment no reply.
Someone knows some other brand who still sells mast top extension?

4th May 2010, 07:42 PM
in general, mast tip extensions work very well - better than a too long base extension!
used a severne s-1 5.9 wavesail with a 400 rdm mast and 25cm tip (custom) extension

severne used to have one in the programm

4th May 2010, 09:39 PM
I donŽt know this sail that you own... but I have a severne overdrive 11, and I can use 30cm of tip extension, with very good results for both sail shape and control; I made the tip myself, with and old piece of 75% mast...
Now instead of using a lot of extension at the base, I use only this tip...

4th May 2010, 10:02 PM
I love your freedom of mind. About the sail is an Hot Sails Maui Stealth 9,5 from 2003, not used so may times just because of the carryng problems of a 520 mast in my car. Luff 547
How did you make this extension? I mean, is it external or fits like the Nautix one inside the tip of the mast?
I've searched but not found the Severne top extension, if someone can write here the link for the product will make me happy. BUt the idea of making it by myself without spending money (Challenger had a listprice of 86 euro=113 Usd, the same price I paid for the whole FS mast...)
Internal like the Nautix seems to have better fit, doesn't scratch the external surface of mast tip, and smoother surface for sail sleeve, but I would have to pull away mast cap every time I use the extension. On the opposite the external one seems more user friendly but with worster flex and pheraphs problems in rotating the sail and/or shape. Pheraphs less problems making and external one with an alloy linking tube...
Thanks for your suggestions

5th May 2010, 01:15 AM
The linking tube must be carbon... otherwise could make it too soft; I used a piece of an old carbon boom extension (the back of it)... then just sand it till it fit in one side the mast, and the other side to fit the tip extension (in my case I used a piece of a fiberspar mast, while my original mast was severne blueline, so different diameters); Then everytime I use it, I tape it to make sure it wonŽt slip while rigging;
I am not the only one who uses this sort of tip around here, after the first guy tried, a lot of people have been using home made tip extensions with success; Another tipo is pay attention on the IMCS of the mast that you are using as extension, as it will affect the shape of your sail...
I hope this helps, and goog luck... At Carbonsugar.com Sean Obrien even teach how to build a base extension by yourself...

Unregistered - Nico
5th May 2010, 03:51 AM
And so let's see if I have correctly understood: it is extension with EXTERNAL linking tube, that means totally different system compared to the internal Nautix one tha can be seen here (and pheraphs only in photo...):http://www.nautix.com/Nautix/Nautix.nsf/VuVoileGamme/b26f9225355e6fc3c1256d980030d730!OpenDocument&Langue=En
It seems not impossible to build! I've already made a splitboard snowboard for my girl so should be not a long work. If Nautix keep on ignoring my request I'm gonna make it by myself
What lenght of external linking tube you suggest? Fiberspar old booklets tells: " must allow a 4 inch (10 cm) ovelap inside OR OUTSIDE the top of the mast" Sounds good?
What's the best lenght in your experience?
And in the opposite, is it the Severne extension you talked about still available? Obviously not at an NP or NS style price...
Thanks, Nico, Venice

Unregistered - Nico
5th May 2010, 05:00 PM
Mmmm, meanwhile this morning Nautix answered me, extensions is available in France, it is 100% carbon... List price is not so low in France, but as Italian distributor told me I can have some discount, I think I'm gonna order it

5th May 2010, 08:03 PM
Sorry if my message was confusing. My linkinking tube is internal, as the one on the website that you pointed. About 5cm inside on each side. The linking tube is the one that you sand till gets IN the mast and IN the tip extension. If you are interested let me know so IŽll photograph it 4 u;

Unregistered - Nico
5th May 2010, 09:45 PM
No, sorry, it's me that I haven't paid full attention to the words of your message, not seeing the clear word "a piece of and old carbon BOOM extension" and incorrectly thinking at a piece of MAST, so that could be only EXTERNAL in my mind.
And also this solve the problem about doing it or buyin' it since I've some pieces of mast but no pieces of carbon boom at all, and no windsurfing friends to give me it. So no photo is necessary, in any case all is clear. And therefore I've already ordered the extension (if they confirm me the discounted price...).
Thanks really a lot for help.