kiwi307 said...landyacht said...Gizmo said...
Here is a link to an Australian manufacturer of carbon fiber tubing and yacht masts..
http://www.cstcomposites.com/index.htm
I had a good look at what was on offer, then sat down and calculated the cost for the materials for a carbon class 5 mast.
i ended with a number( the prices are all 2010) of $937 plus freight to kal
msuch a kids yacht really has no need for carbon, so does anybody know a site for glass/epoxy
I am curious as to why you would spend any time calculating the cost of a mast which would not be legal in the class.[}:)]
For the small yacht (Hummingbird) why not just use a single length of tube? You are going to carry it assembled on a trailer so ???
FWIW before Landyacht got involved with the class 5 we used 50 by 3mm wall tube with a dowel (wood) in the bottom 2 metres and they worked just fine, temper was T6
Idont know how I got the blame for introducing thinner walledhigh tensile sections to landyachting!
transporting long masts has been a problem as long as class 5 yachts have been around. in about 1987 we became aware of lighter section s in a telescoping range that could be used for class5 masts.
previously we were using48.7x4.7wall T6 scaff with a wooden plug. if you wanted a 2 piece mast there was a section around 40mm that would fit, but it would inevitably bend and was incredibly heavy, especially up high.
then came the lovely 2 piece T8 masts on the winger and faze 5 Given yachts courtesy of Ron Given , a new zealand catamaran designer.
back then i could walk into a warehouse on scarborough beach road and buy it by the truckload.
we bought 3 batches over the next 25 years ,in 87,91,2007.
when we bought a batch in 2007 they delivered about 2/3 of what we ordered , and explained that this stuff was the last of the mountain of stock we had been buying from, then told us that when a big enough order for the rest of the sections came in we would get the rest( it was all coming from sydney). when we explained that the missing sections were for the middle of the job and we needed it all not some of it , they milled the rest of the order.
since then none of the sections have been available, and I believe the mill has now closed.
weve run out of suitable ally.
That why Ive been investigating carbon. I believe it is possible to buy off the shelf,windsurfer mast that would suit a class 5.
ok its against the rules, but if you cant make a mast, you need to look into the future and find an alternative.
the mast Ive just finished has to break down to 2m sections to fit in a crate,and Ive had to use a cold drawn steel section to replace one of the now unavailable ally sections. of the 4 sections used in a mast,all 4 are unavailable and Ive used all but 1 length of my personal stock.
sandgropers club had to "import" their replacements from the east. and that supplier has only a few masts left
Alan , in Europe you have the advantage of numbers. It was explained to me by seabreeze member Frogy that all the french manufacturers combined were able to make up a big enough order each year to warrant the mill to make the required material. It would seem like a good idea to all have ally masts rather than going to composite masts, if you consider that if 1 of the group changes the others would have to carry the burden of a bigger order.
i would suggest that the kinds of lengths and strengths needed for a hummingbird kit could be achieved with a section from an antenna manufacturer or mast manufacturer. it would be worth trying to track down those who made the early "wally masts" as the original Blue windsurfer brand masts are exactly the diameter,length and flex needed for this project..
I would suggest taking one of those masts to someone like Windrush in east fremantle and finding out what it would take to "re-invent" them
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