blake52 said..
last I checked, 6061-t6 tubes are still available in the US, unfortunately not in the metric sizes that slide nicely into each other. the French are using 7075 in both masts and axles. They referred to our 6061 scaffold tubing as "truck axles" with distain that than can only really be done in French.
Blake, The 6.7 US Mini Guys are using Fed 5 masts. They bought all of them up from S and R marine. Since then they have found a manufacturer that will build them for about $600.00. They are all made from t6 pipe not tube. Pipe i$ cheaper than tube. Part of the process to make the pipe sleeve properly is to have the 1 1/2" pipe milled to fit inside the 1 3/4" pipe. That milling process jacks the price up. I found a way around the milling process by mixing metric tube with the pipe. I can get all materials for around $225.00 plus shipping online or at my local steel distributor. I have yet to try out the mast.The Alu mast is stiffer than the stiffest Carbon mast. It has less over bend wrinkles in the sail. I am planning a trip to Tule Valley Hardpan or maybe the Gale in mid June to test . See details here -
www.seabreeze.com.au/forums/Land-Yacht-Sailing/General/Mast?page=1With the Mini Skeeter we feel the carbon masts are different even though they have the same ICM numbers. The Naish are noticeable stiffer when comparing pictures or sailing behind one which I have experienced too much of. We think they loose there strength with use and UV's. The 80 % carbon is only being made by one manufacturer. The few exiting 520 masts being made are 100% carbon. About $900.00 and fragile. I think the carbon masts are better suited for smaller boats like the INT 5.6 minis. They have way less loads on them because the righting Moment is so much less. They also have less to travel in a capsize and the contact angle is flatter when the mast smacks the hard. I would never buy a cheapo yard sale mast. The two masts that broke on the Mini Skeeters were those type not Sailworks Masts.