I would like to make my own A rig mast for a IOM flush deck, keel stepped mast. I have found some aluminum locally the first is an aircraft aluminum 1/2inch OD with 0.35mm wall thickness 6061 grade $4.15 per ft, and the other is a 1/2 inch OD 1/16 inch wall 6061 grade $1 per foot. So which one would be better, and would the cheaper one be work for someone just sailing for fun.
The rigs I’m building at the moment have 7/16(11.1mm) masts, so it’s not a direct comparison, but… The wall thickness on my masts is 0.5mm, so I’m guessing 0.35mm on a 1/2(12.7mm) mast would be close, if a little skinny, you may need to pre-bend them a touch. 1/16 is over 1.5mm, a good 1mm more than you need, too thick & heavy for my tastes.
Having said that, if you’re going to have to pre-bend the masts, you might as well go for 7/16 O/D.
What?s the ?temper? of the aluminum? If it?s just pure alloy, I wouldn?t use it, because it?s going to be really soft. What you want for an IOM mast is ?6061 T-6? or ?7075 T-9?
The 6061 is a t6. I have also found some 1/2 tent poles at a fancy out doors store, it seams like these might be a good grade of aluminum but they are only 2’ lengths with very snug fitting sleeves(aluminum as well) has any one tried tent poles. Now you are probably going to say why not just buy from a shop that supplies IOM masts, but that would not be fun as I am doing this to tinker if that was the case I would have bought a complete boat from someone else.
Nothing wrong, with wanting to find a local source, you would be amazed that once you find a good local source, how much some of the hobby retailers are marking up the price.
If you are ok with a segmented mast, by all means give it a shot. Segmented masts have some short falls, mainly bending characteristics, and weight, but if your just tinkering, and don?t need to be on the cutting edge, you should be good to go.
Thank for the responces Dan, would you glue the section together and if so with CA glue or somthing else?
I think CA will work fine, as long as you don?t want to take the mast apart again.
CA isn’t waterproof. (The stuff originates from field dressings in the Korean war, and is designed to wash off skin eventually…) If the strength of the mast will rely upon the glue, then I guess you’d need something more secure.