i550class.org

I was able to find a mast, boom and sails from an Aussie 18 for next to nothing. I figure if I can't make them work, I didn't lose much.
Also I know I can't fool anybody, so I am sure from my terminology that you will realize that I am not a sailor. I can build things though...

The mast is 28' and has two shrouds in the shape of a diamond to keep it stiff, as I understand the Aussie 18 has no forestay. It is 3" in diameter at the base (3/16" thick aluminum) and tapers to 1-1/2" at the top. The boom is 11' long, which would put it hanging over my transom about 6". I was thinking about cutting the mast down to approximately 26' at the base; cutting 2' off of the boom and maybe having the main sail altered to fit the new specifications. (Also it should be noted that I'm not too concerned about the rules since I will never be racing anybody down here in Texas - just mainly concerned about stability, self-righting and safety) So here are my questions:

1) Is there any reason why I should not use this mast for the i550?

2) Should I remove the diamond shrouds? Will they be in the way if I need to leave them?

3) Should I not cut anything down to size and leave the main sail alone as well, or will this be too much for this boat?
Also cutting the mast down 2' will only leave about 16"' of clearance from the cabin top to the boom if I leave the main the length that it currently is, so head clearance might suffer a bit.

Any and all thoughts are appreciated. Pic attached.

Hmmm...probably be best if someone from OZ chimes in, but I'll take a shot.

I'm wondering what vintage this rig is from, in terms of an 18. It's obviously from a "modern" 18, as I think the classics used a sliding gunter rig. But it's metal and pretty short at 28' -- the newer 18s are more like 30 to 33 feet and I think 33 is the tallest. But this looks like the rig from an older iteration of the skiff.

The 18s have pretty narrow beam, like six feet or so, and that's why the spreaders are so short. For the beamier i550, you'll need to affix longer spreaders which isn't a colossal hassle, but something to think about.

Cutting some bit off the mast may lower the boom to a point where it's a hazard or a discomfort to tacking and jibing, so be weary of that. You don't want the boom to be so low you have to lay on the cockpit sole to tack.

WIth regard to the main, the photo doesn't look like the main goes to full hoist, is that another 2-3 feet of mast height close to the garage? So maybe the main will fit on 23' of P (main luff) - hard to tell. It looks like there may be a set of jumpers above the spreaders...is that what we are seeing there? Those can be detached and left off, unless the rig is so limber they'd be needed (maybe so as you won't have a backstay).

I think the boats had a wire luff headsail...you'll have to run a forestay no doubt about that. Also the new spreaders should not only be longer but possibly be swept back a bit more (hard to tell from the photo). That headsail looks like the J (foot length) is going to be too long unless you are planning on it being an overlapping headsail (probably not a great idea) so it'll need to be cut down a bit I am guessing. Again, hard to tell with just the photos.

Bottom line is: this is definitely useable on the boat if you don't mind doing some surgery on the rig and sails. Sounds like a huge cost savings and an interesting experiment. Maybe go the Sailing ANarchy Sportboat forum, the i550 thread, and ask some of the Aus/Taz folks what they think. I am just talking out of my rear end and have no feel for the 18s or how folks have adapted skiff rigs to their i550s down there on the other side of the planet!

In the "general chatter" there is a drawing showing the dimensions of the varies masts used. Maybe comparing yours to those can help you decide if it would work. Hope that can help abit.