i550class.org

I have to say that the i550 is probably the most comfortable boat I've been on for a nice afternoon sail with family or friends.

That bright cabin top looks very nice!

And construction looks robust! Hope mine doesn't fall apart now....

Busted the boat out of the garage, cleaned it up, and watched it sit in my driveway as two solid days of thunderstorms rolled through. Drat!

Hopefully the third day will bring fair winds and a bit of sunshine. Time to sail, at least here where the season is short.

Ryderp,

What mast are you using?. How many pounds per foot?
Thanks

I'm using a Dwyer DM4. It weighs 1.05 lbs per foot.

I saw your note on SA about the weight of the mast being a concern. I've had my boat over on its ear a couple of times (my spin is way too big), and the boat popped right up as soon as I let off the lines.

Phil

Here is a view of the mast - looking up:

.
...wow,,that chute's chord looks rather wiiiiiiide!

I've been debating whether to get another smaller chute or to have this one cut down.

Phil

Listening in on the impute from others on here, I think I will do more research, do we have any good sailmakers who have actually sailed an i550?,,, when the Boston/Doyles joined the U20 group and started doing R&D for them, they made substantial improvement's to how the boat sails, it would be awesome to get someone on board to help us optimize our i550's.

Mark

ryderp wrote:I'm using a Dwyer DM4. It weighs 1.05 lbs per foot.

I saw your note on SA about the weight of the mast being a concern. I've had my boat over on its ear a couple of times (my spin is way too big), and the boat popped right up as soon as I let off the lines.

Phil

Here is a view of the mast - looking up:

IMG_1191.jpg

What kind of wind are you sailing in normally. I had posted my question about weight while considering using a freebie U20 mast, but then decided it was too heavy, Ballengers weigh in at 1.5 pounds per foot, which I decided was just too much extra weight aloft, I have since found a viper mast in AZ that will be delivered to the Dillon open. Do you have the drawing to your Dwyer setup?.

Thanks for all your help,
Mark

Sorry, I don't have any drawings. I have descriptions on my old blog at i550-381.blogspot.com

We normally sail in light to moderate air (<20kts). I bought my sails second hand but unused (and still at the sail loft) from an i550 builder who got frustrated and gave up on his build, so I didn't determine the dimensions of the sails.

Phil

i550sailor@aol.com wrote:Listening in on the impute from others on here, I think I will do more research, do we have any good sailmakers who have actually sailed an i550?,,, when the Boston/Doyles joined the U20 group and started doing R&D for them, they made substantial improvement's to how the boat sails, it would be awesome to get someone on board to help us optimize our i550's. Mark

....unfortunately,,a sailmaker's input won't help so much with details since 550's have a wider variety of spars.

...my bet on the right chute would be bigger isn't necessarily better

Micah,

I hear you on the spars, the U20's now have C-tech and Forte in Carbon and Ballenger and ???? one other for AL,,,, and the sail cuts are different,,, how much I don't know. I got the boat flipped and the bottom started,,, and thought I had better start figuring out my sails.

i550sailor@aol.com wrote:Micah,

I hear you on the spars, the U20's now have C-tech and Forte in Carbon and Ballenger and ???? one other for AL,,,, and the sail cuts are different,,, how much I don't know. I got the boat flipped and the bottom started,,, and thought I had better start figuring out my sails.

.....sailmaker's will hate me**,,,but a used set of Melges 20 sails will get you started nicely!

...with the Viper mast,,,see if you can pull the sleeve out the base--not easy but worthwhile...haven't done it on a viper spar yet,,but done on a finn mast


....**..except for the modification$ they make

I will be using a Viper mast and Melges 20 sails and wonder if removing the sleeve will weaken the mast. My mast will not be stepped on the deck but run through and stepped on the reinforced cabin sole. That is if I ever get the boat done. Last of the cloth going on this weekend.
Noel

noemar wrote:I will be using a Viper mast and Melges 20 sails and wonder if removing the sleeve will weaken the mast. My mast will not be stepped on the deck but run through and stepped on the reinforced cabin sole. That is if I ever get the boat done. Last of the cloth going on this weekend.
Noel

...those masts are said to be quite heavily built,,,,,'tswat I'd do

If you are rigging with double spreaders, then you shouldn't need a tree trunk mast. The dm4 is not a heavy duty spar at all. I bet the viper mast without the sleeve is bigger and stiffer than the dm4. If you are using a traveler, then you shouldn't be stressing out the bottom of the spar with vang pressure most of the time, another reason to loose the sleeve if you can.

.

...just rec'd a Viper Spar....45pounds over a 30length,,,but the sleeving is a full half of the sparlength,,and equal wall thickness,,,so the spar itself is ~1lb/foot....sounds similar to the Dwyer spar-weight....there's a lot of rivets holding the sleeve in place-it'd be important to overdrill all of these before attempting to remove the sleeve,,,then use a cutter to cut-through some of the mast-base,,,exposing the sleeve inside.....then attach to a cum-along and with some luck--voila-presto!!!

...I'll let yer know how it goes when I get a round twit

The Selden/Proctor 3525 section is lighter than the Dwyer DM-4, but it is longer and wider making it much stiffer. From what I've found from a early Viper owner the sleeve helped an issue of the mast inverting. It also made for high loads needed for prebend. The 12 -13 feet of inner sleeve was the same mast section with the sail track cut off. I'm planning to leave the sleeve in for now and then evaluate removing it later. Attached is a spreadseet with number of Al and CF sections. Link under the section names will take you to the webpages.

As an actual owner of a Dwyer DM4, I can state categorically that it's not exactly a wet noodle. The sailmaker was pretty surprised at it's stiffness when I did a flex test and he plugged the numbers into his computer. Any of the spars that are being discussed will work, and I don't believe that any of them will fail in normal use unless one of the shrouds or spreaders fail - then I think that just about all of them are subject to failure.