It's been a long while since the last post. This fall we had the opportunity to get three i550s on the water here in Madison on Lake Mendota. We had very light conditions, but managed to get four races in over a short weekend.
Ron Bowman of Lunatic Fringe took home the coveted "Epoxy Cup" with three bullets.
We successfully launched Alchemy for the first time on two weeks ago. We got the sails up and cruised around for twenty minutes or so before the rudder cassette failed. It turned our that the combination of foam covered with carbon that I used for the gudgeons was not sufficiently strong even in moderate breeze.
So the maiden voyage was not completely successful. I ended up carving out the foam and replacing it with oak. This may have been overkill but I know that the rudder cassete will be bulletproof.
I ultimately covered the oak with a layer of carbon uni running parallel to the to the oak and two layers running at +45deg and -45 deg to the oak. We relaunched this Saturday. Traci sat this one out and instructed my dad and I to "go try to break the boat". I love the encouragement!
The beeze was about 6-9kts. We had a really nice sail. The boat was surpisingly fast up wind in that breeze with just the two of us on board. It felt like we nearly got the boat to plane upwind at one point. Nearly, but not quite. Down wind was equally pleasurable, after we got a few rigging issues sorted out. First the cams for the pole deploy and tackline did not want to stay closed. i will need to change the lead on these slightly. Then the spin sheets turned out to be a bit too short. That allowed us to do exactly one jibe---which was hilarious. on the following long jibe, we had a good chance to try to get a feel for the boat. Things felt pretty good downwind. There was a bit of a tendancy to round up in the puffs, but that was more about my feel on tiller. As we progressed on that board, my ability to anticipate the puffs and steer down increased. The speed gains seemed to be good, although we did not have a reliable GPS (MotionX on an iPhone does not do the trick).
So we have a few things to iron out this week and we will be back at on the water again soon!
The i550 now has a rating in Lake Michigan PHRF! The magic number is 120. Yes, it seems rather low. My guess is that the committee in their infinite wisdom decided to rate the boat fast since they weren't sure WTF they were dealing with. Hey, at least they took the step to rate the boat. Good on them for that. We will see how she goes with the club racing here in Madison. PHRF ratings for new designs are naturally in flux.
I expect the certificate by mail tomorrow and will post it here for everyone's reference.
In other news, Traci and I are finally getting settled into our new house so actual work has resumed on the boat. I've got the rudder cassette re-fitted, the hiking straps mounted, and the keel wet sanded and ready to go on the boat. we will likely try to get the boat hoisted next weekend to mount the keel.
Kevin McDaniel (builder of Pipedream) and I were asked to display our boats at an event at Crowley's Yachtyard in Chicago in conjuction with epoxy manufacturer West System, who is also building an i550. We had lots of folks show interest in the boat, and several were already familiar with the boat an came to the show to see them. Pertty cool!
All in all, it was a really great day for the i550! Hopefully we will get a few more builders in the Midwest.
Well, it was 70 degrees today in Madison. A little indian summer is nice!
I picked up the main and jib this week from Ryan at MadSails, and they look pretty darn good! The luff on the jib is a tad long, so we'll have to work on that, but all in all, I think they look fantastic! See for yourself:
I'm putting a few finishing touches on the boom tonight and then a few coats of paint on the keel and rudder and I will be all set to put her to bed for the winter. :(
Ah, we'll see what the weather gods say over the next few weeks...
Lots of activity in the boatworks since the last post:
I put roughly million layers of fairing filler on the keel, and it's finally ready for primer. I also glassed up the sleeve for the rudder cassette. The same as with the keel I used the faired rudder with a layer of 1/16" foam wrapped around it as a plug. Once I had the sleeve I used that to trace out the shape onto pink insulating foam so that i could create two stiffening members for the cassette.
A layer of carbon uni and the cassette was wicked stiff. Now on to more fairing...
Yesterday, Traci and got the deck hardware fastened down. Guess who got to crawl inside the belly of the little beast to turn the wrench!
Lastly, today I got the rudder cassette partially faired and and dry-fit the tiller and fork to join the two. The tiller and fork pieces and down in the basement now marinatng in thickned epoxy (along with the cassette, which needed another coat of filler!).
So this week and weekend I did some gross tuning on the keel bulb.
I started out by drilling the holes for the cross bolts. I first drilled the recess for the bolt head using a 7/8" standard spade bit. Slow and steady is the name of the game when drilling lead. I know that other builders used loads of cutting oil, but I opted for water as I wanted to avoid extensive cleaning before trying to apply fairing filler. I also set the clutch on the drill to about half to avoid shearing off a drill bit. This worked great. After the countersink was done, I drilled a 7/32" pilot hole through the first bulb half. I then pulled out a 12" long 5/16" diameter brad point bit. With the drill on the low setting, small "bites" into the lead worked awesome. Pulling the bit out to clear it after 50 or so revolutions seemed to be the key. Once I made it through the first half, I laid the bulb over the keel foil to drill that hole, and then laid both on the second bulb half and drilled through. Finally, I drilled the counter sink on the other side.
If I had to do it again, I would have bought a long bit to drill a 1/4" pilot hole all the way through. With a 5/16" hole on the second half, it was difficult to drill the counter sink without the bit wobbling and I had to lug the 80-lb bulb half to my office to use the drill press. Incidentally, I tried a 1" Forstner bit on the second set of countersinks, and when using low RPM, it worked a treat.
OK, so the bolts are drilled and I am good to go, right? But, it turned out that the cast bulb halves contracted quite a bit as they cooled in the mold. This left the a 1/2" - 5/8" gap between the halves when I put then together. A preliminary weighing told me than I was also about 10 lbs below max weight. So I came up with a decent solution to fill the gap and add as much weight as possible. I started by folding a piece of aluminum foil into ~1" strips (probably 8-10 layers thick) and layed the Al strips onto the tacky side of regular old duct tape. I then used my homemade foil tape to create a dam to seal up the gap so that I could do a second lead pour.
My scheme worked great and the duct tape only melted a little. Best of all: no leaks! The second pour probably added about 8 lbs to the bulb weight and I am darn close to max class weight (185lbs for the bulb and keel strut).
I now have a coat of fairing filler on the bulb and fairing continues on the rudder, but it is quite close.
This weekend I had a go on the rudder and keel bulb.
On saturday I planed the shape of rudder from the laminated blank I made many moons ago. The keel was good practice. :) An electric planer is great when used with care. As with the keel I traced the profile on the ends of the blank and used the planer to "step" down the blank until I hit the line of the profile. I then planed those steps down until I had the foil nearly smooth. From there, I used the planer to cut a nice channel to recieve the carbon fiber lay up of stiffness. I saturated the carbon, layed it in the channel, and then smeared Microlight filled over the whole foil. Sanding to come...
I also poured the keel bulb yesterday. I have to note that Kevin and his wife gave Traci and I the best (my opinion!) wedding gift: an aluminum pot, an iron skillet, a ladel, and a bottle of champagne---all lovingly lead-tainted (maybe not the champagne). I must say, it was the only wedding gift which required hand-washing after opening.
I used Kevin's excellent blog post as a guide. The unseasonably cool weather this weekend (50-55F) and the wind made the job tough and Traci wanted NO part of the Great Lead Melting. Can’t blame her. :) So I was working solo. I think the temp and the wind made the lead slow to melt, so ultimately I ended up placing Kevin's aluminum pot directly over the turkey fryer burner, rather than on top of the iron skillet as he did. This worked fine, but by the time I was done the bottom of the aluminum pot had deformed slightly to match the grates on the burner. Careful if your pot is thin walled!
The pour on the first half was only OK. I don’t think I had enough lead in the pot when I started pouring, so layers started solidifying before I got the next layer poured. I have a couple of layers of lead that don’t seem well adhered so I think I will wrap the bulb with a layer of glass tape to keep everything together. It will also be bolted crosswise to the strut, so I am not all that concerned about the integrity of the bulb.
The second half went much better. I consistently kept more lead in the pot which meant much less time to melt additional pieces and therefore less time between ladlefuls of molten sweetness.
Interestingly (but not surprisingly) the second half, which I poured in a much shorter period of time, contracted significantly when it cooled. It ended up being a ¼” lower than the top of the mold and 6lbs. lighter than the other half (80 lbs.). I think I will get the halves bolted together and then try to seal the gap with heat-resistant mica tape and fill the gap with a small scale pour. Should get me up to weight, I think.
The i550 is a 18 foot sport sail boat. It is based on the sharpie boats of long ago and is built from 1/4 inch plywood covered in epoxy resin and fiberglass. The sail plan is in the "over canvased" category and should make for some fun sailing. The boat also features a bow sprit and flies a masthead spinnaker down wind.