Down For the Season

Unfortunately the sailing season is Montana is somewhat short, this does make for a good skiing though. Mothball One has been mothballed for the season. The last time I sailed I damaged the main foil again and found a crack the the mast base. Not huge problems, but I didn't have time to fix them and decided to just wait till the spring. The plan is to fix all the problems and have her ready to go when the ice comes off in April. It was a fun year, learned a lot, can't wait fly again, but flying over the snow has its merits too.

Good and Bad

Yesterday as a very good day for mothing. I finely was able to get the boat in good winds for figuring things out, 10-12 from the south and fairly steady. Everything went very well and I was totally stoked. I recorded 16.4 kts on the GPS for a max speed and sailed for about three hours. I went out again today in hopes of the same but the wind didn't come up at all till late in the day and then it was fairly puffy and shifty. I was working on handling the gusts and the boat was sailing ok, lots of steering errors on my part though, I need to work on that. Then bang! Crap. Look around and it looks like everything is ok but the boat is feeling really strange and won't fly so I look over the side and the daggerboard has split again. Damn. Better do a better job of fixing it I guess.

Little Things

I'm actually pretty surprised how well Mothball One is holding together. I have had a variety of breakages, buts its all been pretty minor stuff, not the huge splintering carbon fiber carnage I was half expecting to happen. I took the boat out last night for an evening sail in 10tks with some gusts around 20. That was by far the most wind I'd been out in, but she seemed to handle it ok. The boat foils great. Once its up it pretty much stays up till the wind dies or I crash. Unfortunately my sail was cut short by another small breakage. After crashing the boat in a gust I was arranging myself to bring it up and I somehow kicked the wand forward and broke the front rod linkage. Foiling over. It was a stupid little problem and a stupid mistake on my part for breaking it, but the linkage is probably under-built as well. So is the general rule just to stay away from the front of the boat in a capsize to avoid screwing up the wand? I'm also considering adding a rotation limiter on the wand to keep it from being pushed too far forward and stressing the mechanics. Little things, but I hope I can get them all sorted out and really start to learn this boat.

Flying Pics...Finely

It was a really nice weekend, just not a great weekend for mothing. It was hot and sunny but the winds were 3-5kts pretty much all weekend. Except for a brief period yesterday afternoon it was not possible to foil. But I did a bunch of lowriding practice which is probably a good skill to have. I must say that it is remarkable how much faster the boat is in lowriding mode when you disconnect the wand and reduce that AOA on the rudder. At one point my rudder came off, but I was able to reattach it with a bit of help from a jetski. Luckily I was able to take a few picks of my brother sailing late in the day when the wind picked up to a whopping 7 kts and the boat was just able to get foiling. Clearly the ride height isn't great, but that may have been due to the wind. I did extend the wand a bit today with a plastic spoon handle, but there wasn't enough wind to try it out. This week I hope to make a few modifications to prevent the tramp strings from breaking a keep the rudder from coming off again, but all in all the boat is working great. I can't wait to sail it in more than 10 kts of wind.

FIRE!

Tried to go sailing again today but the lake is on fire. Freek'n a man!

Design Notes

I wanted to write a bit about the things that I learned while working on Mothball in the next few posts so I'll start with materials. Woods is a great building material, its cheap and easy to shape and is quite strong. Wood is natural carbon fiber after all. If designed and used correctly its probably nearly as strong as a composite hull and nearly the same weight. So how come no productions boats are made out of wood any more? As far as I can tell its probably mostly to do with how long it takes to build a wooden hull. If you have a mold you can create most of a composite hull in a few hours with great consistency. A good wooden hull takes much longer to build and shape and will have natural inconsistencies. So the money saved in materials cost is lost in the extra fabrication time of a wood hull. If you have a ton of time and don't have a mold then a wood hull makes a lot of sense, but if you were producing hulls commercially a wood hull simply is not practical.

Carbon fiber tubes rock. They are actually really easy to work with. Just cut, bond, reinforce the connections and you're done. Carbon tape is your friend. Kevlar is nice, but is a pain to work with. Its really hard to cut and impossible to sand, well you can sand it but it always leaves hairs. Good old fiberglass is nice for doing finish work because its much easier to sand and finish than carbon.

Resounding Success!

Today was the first real day of sailing on Mothball 1 and I must say that it was a resounding success. After a marathon repair session yesterday we fixed all the broken parts and reassembled everything early this morning. My brother had to leave early so I let him go out first. I tried to follow on his keel boat but the motor crapped out so I couldn't take any pictures. He came back in and was surprised that the boat had taken off and foiled instantly. I was surprised too. He needed to leave so I went out on the boat and spent the next two hours on the water foiling most of the time in a nice 8-10 kt breeze. The boat feels great. Surprising good actually. The wand response is good, the rudder foil adjusts well and trimming the boat is easy, the rudder is surprisingly balanced, the rig works fine, and the only thing that broke is was one tramp string. I even tried to pull off a foiling jibe, it failed miserably but whatever. I was expecting to have major mods to do after the first real sail, but all I really have to do is inspect everything to look for problems areas and do some refinement on some of the systems.

First Flight

Mothball 1 has officially had her first flight, it was somewhat brief, but she did fly. I got everything rigged up this morning and hit the water early, the wind was pretty light on the first run and I broke some of the lines on the tramps so I went back in to fit it. When I went back out the wind was up a bit and I could tell she really wanted to fly. The rudder wasn't giving quite enough lift so I had to move way forward to get the boat out of the water but she finely took off and flew for about 10 sec until I ran out of lake. I tacked and headed back the other way and she took off again and really started moving. Everything went quiet and the rudder got really sensitive but she was off and she felt good! Then POW! The sound we all hate to hear. The boat crashed back to the water relatively smoothly and I kept sailing trying to figure out what had broken. The foils were still on, the rig was up, everything was in its place, but she clearly wasn't interested in going onto the foils any more. A brief inspection at the dock revealed the problem, the daggerboard had separated down the middle. Apparently I hadn't bonded the two sides together well enough and it just cracked. Luckily there wasn't any major damage. Spent the last four hours re-bonding the sections and its back out to the lake tonight. I'm kind of amazed this thing actually flew without making any major adjustments on the first day! Yay!

Moth Lube?

The SS rod is done. All thats left to do attach the rotating pin in the flap and do final adjustments. Friday will be the day for the test flight. Yay. One quick question, is there a recommended lube for all of these moving part?. Everything on the boat is reasonably low friction, but I figure lube is always good. What do people generally use for lubing the push-rods and such?

Foiled Again!

For a variety of reasons, my goal of foiling this weekend will not be accomplished :( There are several reasons for this, not the least of which is the fact that the guys at the machine shop did not come through with the parts, but its also the July 4th weekend, my daughters birthday, company is coming, bla bla bla, so maybe this is best anyway. The good part here is that instead of rushing the last few jobs and then splashing the boat I should be able to do a bit more refinement over the next week and I promise next Friday will be the day. I even ordered some additional fiberglass rods yesterday to ensure that I will have a functioning push-rod available by the end of next week. The glass rods may not be as good as a stainless ones, but it should be good enough to last a day of beginner mothing if needed.


But speaking of foils, check out the mostly finished products. They still need a small amount of fairing and need to be pained, but should be quite functional and honestly look quite nice. I added the bullet on the main strut at the last minute, but it turned out really good and should help make the joint stronger. The thing seems pretty stout, I didn't test it to destruction but I pulled on the ends pretty hard and it gave no sign of even flexing. Do note that the rudder seems to be slightly longer than the daggerboard, this was just a function of how they got assembled. Once installed on the boat the foils will be pretty much in line going through the water. The rudder foil is currently screwed on so I can change the length if necessary. Does anyone have an opinion on having the rudder slightly longer or shorter than the daggerboard?

OMG Close!

The machine shop claims that the push rod will be done tomorrow. Yay. Today I finely broke down and created a test push rod and crank connector. The connector was plastic and the rod was taped together in the middle, but it sort of worked and let me align all of the components and then bog the sides of the board together. Tomorrow morning I attach the horizontal, do some reinforcement and some finish work, go and pick up the push rod (fingers crossed), and get ready to splash this thing!

Bladerider Copy?

So I started thinking about Mothball 1 and I realized that this thing is pretty much a Bladerider. I wasn't intending to do this but it just kind of turned out that way. I got all the parts randomly over several year but they all ended up being bladerider bits. Maybe this is just because that's all that was really available. Sail - Bladerider X8, mast and boom - C-Tech, rudder horizontal- Bladerider, Mechanical bits- Bladerider, the boat geometry is similar to the Bladerider, the total weight is almost the same, the only big difference will be in the main lifting foil. Will it perform like a Bladerider? Probably not, but it should be close.

Waiting isn't all bad

The good thing about being forced to slow down on a build is that it gives you more time to test things before they get put to use. When I assembled the boat I jumped all over on the tramps and the small carbon connector rods I was using started to explode. They were clearly not up to the task. Not hard to fix, but I was glad to have broken them on the hard rather than the first time on the water. I also decided to change my wand geometry slightly to reduce friction and eliminated some play in my rudder adjuster. All of these things should make the first voyage go much better.

The Finish is Near

Spent most of the day doing misc. finish work on the boat. This thing is nearly done. I have a variety of small items left to finish, but it could be operational in a matter of hours... if it weren't for the FREEKING daggerboard. Sigh. The daggerboard is still in many parts with a few critical components missing, namely a 2mm push rod. I'm doing my best to get one made and I have another on backorder, but still no luck. I don't want to assemble the daggerboard without it, cuz if something doesn't work when I insert the rod, I'm totally screwed. So instead I'm waiting and waiting and waiting...

Pressure Testing

Leaky boats are bad, but how do you know your boat leaks before you put it in the water? Simple, a bike pump, soap, and water. You plug the bike pump into the hull and then use the soap and water to test suspect areas. If the suds blow bubbles, its a leak. Using this method I think I found at least most of the small leaks. It won't hold the pressure from the bike pump forever, buts it clear that Mothball is fairly watertight. I was also able to get the rig up with the sail on to begin testing on the running rigging. The goal is to splash on Friday. Wish me luck.

Supertramp!

They really are super, nice fit, a bit of finish work still, but clearly functional. A big thanks to my dad for helping design and sew them.

Almost There

Did a lot of work on the boat this weekend and I'm happy to say that its getting pretty close to done. This weekend I sewed the tramps, faired the hull, got the rudder adjuster up and running, made progress on the rudder gantry, and started the daggerboard box. There is some finish work to be done on all of this stuff, but I'm happy with where everything is. The only outstanding item is that I still do not have the 2mm push rod for the daggerboard flap. I may end up needing to build one, but that wouldn't be too tough. I'll work on getting some pictures up tomorrow.

28 lbs

Weight is everything on the moth. Heavy things don't fly. I've been trying to get a handle on the boat weight for a while but frankly I couldn't find a good way to accurately measure it, until today. With the aid of a few pulleys and some weights I was able to suspend the boat and check the hull weight. It turns out the total weight of the mostly finished hull is 28 lbs. I still need to do a bit of fairing and paint it, but 28 lbs is actually quite good for a home-built plywood hull. It is about 10 lbs heavier than the Mach 2 (~18 lb), but its significantly lighter than the Bladerider FX (~40 lb). This thing may actually fly.

Getting Closer

So I have been slowly progressing on this thing, but running a business, taking care of a two-year old, getting a keel boat ready to race, planning a national regatta, and building a Moth takes a lot of time. I'm not complaining, its all fun, its just hard to focus on one thing. Anyway, here's were we are. I have almost all of the parts finished for the rudder and tiller assembly. The rig is pretty much done. The hull is mostly done but needs to be faired a bit and painted. I'm waiting on some parts so that I can finish the daggerboard and main foil and I need to sew the tramps. I also need to get the misc. hardware and get everything mounted on the boat. And I need to build a dolly. It's really just a lot of little stuff at this point and I'm still hoping to be sailing in a month, but tomorrow its off to Seattle for the NOODs!

Holy Epoxy Batman

So here is the Bladerider foil that I'm fixing up. I drilled two small holes in the foil where the core was crushed and started dripping in epoxy. And OMG did the epoxy flow. I had to go back to the garage three times to get more epoxy. It took twice as much epoxy as I was expecting to fill in the void. It seems to have done good job though.

Foils, foils, foils

The foils are all here. They all need some work, but at least they are here. Lets start with the rudder horizontal. This is a nice Bladerider foil that got into "an incident with a power boat". The tip of the foil got cracked and the foil is scratched up quite a bit. Originally I was going to just put some extra carbon on and call it good, but now I have a better idea. The damaged area was very compressible and seemed like the core must have been totally crushed. So instead of reinforcing the outside I'm going to drill into the the foil and then inject epoxy in to replace the core. Then with a bit of fairing and some paint it should be good as new.

The rest of the foils will take a bit more work. They should turn out great, but they are less than completed. The foils are in two halves at the moment. The main foil and the rudder foil came out of the same mold, the only difference being that the main foil is constructed with more carbon than the rudder. I'm going to try and fit the rudder foil into the Bladerider socket. All I should need to do is shape the end and fit a bolt into it then attach the two halves.

The main foil will be a bit more involved. The main foil need have a bunch of mechanical bits fit inside of the foil. At this point I'm not even really sure how to make this happen. Better call Gui.

More Progress

So there isn't much new as far as assembly goes, but lots of new on the parts front. New just today, FOILS! Holy crap Batman. I can hardly believe that I actually got foils, and I didn't even need to spend a fortune to get them. Granted they are not totally finished and will take a bit of work get them ready for the boat, but they look really good and should work great. I was talking to fellow moth home-builder Gui and he had a set of unfinished foils that he didn't need. He's a great guy and ended up selling them to me for just the cost of materials. However, he didn't have a rudder horizontal foil so I needed to find one of those. I send out a message on the US Moth groups page and found a slightly damaged bladerider foil that I was able to purchases very inexpensively. I also purchased some kite tubes to use for some the control rods. As soon as it warms up a bit things should start coming together fairly quickly.