Current Build Status

Ok, so after my long delay in progress I'm getting working again and things are moving right along. I'm actually pretty surprised at how fast things are going at the moment, but with the hull and racks mostly completed, much of the rest is the small detail work which is fairly easy In the last week I have in installed the compression struts to the mast post and am currently working on the rigging. The components of the rig are as follows:

• Mast Base
• Boom
• Spreaders
• Shrouds

Having completely blank tubes from which to build all of this stuff has given me a lot of freedom about how to put it all together. Lets start with the mast base. This part is pretty easy. Its two chunks of delrin that are cut to fit in the mast post and the bottom of the mast with a cut-off bolt head to act as a pin. The hardest part about this was finding the delrin, which I ended up getting off of E-bay. I will have the delrin lathed to fit the two end.

Boom - pretty easy really. Just cut the end of the boom to fit around the mast and then attach it with a bolt. I also have the hardware pieces for the vang and outhaul on order.

Spreaders - I spent some time with some scale drawings trying to figure out the perfect geometry for the spreaders. I think I'm pretty close, but I'm going to build a set of test spreaders that will have a variable geometry so that I can test them a bit before I build the real set.

The mast attachments will be made of solid carbon and are pretty close to being ready to put on the mast. Once these few things are done I should be ready to put the rig up and start testing it out. Once I get everything how I like it there will be some finish work to do, but I have all winter to do that.

Progress, OMG!

Wow, has it been a year since I've posted? I guess it has. After dealing with a bunch of happy horse $hit over the last year, work on Mothball one has resumed. I'd almost forgotten where I was, but now that I'm going again I remember how much fun this project really is. Hopefully over the next month or so I'll get a lot of stuff done and have the boat ready to go in the spring. More updates to come soon.

Hey, it looks like a Moth!

This thing is actually starting to come together. The racks are assembled and most of the hull is done. I need to re-inforce the deck with a carbon/kevlar fabric and do some extra finish work inside the hull, but its just about ready close up. After that I need to finish the mast support and then tape the outside joints and it will be time to think about fairing and painting the hull. I'll probably wait a while to do that though.

Some fun notes about racks, building them off of the boat is the ONLY way to keep them square and I think I did a pretty good job. It is a little scary putting everything together on the floor and then hoping that if fits on the boat. To this end I didn't reinforce the angle in the carbon tubes until I checked that it was all going to work. This was probably a good plan, but it also lead to several joint failures while moving things around. They were easy to fix, but it was a bit un-nearving. Another note, the rack frames are quite large when assembled. The frame is close to seven feet square. Once its on the boat its fine, but its really hard to pick the entire frame up just because you can't reach very much of it at a time. I am really glad that I made the frames collapsible.

Racks!

The racks are coming together. This is somewhat of a slow process with lots of little pieces needing to go together in a particular order. The racks will be removable from the boat and will be collapsible for storage/transport.

A few things I learned so far about racks. They are not easy to put together. First they need to fit on the boat, and they also need to be square, and they need to be solid. My method for attaching them to boat should work fairly well. First I made the crossbeams and attached them to the boat where I wanted them to be. However, its really hard to make them square on the boat, so I needed to remove them from the boat to square everything up. Then it will be back to the boat to re-attached them. It sounds a bit weird, but I really couldn't think of another way to do it. I'll post some pics once all the parts are attached.

The racks are solid carbon and should be really tough once I get done with them. Strangely I had to purchase almost no carbon tubes for this project. Some people have random 2x4s in their garage, I have random lengths of carbon. I purchased the big tubes years ago with the idea of putting racks on my I-14, never got around to it. The cross tubes I purchased for almost nothing a long time ago, just because they were a good deal. I used a few of these tubes over the years and had just enough left for this project.

One more note of interest. I don't intend to attach the racks pieces in any permanent way. The big bars will have stubs which will slide into the cross beams. Then everything will be held together by the tramps. I'm going to use a few tricks to keep the parts from rotating or moving at all. Hopefully it will be really solid.

Interior Structure

Here is the interior of the boat. There is a bit more work to do here, but its getting pretty close to done. Once the interior is done all I need to do is put the deck on. I could do that pretty soon, but I'll probably leave it off till I get more parts finished, cuz once its on, there is no opening it up again.


In the middle of the boat you'll see the daggerboard box. The box is made out of plywood with a layer of carbon inside of the box for added strength. Note the tabs along the end of the box (they are covered with a bit epoxy). I made the box with these tabs on both side so that the box could be assembled with precision inside the boat and then bogged in place. As anyone who's worked with epoxy knows, lining up parts can be tough when gluing multple pieces together. The tabs on the box were aligned precisely so that it could only fit together one way.

You'll also notice that the box is slightly larger than it needs to be. Infact its 1" x 8" which is much larger than any modern daggerboard. But since I don't have the foils yet I made the box larger than necessary so that I can finish the boat without having my foils and know that I can make anything fit. Once I get the foils I'll make and insert for the box that will exactly fit the foils. This way I can also change foils in the future without much trouble.

The 11'3'' Moth

Here is the bow of mothball1. How did the end get blunted so well? Originally the boat was 11'3'' by design, even though the hull can only be 11' 0'' by class rules. In order to keep the lines constant I made the boat slightly longer and then inserted a shaped piece of wood at 11' exactly and then cut the last three inches of the hull off. This will make a very tough and nicely rounded nose without changing the lines of the boat. I think it looks pretty good. a sharper nose may be slightly faster, but its also more vulnerable and decreases the volume in the front of the boat. One of the realities of the hydrofoil boat is that maximizing displacement mode boat speed is silly. Once you start to exceed hullspeed you will by on the foils so it doesn't really matter how fast you can go while lowriding. Its better to make the hull more functional for lower speeds than maximizing displacement boatspeed.

Home Sweet Home

This was a good weekend for Mothball1. Not only do we have some of the internal bulkhead bogged in place and the deck shaped, but I also transported the boat back to my house. The ride home was a bit more eventful than I was hoping. About ten minutes after we left with the boat on top of the car we drove through a fairly large rain and hail storm. There was nothing we could do about it so we just kept driving hoping it wouldn't damage the raw wood on the hull too much. After we stopped I inspected the boat and found no hail or water damage at all. Yay!

Having the boat at home should speed up the construction process considerably. There is still lots to do, but with the boat in the garage I should be able to spend a lot more time working on it. I spent a bit of time sanding on the bottom of the hull and it turns out that the major screw-up that I did at the beginning of the project isn't going to take that much to fix. A bit of sanding and some filler should fix most of the problem areas. The boat should begin looking very Mothish over the next few weeks.