I've made loads of progress on the Corbie 5 since my last post. Most of it has gone well, but I've had a few not so good things happen too. I've finished the fin box and installed all the bulkhead work around it. It looks like a lot, but doesn't weigh toooo much. It should keep the fin in place though, and it includes a raked mast step slot, a rudder servo mounting plate, and a winch mounting plate. These two images show the deck just sitting on top. You can see how much access there is to the winch and rudder servos. Should be OK. This picture shows the shroud chain plates being epoxied in place. I'm a bit concerned that they won't be strong enough. I'm used to "locking" in the chain plates mechanically by slotting them into nearby frames. This seems to be the way it's done though. Gulp. I used a good amount of thickened epoxy, so fingers crossed they'll hold. When I installed the fin though, I noticed that it...

Yikes... I'm really in uncharted waters here. Not only is this my first IOM, but it's the first part of the build where I've really been on my own to figure it out. The pros who have been helping me simply buy theirs pre-made and install it.  Did I do that? No, of course not. I bought a fin and bulb and that's it. Pay $140USD or more for a fiberglass fin box? How hard could it be...? Well, I'm not done yet, but so far I think I made the right decision. No, it doesn't look as nice as the pre-made ones... clearly! But it perfectly fits my fin and I made it myself and it was cheap and it should work and I don't care what else you say! Here's how it looks tonight...  Here's what I did. First, after carefully mounting the fin to the bulb (see previous post), I was then able to carefully measure and cut my fin using my laser cut fin box template. I cut it almost perfectly using my tablesaw which made an extremely clean cut. Then I taped up ...

I've been working on a number of different things on my Corbie 5 IOM this past week. This post is on how I aligned and fixed the fin and bulb to each other. First I used my IOM Alignment and Measuring jig. It worked well! See earlier posts for more info. I spent a lot of time lining everything up as best I could. The Corbie 5 manual says to have the front of the fin at 493mm from the stern, the fin raked so that the base is 6mm aft of the top, and for the center of balance of the bulb to be 10mm aft of the leading edge of the base of the fin. I then worked on the bulb. It weighed well over 2500g when it arrived, and I had to remove a lot of weight. First I had to hog out the channel so that the fin would fit. I used my drill press to hog out much of it, and then my Dremel tool to remove the rest. I also drilled out the mounting holes. This bulb came with a large brass insert that had a 1/2" base and a 5/16" sleeve. I had to use two different bits to get th...

I need to start to consider how I'll mount the fin and bulb, and get it all straight, so I made a 3D modeled alignment jig: Ian Dundas in Scottland sent me pictures of his setup. I just bought a laser level too! He does amazing work and has been a great help in this project so far. There is also another jig featured on page 14 of the winter 2008 Canadian Radio Yacht Association (CRYA) newsletter that features one. It's by Lawire Neish. Read it here . I took both those designs and made my own version that features sliding cradles for the hull, a fixed waterline sight, proper depth to cradles for the bulb, etc... Most of the parts can be laser cut, and the two end pieces and the base can easily be cut on a tablesaw. It has fixed waterline sights that are 420mm above the top edges of the bulb sliders in the base. The fore and aft cradles can be slid up and down to adjust the waterline of the hull. You'll see that the overall interior length is 1003mm t...

Found some time to work on the frames for the Corbie 5 IOM RC sailboat. Changed the aft deck arrangement... more on that later. But most of my time today was spent working on the fin box area. I'll make my own fiberglass fin box to exactly fit the fin, but that won't be sufficiently stiff enough, so I made a 1/16" ply box that I can use to support the fiberglass box. I won't "fill" the box with thickened epoxy, but will use it in areas to bolster the pressures. More in January when I can return to this project. Happy Holidays to everyone!! Aloha!!

I finally received my new IOM fin, bulb and rudder today! It was shipped from Australia from Radio Sailing Shop . So far they look great, but to be honest, I'm not entirely sure what I'm looking at. The IOM fin is long, thin, carbon-fiber, and very light weight. It only weighs 101 grams! This isn't the way it is in Vintage Marblehead or Star 45's. The rules say that the fin and bulb together can only weigh 2500g. The bulb is currently 2533 grams and it will need to be worked a bit to get its weight down. I intend to epoxy coat it and then paint it as well, so that will add a small amount of weight. There are clearly some parts of the bulb that need to be cleaned up, but overall it's a very nice mold! The rudder came with a piece of 4mm stainless steel shaft, but I'm going to use 1/8" stainless steel. 1/8" is 3.175mm and is plenty strong for both Marblehead and Star 45 rudder posts, so I'm pretty sure it'll hold up to this. 1/8" ...

It was suggested on RC Groups in the " Vintage Marblehead Resurrections " discussion page, that I ought to not extend the fin deeper than the original. The other day I posted my updated Rip Tide HF (High Flyer) design with a 16" draft. Here is how it looks with the original 13" draft. As a comparison, here is my Rip Tide HF version with the 16" draft fin.  If interested in building a modern version of the 1949 Rip Tide, please let me know. I'm close to completing the file to cut laser-cut frames. After a few months of work and tinkering, you'd end up with a beautiful wooden radio-control sailboat. More later! Peace!