• 4th May 2007 - By adventuresofgreg

    Wow – did I ever get a lot done over the last few days. Dare I say that I think WiTHiN is just about ready for her maiden voyage?

    The first thing that I wanted to do was to fair-in the drive leg gear box. The amount of drag from that square, chunky box behind the prop is probably substantial. However, before permanently enclosing the gear box, I knew I had a bit of work to do on it. First off, I chopped off the large square steel tube that was used to mount the gear box to the drive leg struts. I cut half of it off to a much lower profile. Then to add some strength to the connection, I welded two nuts to the cog housing so that the gear box was now being held in place with 5 bolts from two angles.

    Next was to re-build my little 11 tooth cog. The grub screw holding the gear onto the axle needed to be an Allen screw so that I could get access to it with a small, right angle alley key. this would allow me to pull the cog off the axle if I needed to, without having to first remove the entire gear box. So, I decided to build a brand new cog using this 1/2″ collar with a Allen screw set screw built into it that i had picked up from the hardware store the other day. This fit perfectly over the axle, and I had a washer that I welded onto the collar and then welded a new 11 tooth gear onto that. Perfectly CENTERED. My old one was a wee bit wobbly because I couldn’t get it to center. This one works much better.

    Then, I made an access plate that is held on with one screw and siliconed around. I bolted it all together and siliconed all of the joints.

    Then, to make my fairing, I made a card board box, suspended the drive leg in the middle of the box and poured two part expanding foam into the box. When the foam dried, I ripped off the cardboard and proceeded to sculpt out a nice tear drop shape.

    After i was happy with my sculpture, I wrapped it in a few layers of fiberglass, then whetted it out with epoxy and wrapped in in stretch seal to cure. I sandwiched it between two flat plates and 75 pounds to make certain that the exact width was the same as the drive leg bay (or I wouldn’t be able to get it in or out!).

    After it curred, I coated it with Bondo and sanded smooth.

    Since the gear box is water proof, and since I have sealed all of the joins, gaps, bolts, etc with silicon, AND covered the whole unit with foam, multiple layers of fiberglass, soaked in resin, then a Bondo otter coat, it ‘should’ be water proof.

    The next thing I did was coat the rudder with micro and sand smooth.

    Then I re-built parts of my steering mechanism. During the pool test I noticed that the threaded rod connected to my steering tube was flexing a bit and also rubbing against the side deck. I also noted that during a hard turn, my handle clamp would slip. So, I added a pin to the clamps on my steering handle and the clamp on the rudder steering tube in the back. I also replaced the threaded rod with a stainless steel tube.

    The very last item on the list was to install my soft decking. I am using aircraft wing material called SuperFlite Light fabric – like Dacron. I bonded the fabric to the gunwales of the bow and stern compartments using contact cement. Then I used a hot air gun to shrink the material tight. It came out really sweet – like a drum!. I made a small test piece and poured water on it and it leaked like a sieve. Darn. So, I called my local composites shop, Industrial Paints and Plastics and asked what I could paint the Dacron fabric with. He said he has customers painting sail cloth and fabric wings with a water based marine polyurethane top coat, so I ordered some red and painted the decks.

    Now I need to dust off my two way radios used for the 24 hour HPV record in Eureka, and my wicked powerful HID headlight that I used for the failed 24 hour record attempt in Alabama. The HID headlight will be necessary to see where I am going in the dark hours on the lake during the 24 hour HPB record attempt 4 weeks.

    I think I’m in the lake on Sunday. If you are local, and want to
    come out, then email me for details.

  • One Response to “Loads of work completed”

    • Steve on June 14, 2010

      I am an engineering student, and I am working on a project very similar to you (an ocean-going pedal powered boat). So far it is only being designed, and I am not yet sure if it will be built. If you don’t mind, I am wondering about your drive train: I like the design you have constructed, but I am wondering how you plan to replace broken and worn-out parts during the crossing. Are you using special corrosion-resistant parts and materials?

      All the best with your adventure!

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