• 3rd December 2009 - By greg

    Ventisit seat pad

    After my last blog post, there was some discussion about leaving some air space below my sleeping pad to allow condensation and water to collect. I wanted to expand a bit on that with additional photos and details on an amazing find that I made of a new product from that bike crazy nation – the Netherlands. It’s called the Ventisit seat pad. I found this cool little company because I had used one of their recumbent seat pads in the past and I liked it so much that I contacted the owner Bart van Crasbeek, and asked him if he would be interested in building a custom sleeping pad for WiTHiN.


    Ocean Sleepware sleeping bag

    The big advantage of this product isn’t so much the soft padding it provides to cushion body parts, but the large amount of space in the plastic mesh that allows air to flow through. I use a thin, 1/4″ thick single layer on my Nocom lowracer seat and my back stays dry even on the hottest day. It doesn’t provide much cushioning, but I find that cushioning isn’t really required if the seat is designed properly, and there aren’t any hard edges pressing on the skin. Flat, smooth and hard is fine as long as your weight is evenly distributed across as much of the seat as possible, and you can get some air flowing between your body and the seat to stop moisture from collecting. This is what the Ventisit pad was designed for.


    the air matress and my immersion suit


    Ventisit sleeping pad under the immersion suit

    My sleeping mat is 4 layers of Ventisit mesh that is wrapped over itself like an envelope so there are no sharp edges. Water poured onto the pad simply falls through the mesh and collects on the floor keeping the mattress or sleeping bag dry. It’s not soft enough to sleep on though, and I am experimenting with a camping air mattress, and a Thermarest. The Ventisit pad provides good cushioning for sharp body parts like elbows and knees, but when lying on the pad, it doesn’t form enough to sleep comfortably.

    I also use a double layer of this mesh on the recumbent seat in WiTHiN. I opened the ‘mesh bag’ up, wrapped it over the seat and sewed it up again. Since the sharp edges of the plastic mesh wrap around the edges of the seat, there are no abrasive edges to scratch me. It ends up being just soft enough, but more importantly, it really encourages air flow to keep it dry. It works better than anything else I have found so far.


    Ventisit seat cover on the recumbent seat

    Shown below is a photo of the keyboard holder that I made. It’s an expendable shower curtain rod with a Sintra plastic mount that I made to hold a keyboard. the keyboard is a water proof ‘ReallyCool’ keyboard from sponsors RuggedTech. I can move the keyboard holder to a variety of locations in the cockpit or cabin. The reason I did this is because I plan to write a bit while on the ocean, and I really wanted a decent keyboard.


    keyboard and iPod mounts

    The screen that you see in the photo is an iPod Touch mounted on a Ram Mount that conveniently swivels easy viewing. There is a second Ram mount in the sleeping cabin. I’m planning on loading videos, movies, TV shows, and documentaries onto a 64 gig iPod Touch that will hold about 80 hours of video. The iPod is secured in a water proof OtterBox case. I will also take a second iPod Touch and iPod Nano that will contain a decent collection of audio books and music.

    When I write, I will be replacing the iPod touch with a hand-held PC called a Viliv S5 pictured here which runs full Windows XP OS – not Windows Mobile. I’ll be connecting the S5 to my Iridium Satellite phone provided by PTO sponsors Satellite Phone Store to transmit and receive emails, send blog reports and photos. The S5 also features a built in GPS which I can use as back-up, or when my power is low and I have to turn off the larger RayMarine GPS.


    The Viliv S5 hand held computer

    The slick piece of software that I use to send blog posts, photos and email is from PTO sponsor UUplus. UUPlus software achieves throughput speeds four or more times faster than standard POP/SMTP connections and twice that of general purpose accelerated gateway software which makes it perfect for use when sending and receiving data by the Iridium satellite network. UUplus is available for both the Mac and Windows, and I had a chance to test it out when we were on Okanagan lake with my Macbook. It took about 2 minutes to transmit a photo and blog post which is pretty efficient. My Iridium air time for that minute cost me only about a $1.25. Not bad. Here is that blog post.

    And this final photo is the new keel bulb from Manny at Rohmec Industries. After the Vancouver Island sea trials, Jordan and I felt that WiTHiN needed a bit more ballast in the keel to allow more stability while standing up through the hatch. The old keel bulb was about 40 pounds, and this new one is 90 lbs (placed 3 feet below the hull).


    The new 90 lbs keel bulb

  • 10 Comments to “The sleeping cabin, and some cool technology”

    • Bruce Bolster on December 3, 2009

      Hi Greg:

      Wonderful cabin layout, great electronics and ergonomics. I would give the drive leg, rudder and hull below the waterline a good coat of copper-based antifouling before departure to keep the barnacles and other marine life from becoming attached. I use VC-17M on my racing sailboat, it has both copper and teflon-based antifriction compounds- gives you the protection you need plus a nice slippery surface.

    • Martin Greiner on December 4, 2009

      On the cushion question: some really great, highly breathable padding used in wheelchair seat cushions. This stuff not only has hex-holes going through it, but lots of small holes going sideways. Multiple densities/firmnesses available. Check out their website:


    • David Tangye on December 4, 2009

      The Ventisit sounds excellent.

      All the comms and geek stuff is certainly a change from my times offshore, before the internet and satnav. We had RDF and a sextant, and lots of peace and quiet. It was great to not have any artificial noise at all, except running the engine now and then to charge battery. Captain Cook’s sailors were the true offshore mariners though: not even any charts in many places, unless they created them as they went!

      Antifouling: Dunno if Roz Savage and others used it, but I certainly thought they should have. Their hulls seemed to get quite dirty quite quickly, and a bit of slime slows you down a lot. A clean while swimming would certainly help.

      Keel: 40lb to 90lb is a huge change. As I am sure you know, it will sink your waterline and slow you due to the extra wetted surface. Also, I hope it does not stress the fin and through-hull area too much. Its already a high aspect, high stress setup.

    • Henk on December 5, 2009

      Almost the same material as Ventisit (but much cheaper) is this: http://www.svb.de/index.php?sid=f4ed57c2c22e2fae5b5d7e6bbb6b0067&cl=details&anid=2175&tpl=&lang=1&listtype=search
      I use this on my recumbents. Can be cut to size with scissors.

    • Brian Salter on December 6, 2009

      Did you give any thought to using a hammock-like contraption for your sleeping comfort? A hammock is lightweight, would keep you dry, and can be remarkably comfortable. I’d suggest using bungees to attach it, so as to get some isolation from the motion of the boat.

      For my rowing, I prefer a “yakpad”, a gel-filled seat cushion. While you might tend to have more moisture-based problems, I find that it does a fine job of keeping the ol’ backside cushioned, even after long rowing sessions. I’ve got about 4000 miles on mine with no signs of wear.

    • DD on December 11, 2009

      Looks very good Greg!

    • Mike on December 31, 2009

      Would a hydrofoil be of any use for your boat ? I have seen it used on other human powered boats to raise the boat out of the water for greater speed with less power because of less drag – like in the following link:

      btw, if visibility is important, you may want to paint the craft bright orange.

      also – from the pics, it seems there is still some space left for more solar cells.

      good luck on your voyage !

    • Wheelchair Cushion Sage on January 1, 2010

      Martin Greiner – Thank you for your Dec 4, 2009 reference (above). As you noted, the honeycomb cushions permit a higher degree of air circulation than most other types of cushions. Additionally, it is the perforated, open cell honeycomb structure that makes this type of cushion ideal for wet environments – it dries quickly compared to other types of cushions.

      Greg – would you be interested in getting/using one of these cushions sized just for you as a something like a sponsorship for your adventures?

    • Jason on February 15, 2010

      I am a nobody, just an interested person. what is the construction of this boat? Looks very intelligently designed. My concern the small keel, the length of the boat rolling over 8 foot swells and the nose constantly slamming down, and worst case scenario if the boat was to break in half how easily accessible is the life raft underneath while sinking getting banged around and hanging on to a satellite phone. Is there food in the life raft? would the life raft be better stored on top outside? should the phone be in a waterproof case attached with a cord to your wrist in bad weather. I look forward to staying tuned to this neat adventure.

    • Berry Secore on April 6, 2010

      You could try & Hold your iPad for No cost! -> http://bit.ly/cFBuis

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