Warren Beauchamp's recumbent bicycle and human powered vehicle (HPV) web site!
Balsa-Wood Fairing Concept

May 2015 - A project by "HPV Of Earth" 

I used cardboard a lot to help me visualize what shape the fairing might take and to help point out possible problems.
In the past I have made complete fairings out of cardboard to see how it would work. With this fairing I used the cardboard to visualize edges and ribs that hold the skin/body of the fairing. I used a lot of cardboard in the design phase.

I've made a fairing using Styrofoam and fiberglass and this method is a whole lot nicer. The waste is easier to deal with using balsawood as the building material and cardboard as a design aid. Fiberglass and Styrofoam are very messy and leave nasty waste.

Interferences are things that HAVE TO be designed around. The cardboard helps in seeing problems and solutions. For example I would clip a shoe in the pedal to help see where things could and could not be. When I made the ribs I did the same and sat in the trike to see where things like knees might hit and where not to put the ribs

the following pictures I hope will show how it went from cardboard to ribs. The ribs have to be attached to the backbone yet not interfere with the moving body. Use of the cardboard helped decide were things would be glued on and sometimes showed were errors made that hade to be designed around..

 

The image to the left shows the "back bone" of 1/2" thick balsa along with more cardboard being used to aid in design. The cardboard can be drawn on and cut many time before it becomes useless and the cardboard is easily recycled or put in compost bin.

I like it when waste or trimmings can be placed in the compost pile or otherwise be easily recycled. I have made things using Styrofoam and it creates a lot of hard to retrieve Styrofoam waste that clings with static. This is very much less of a problem with the balsawood and I do not care as much if it blows out into the yard or street unlike the Styrofoam.

The nose shape I decided on was defined by ribs which were made from 1/2" thick planks.

On these ribs I glued thick blocks of balsawood that I then cut rasped and sanded to shape. When holes appeared because I rasped too much off I filled in the hole with scrap and then cut, rasped and sanded the scraps.

For the most part I like the way it turned out and the nose seems stout and it is capable of carrying light loads like bread when the rear carriers get full.
 

Nothing was certain until it was done.

At the start of the faring idea I thought that it would come to a point at the nose and it was not until I came to the point of finishing the nose did I really think about adding a light.  A place was also left under the fairing to add a light. I knew I wanted more lights but again until they were in I was not certain how they would be added.

The lights are not too difficult to get to but I can not get to them without lifting the top up.

The pictures I hope show how I glued blocks together around a frame and then sanded/rasped material away to give the shape. When small holes appeared I filled them in with scrap balsa then cut and sanded the plug to shape

In the image to the left you can see were I made an error in design in that there is interference with the pedals as the front lifts up and open. this causes some minor problems if I get in or out and the pedals are in such a place to interfere with opening .The only carbon fiber piece is that which is barely visible holding the fairing

The nose of this fairing is pretty much done in this image and from here I added the sides and top that made up the body. The sides and top were made from 1/8" thick balsa planks glued to the "ribs". In the image below you can see the ribs that the side and top were glued to in order to make the body. If I had planned things I could have used that method to build the front and save a great deal of weight.

The nose is strong but heavy, at least five pounds 

I did a lot of staring at the fairing as I was making it, as nothing was absolutely determined until it was past done. I was not sure how some things would end up until I was done.

The lone piece of balsawood at the end of the balsawood backbone is not glued in in this picture and I used it as a visual guide in determining  how to proceed. The limited supply of balsawood on hand added to the design

 
  With limited balsa I staked pieces on to see where I could cut and fill to maximize coverage with what I the balsawood I had at the time.

I used clamps and tape to hold the planks in place as the glue dried. I glued one plank on at a time then added more planks to fill in.

When I was done I sealed it with a clear paint and some thinned epoxy. It remained a uncovered balsawood for some time. I was thinking at the time but didn't add side wheel/hand wells on the side. instead I covered it before I added the wheel well hand warmer thingies

 

Initially I used some blue vinyl heat adhesive car covering product that I saw on e-bay. The blue color on it faded fairly quickly to a purplish color. The chameleon blue to purple stays the same color but is wrinkling and splitting.

I no doubt did not apply it correctly as it is heat applied and I was applying it to balsa wood. I was going to paint it but thought that this stuff would add better weather protection. You can see how much the color has changed from deep blue to light purple. That vinyl stuff has shrank, split, expanded and wrinkled no doubt due to poor application by me
The two images above are about six to nine months apart and show a little bit how nice it looked when just finished and some of how it has wrinkled and split since. The top is a chameleon and it is the same as is on part of the "trunks" panniers and you can see go from blue to purple. There are parts seen in the right made from colored craft paper found at a local dollar or less store. I use that a lot also in the conceptualization of things. Craft paper and tape fill in the gap between the seat and the rear panniers / trunk. I believe that it is poor application by me that has caused the vinyl stuff to wrinkle and split. No instructions came with the stuff that cost more to ship than the winning bid.. It is intended for automobiles and not balsawood but I could have done a better job ironing it down.

I added side wheel well thingies because in the winter, spring and fall it can get rather cold in the morning and the wheel well things keep my hands out of the cold and possible wet weather.

The top keeps my head out of the sun which is nice on hot days. It was added at the same time as the wheel well hand well things. I made mo9re than one craft paperboard wheel well things before I finally made one

Next you can see how I made ribs that were glued to the balsa wood skin and how 1/8" thin balsa wood planks were glued to the ribs to skin it.

I hope these images have helped you some. The arrow above points out some saw dust from sanding to smooth and shape the 1/8" planks

I am certain that if you have any experience building balsawood model airplanes you can do a much better job than this and this does not look too bad. .

The blue between the front and the back is some water resistant fabric purchased at a local fabric store. It attaches by means of neodymium super magnets that are glued and taped to both sides.

These are not the latest pictures of the trike but show it nice and clean looking. It has gotten older and many stickers cover it now.  In the lower right image you can see the repair to the fairing I made but it is not even visible in the other pictures. This is definitely my wet weather vehicle of choice as I am a car free individual.

 

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