RETROADSTER, a quad tandem

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Another video about my tandem can be seen here:
http://www.youtube.com/watch?v=CmsbJ5JU8X8
This time I want to show the speed capability of both the tandem and the drivers.
To be fair, the last part shows an uphill climb, steep and painful.

But the way most painful job was the upload of this video with my "Pampa"-DSL.
It takes 45 minutes to upload this 3min-movie, aaarrrghhh.

Kai
 
A further step after the recent plywood frame is a monocoque body, also made from plywood.
Here is my first try with 3D CAD, don't laugh.
fantomsketch2.jpg

And the link to my blog:
http://plycar.blogspot.de/2013/11/the-m ... d-cad.html
I have bought 5 sheets of marine grade gaboon ply, 8x4ft and 4mm thickness.
The shape of the body has to be refined, but SketchUp has not the necessary tools.
I want to use Catia or Solid Works.

Kai
 
That's really cool, I'm ready to see some building on that body.
 
iam also planing a wooden velomobile , a 1place Missile style body on 4 wheels .. your desing is sweet! but looks heavy , well ...in the drawing
 
Wood looks heavy, but isn't. With 4mm gaboon plywood I estimate an empty weight of 120 pounds for the tandem.
Means 60 pounds of weight for each driver, not that much more compared to a cruiser bike.

Kai
 
Over the Easter weekend I began to work on a new stylish tail for the steel tandem.
It's made from birch plywood.
This is todays progress:
houBDChi8jmmGcD6jc2dV9C7oRndB5q35tGfFLuV3lU=w945-h709-no

DSCF1099.JPG

DSCF1101.JPG

The edges will be painted in green, to hide the many screwheads.
The rest of the panels will be painted clear, for a nice wood finish
When the tail is complete, I will build a front hood and maybe doors.

Kai
 
The tail is ready build, although some refinements and minor changes are still to be done.
I have found the perfect rear lights for the Retroadster, in the style of the 30's, but with LEDs.
DSCF1109.JPG

We have made a short trip to the Netherlands, to meet Olaf, a friend with the almost the same interests.
He has made a quadracycle, several velomobiles, cargobikes and also a lawn mower bike just for fun.
It was also fun to cycle a small tour with all these weird bikes.
Here are some photos of our "Odd-Cycles-Tour"
DSCF1153.JPG

DSCF1161.JPG

DSCF1167.JPG

DSCF1179z.jpg

The red quadracycle is also an interpretation of the old Mochet Velocar and in some points closer to the original than my build.
 
I'm recently building the front hood.
DSCF1195s25.jpg

Trying to make the front as narrow as possible, to give the front wheels maximum steering clearance.
The height of the hood must also be kept to a minimum.
74cm/29inches height over ground are actually enough for cranks, heels and toes for circulatng without scratching on the street or hood.
I'm still searching for the best form of the nose, which looks retro and not too agressive.
In the picture the nose tip is too much up, have to be pulled downwards.
Hoping to attach the top and front panel today.
 
Very Cool! I like the design you're going for. Do you think it will ride easier with the body (more aerodynamic?)

I've seen a few people make streamline ones here in Minnesota for easier commuting in the snow and cold
 
The body is more for the look and weather protection, maybe it helps a bit in a headwind.
There is a lot of drag, because of the many obstacles for the airstream, the missing floor board/bottom, the outside front wheels, the wide open cockpit and so on.
It looks streamlined rather than it is really.
It's also difficult to build the shell properly around the steel frame.
I want to build a streamlined plywood monocoque with NO internal frame, with a similar shape to the CAD designs I made previously.
Hoping the missing frame will safe a huge amount of the actual overweight too.
Because all body panels are made from 4mm plywood, the shell is very rigid.
I like that.
Most velomobiles with very thin wall thickness from GRP or Carbon are wobbling and rumbling, not what I want to have.
The benefits of wood is the low density, even Carbon Plastic has a density nearly three times higher.
And the strength of wood is much better than many people are thinking.
For the monocoque I will change my material choice from birch to gaboon, which has just 2/3 of the specific density of birch.

Kai
 
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