MARS Recumbent bicycle projects

Zotefoam Manual - Tail
A project by John Tetz - April 2005

Introduction   Mold   Layout   Form   Cut   Glue   Internal Braces   Install the Trike   Tail   Door   Canopy   Turtledeck

Heat form the sides of the tail and trim the S-curve and bottom green/grey line, using the trim system on the mold. Leave about 1” along the top edge. The final trimming will be done on the vehicle. I carved a wheel fairing from mold foam to aid in hand-shaping the Zote:
Rear wheel fairing mold
Rear fairing Zote foam molded to the foam mold
Here is the left side, with the grey bottom color and a black HD 80 wheel fairing. The grey and black pieces were heat-formed separately with a hot air gun and held in place with gloved hands until cooled, then trimmed and glued to the main tail side. Heat-forming the tight compound curves at the leading edge of the black wheel fairing has to be done in a few steps to get the proper shapes. Leave enough material on the leading edge to join with the right side after the two halves are on the vehicle. They will be glued together.

I used a lap joint between the grey and the black because of the differences in thickness and because the HD 80 doesn’t glue very well; the lap joint helps prevent detachment.
Plug in the small U-stiffeners into the bigger U-stiffeners on the shell. I use about 3”. The plug-in sections for the upper ones are shorter, so that when installing the tail, the lower ones are inserted first, then the upper ones. The bottom of the smaller U-stiffener has to be trimmed off to fit into the bigger U-stiffener, but make sure to put a new bottom inside this short plug-in section. Then masking tape each side of the tail to the shell, using the green/grey line as an alignment guide.

Next, mark the location of the smaller U-stiffeners and glue in. The stiffener straddling the green/grey color line extends to the end of the tail. I shortened the upper U-stiffeners on the tail because long ones would interfere with the panniers. These could be around 10” long.

Time to make the tongue & groove alignment joints between the U-stiffeners. Refer to the end of the 6. Internal Braces section for a detailed description if needed. The tail has the groove, while the shell has the tongue. This system does a wonderful job of stabilizing the edges.

When the U-stiffeners and the tongue & groove braces are installed, and the tail is securely taped to the shell (or the over center clips are installed), the rest of the tongue & groove braces for the shell/tail joint can be completed.

This is the time to trim the top edge to fit the line of the shell. Then the top edge tongue & groove braces along the 27.5” line can be constructed.

The shell has the grooves and the turtledeck has the tongues. This system guides the turtledeck onto the shell/tail and provides edge stiffness. The braces extend from the end of the canopy to the end of the tail, with a groove break at the shell/tail joint, but continuous for the tongue on the turtledeck side.

I made six small aluminum over center clips to hold the tail to the shell: one for each of the four U-stiffeners, and one for each of the shell/tail tongue & groove joints. Also, two to hold the turtledeck in place, one for the front edge of the canopy, and one for the canopy to door.
Here are three clips per side holding the tail in place:
Here are the two halves of the tail joined by an end:
This shows the luggage rack end support, which will be glued to the tail and bolted to the luggage rack. Do not glue this in until after the vehicle has been tested and checked out on the road, as you might have to adjust the shell height.
Here is an upside down view of the construction of that support:

Next: Door

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