I’ve never been happy with the various bags and boxes that I’ve used to store tools snd spares on my Trice Monster’s Air-Pro Seat. They always rattled around and looked like an afterthought. A few months ago I had some free time while recuperating from back surgery. So I thought I’d tackle the problem by making a carbon fiber trunk that could be securely mounted to the seat. The goal was to make it just large enough to carry tools and spares and to look like it belonged on the Monster. With the first version, I tried to use the space between the upper seat back and the rear wheel. Below you can see the foam plug which was eventually painted and used to produce the mold. Without showing the mold and the intermediate steps, you can see the final trunk mounted on the Monster.

I wasn’t too happy with this trunk. It looked too bulky and odd shaped on the Monster. It also had the obvious problem of only fitting at one seat angle. I wanted something that fit with multiple seat angles and was less conspicuous. So I came up with this rectangular shaped trunk that fits between the ribs on the lower back of the seat. The plug is shown below. It was made from a combination of a carbon fiber mold taken from the back of the seat and foam that was shaped and painted.The green tape, barely visible on the plug, shows where a door would be cut from the final part.

The two part mold of this plug (not shown) was difficult to make and more difficult to use. It was split along the line formed where the light part meets the dark part of the plug. The final part was built by laying up the two halves, cutting the door out of one half, then bonding the two halves together. Next, the door, with hinges and latch, was mounted. The part required some body work and paint to make it presentable. It’s mounted to the seat with M5 screws using existing holes in the seat. Access to the trunk is a little awkward. The rear seat bolt has to be released and the seat rotated up.

I’m pretty happy with this trunk in spite of the marginal finish. I think that a professionally refined and produced product similar to this could be a decent seller considering how many ICE trikes are equipped with this seat. Perhaps a similar part could be made more easily and cheaply in ABS plastic using a vacuum forming process instead of hand layup carbon fiber. I leave that to the professionals.