How to make a shapely tailbox in the quick and dirty way that coroplast was meant to be!

This tailbox was made with 4mm coroplast. There are a plethora of thicknesses and colors that could have been used. I think that 2 or 3 mm would be a good candidate for a lot of applications. You can get this stuff in a green house version that has great ultra violet protection. My list of fastening and forming methods are:

• hot melt glue, use the hot variety not the low temp. Use generously like a benevolent philanthropist tycoon.
• wire ties, I call them zip ties.
• duct tape
• sharp pocket knife for cutting
• soldering iron for holes
• treat coroplast like cardboard: Cut, score, fold, whatever!
• The bungees (rubber shock cords) are about 3.5 mm diameter.
• Sharpee marking pens wash off with denatured alcohol.

Figure 1.

1. Cut seat bulkhead to match shape of seat back. My seat back is a Lightening Cycle Dynamics and matches my shoulders well.
2. Cut the head bulkhead so that it is long enough to overlap the seat back by 6" and is slightly smaller than your helmet top.
3. Fold coroplast so that the grain goes front to rear and so that there is enough length to meet the bottom of the seat and to give you the length you want. Make sure that it is extra tall since it will lose some length in the folding. The fold is at the trailing edge.
4. cut seat angle into sides.
5. Braze seat bulkhead to sides an inch behind leading edge. Don't wrap corners yet
6. Braze head bulkhead to seat bulkhead so that it matches your head and shoulders.
7. Braze sides into corners of seat bulkhead and sides of head bulkhead. don't forget tacking zip ties. Use them to pull corners in.
8. test fit sides where they meet at the top from the head bulkhead back. Trim the sides to fit together.
9. Braze the sides together working from the back forward. Use duct tape to hold the sides together along top and tack to the bulkhead with two zip ties.
10. Cut to fit a floor for the glove box.
11. Braze the glove box floor in.
12. Cut the top of the tail box off as shown in figure 2.
13. Add locating strips on the inside of the box so that the top stays on the bottom.
14. Mount the bottom of the tailbox on the back of the seat so that when the upper section is installed it matches your head and shoulders.
15. Your tailbox will need some kind of support structure like a luggage rack or frame member if you intend to load the box with anything (maybe even if you don't load it.)
16. measure and cut the trunk floor with folding lips so that there is some large surface area to braze to. Locate trunk floor to be supported by rack or frame member.
17. Braze trunk floor. Use three or four zip tie tacks.
18. Cut another triangle without lips as a doubler to add extra strength to the trunk floor. Braze in to bottom of floor.
19. Make tongue and bungee hold downs. Two on sides and one in front. Tie off extra bungee inside box. See figue 2.
20. Cut bottom edge of sides to your liking. Consider rear wheel access.

figure 2.

It was my intention to spend time on this webpage in relative proportion to the time I spent building the thing it is about. I probably spent about half the time on this page that I spent on my tailbox.