Rotatable map board for mountain bike orienteering.
The board is easy to detach from the support for travelling.
Can be made at any height depending upon eyesight and preference.
Very easy to make at almost zero cost using commonly available materials and tools.
Step 1: What You Need
2 pieces of 75mm diameter PVC drain pipe, approx 11cm long for the upright and 13cm for the board support. The length of the upright pipe can be varied according to taste, anything from 5 to 15cm will work.
Correx board, I use a 30cm square board but some people prefer smaller sizes.
Hot air gun (paint stripper) for softening the PVC pipe.
Cable ties, various sizes. The cable ties which hold the upright to the bars are the most likely to break in a crash so use the thickest you can find and carry spares with you in case.
Step 2: Make the Upright Support
Soften one end of the shorter piece of pipe with the hot air gun. Continually rotate the pipe to make sure the whole circumference softens evenly. When soft enough press the end of the pipe onto your bike stem. Angle it so that the map will be roughly at right angles to your line of sight when riding. Hold the pipe in place until it has cooled enough to hold it's shape.
Drill 6 holes in the pipe for the fixing cable ties, 2 above each of the mouldings.
Step 3: Mould the Map Board End of the Supporting Pipe
Make multiple 5mm cuts down the end of the support pipe every cm or so.
Use the hot air gun to soften the end and splay it out slightly. This has to be just enough to stop the map board coming off but not too much or you won't be able to get the board on and off easily.
Step 4: Make the Map Support
Take the 13cm long pipe and cut 8 slots down the pipe leaving 3cm uncut at one end.
2 cuts are about 1cm apart. The other 6 are spread equally around the remaining circumference.
Use the hot air gun to soften the pipe at the end of the cuts only. When soft splay out the pipe by pressing it against a flat surface. Hold until cool.
Cut off the 1cm wide flange and then cut through the remaining pipe to split it so that it will go around the supporting pipe made earlier.
Step 5: Put It All Together
Attach the supporting pipe to the bike using 3 cable ties. Use the thickest ties that you can get.
Fit the map support and fix it with a cable tie. Tighten it enough to stop it coming off but not too much to stop it rotating.
Attach the map board to the support using 4 small cable ties. Make the holes in the board using a small screw driver. The unused pipe flanges can be cut off if desired.
Step 6: Attach the Map
The easiest way to attach the map is with bulldog clips. A more sophisticated way is to use clear flexible plastic sheet and adhesive velcro strips.