Bicycle Map Holder

Here is my bike map holder project.
I tried to make it both inexpensive and well-made (durable).

1. Handlebar extender (20 cm): https://aliexpress.com/item/1005007426713255.html
2. Map holder board: HDF board, 6 mm waterproof plywood, plexiglass or PET-G sheet.
3. M6x140 bolt (or longer) with a flat cylindrical head
4. 6x M6 self-locking nuts
5. Old bicycle inner tube
6. 19 mm (¾ inch) binder clips
7. 30x40 cm (or 31x43 cm) zip-lock bags for rainy days
8. Silicone adapters (for narrower handlebars): https://pl.aliexpress.com/item/1005006979879069.html

Before we start building the map holder, one thing:
My friend's daughter — with whom I've ridden hundreds of kilometers — is battling cancer and needs help.

Please consider offering your support: https://www.siepomaga.pl/en/waleczna-agata

The first step is cutting out the 30x30 cm board for the map holder from HDF board.

This is a prototype of my map holder, which is why I used HDF board.
In the future, I plan to use plexiglass, as it is resistant to rain.

I drilled holes with a diameter of 6 mm in the board, spaced 18 cm apart.
The holes are located 12 cm from the bottom edge of the board.

The second step is drilling 6 mm diameter holes in the handlebar extension tube.
The holes are spaced 18 cm apart.

To ensure the highest possible accuracy, I bought this drill guide:
https://pl.aliexpress.com/item/1005004989743584.html
(this is where my tendency toward perfectionism comes into play :-) )

Next, I 3D printed a mount for the tube and the purchased drill guide.

The next step is assembling the entire map holder.
To prevent the bolts from loosening, I used self-locking nuts with a polyamide insert.

1. First, I attached the bolts to the map holder board.
Since the bolts didn’t have a full thread, I 3D printed plastic bushings.
If I didn't have a 3D printer, I would probably make this part out of wood.

2. The next step is fastening the nuts that go above (in the drawing, “below”) the extender tube.
These nuts need to be mounted upside down.
To do this, it's best to take another M6 bolt and thread the nuts onto it normally to create a thread in the polyamide insert.
Only then should you screw the nuts onto the map holder bolts (upside down).

3. Finally, insert the extender tube onto the map holder bolts and tighten them.
Remember to install the handlebar extensions on the tube before tightening everything.
Since the tube is made of thin aluminum, I 3D printed side caps to protect it from being excessively crushed.

The second-to-last step is attaching the map holder to the bicycle handlebar.
To avoid scratching the handlebar, I recommend using an old bicycle inner tube.

For narrower handlebars, you can use silicone adapters:
https://pl.aliexpress.com/item/1005006979879069.html

The final step is attaching the map.
To secure the map, I used 19 mm (¾ inch) binder clips.
(I don’t recommend the 15 mm (½ inch) ones, as they don’t have enough clamping force.)

For rainy days, you can use a 30x40 cm (or 31x43 cm) zip-lock bag.

The 3D models used in this project are available in the GitHub repository:
https://github.com/bytezar/3d-models/tree/main/bicycle-map-holder-v01

ReadMe for whole repository:
https://github.com/bytezar/3d-models/blob/main/README.md