I have been planning to build a formula wheel for quite some time. Finally found the time to design and build something. While this is my first custom wheel, I'm happy with how it all turned out. I spend many hours designing and building this wheel but I like to share and give back to the community. I hope you too are able to build this awesome steering wheel and or get inspired to design you own.
I will try to write down a brief how to. In principle this wheel is build using similar techniques as Amstudio - HOW TO MAKE A DIY AUDI DTM STEERING WHEEL, just search YouTube for the video. I will try to keep improving this guide if things are unclear. But I can't explain everything in full detail here I guess, so you might have to look up some things elsewhere.
Cut the base plate
I made the base plate using basic tools, but if you have access to a laser, water or CNC cutter the end result will be even nicer. But its definitely doable using the following basic tools: jig saw, file(s) or rotary tool, drill, etc. The steps below show the process I used to cut the base plate.
- Print the "Formula B1 - Base Drawing.pdf"
- Make sure it's printed at 100% and not scale up or down
- You can check this by measuring the 70mm bolt pattern
- Use a pair of scissors to cut out the outer and inner shape
- Use some glue to glue the design to the aluminium base plate
- Cut out the shape using a jig saw
- Use a file or rotary tool with mill to smooth the edges
- Drill the holes
- Use a bit of sandpaper to finish the edges and holes
Paint or wrap the base plate
I didn't like the look of the plain aluminium, but if you like it you can move to the next step. If you're like me, you have a couple options. You can do what I did and use spray paint to paint the aluminium black (apply some primer and optional clear coat as well). Or you can use (carbon) vinyl wrap for an even quicker result.
3D Print the components
This should be straightforward. Non of the 3D printed components need to be super strong. I printed everything in black PLA with an infill of 30-50%.
Assemble the shifters
To assemble the shifters follow the procedure below:
- Use some super glue to glue the magnets in the lever and body
- Solder two wires to each switch, one to the NO and one to the COM/GND pin
- Mount each switch using two m3 bolts, two nuts and the switch mount
- Push the m4 mounting nuts into the base
- Fix the lever in de body by using the axle
- Mount the shifter paddle to the shifter using two m3 bolts and nuts
Wrap and mount the handle bars
This step is not absolutely necessary but I think the wheel looks and feels much nicer when the handles are wrapped in suede leather. I have not used the wheel yet, but I guess its best to use gloves to keep the suede in good shape. Alternatively you could also wrap the handles in normal leather or sky/fake leather for a bit more durability.
I thought this step would be much harder, but I'm really satisfied with end result. I guess having the right glue is the most important thing. I ordered the exact same glue as Amstudio uses for his wheels: Multibond - contact adhesive shoe fix. Other glues might work fine as well, but this is just the one I can recommend. Furthermore, I sanded the 3D printed handles a little bit to have better adhesion.
For instruction on how to do the actual wrap, the YouTube video's by Amstudio are a good starting point. One important thing to note: put in the nuts (with some glue) BEFORE applying the (suede) leather wrap.
Once you have wrapped the handles, use a utility knife to make the holes in the back of the handles and mount the handles to the base using six m3 bolts.
Wrap the 3D printed enclosure
This step is optional as well. But if you like you can wrap the bottom of the 3D printed enclosure for a nice carbon look.
Make the (coiled) USB cable
Since I was unable to find good quality coiled cable for a reasonable price I made one myself. You can find some tutorials on Youtube on how to do this (you just need a heat gun/hairdryer and optional a drill). The next step is to cut the device connector (so keep the standard A male connector) from the cable, and strip down the wires. Now you can solder the wires of the USB cable to you 4-pin aviation connector (female side). I would recommend to use the following pinout:
- USB VCC -> pin 1 GX12
- USB Data- -> pin 2 GX12
- USB Data+ -> pin 3 GX12
- USB GND -> pin 4 GX12
Mount the Arduino and aviation connector
Depending on where you bought the Arduino screw terminal board you might have to solder the board first. Once this is done follow the steps below:
- Use a file to make the bottom of the Arduino screw terminal board as flat as possible
- Use some material for isolation between the board and the base. I used double sided tape for this.
- Use two m3 bolts and nuts to mount the Arduino screw terminal board to the base (don't forget to add the F3 logo if you like that)
- Press the Arduino Pro Micro into the screw terminal board
- Mount the connector mount to the base using two m4 bolts and nuts
- Cut a micro USB cable to the right length (approximately 5 cm)
- Put the cable through the hole of the connector mount
- Strip the cable and solder the wires to the GX12 aviation connector (male side)
- Use the same pinout as described at
Make the (coiled) USB cable
- Mount the GX12 aviation connector on the connector mount
- Plug the micro USB cable into the Arduino
The first 2 steps are just to prevent the board from making shorts with the base plate. This does not apply when using a carbonfiber base I guess. Moreover, while writing down this guide I figured that you could also use a couple small (plastic) standoffs. This is actually a nicer/easier solution then the one I just proposed.
Mount the buttons and solder the button wires
Mount the buttons to the base plate and don't forget to also mount the four buttons strips. Secure the buttons with the supplied nut, I could not fit the washer (with my 5mm base) but if you can use that as well. Next up is soldering. Below the workflow I used:
- Use a single wire to connect all buttons on the left side and connect this to a single GND on the Arduino
- Solder separate wires to all buttons on the left side (as seen from the front)
- Connect the wires of the top left to bottom left buttons to pins: 2, 3, 4, 5, 6, 7
- Use a single wire to connect all buttons on the right side and connect this to a single GND on the Arduino
- Solder separate wires to all buttons on the right side (as seen from the front)
- Connect the wires of the top right to bottom right buttons: 21, 20, 19, 18, 15, 14
Finally I used two cable clips to make sure all cable stay in the middle and the enclose fits. You can use a couple additional tie-wraps to make the wires look even nicer. Another thing to note, make sure the wires between button 4 and 5 (and 10 and 11) are not too short. I made mine a bit too short at first and they just snapped while mounting the enclosure. This happens because of the shifter reinforcement on the inside of the enclosure box.
Add the threaded inserts to the enclose
Push the four m3 inserts into the enclose. I used a soldering iron to push them in. But perhaps you can also do it without heat. If it does not work I guess you could use a drill to make the holes a bit smaller and glue them in.
Mount the shifters to the enclosure
Use four m4 bolts to mount the shifters to the back of the enclosure box. Put the shifter wires through the little holes of the box. Connect the shifter wires to the following pins on the Arduino:
- Down shift: pin 8 and pin 9
- Up shift: pin 16 and 10
Program the Arduino
hid_joystick_formula_b1.zip archive and extract all files. Next open the
hid_joystick_formula_b1.ino file using the Arduino IDE, select the right board and port and press the upload button.
Final touches, mount to you base and "enjoy the shit out of it"
I guess you could skip this step if you're not using a direct drive base. But I added three metal tube inserts to add some strength. You need to cut three 26mm (8mm outer, 6mm inner diameter) aluminium/steel tube and insert them into the enclose. I used a little bit of super glue to prevent them from falling out.
The wheel has a regular 70mm bold pattern, you should be able to find a suitable adapter for your base (G29, T300, etc.) or just mount it directly (OSW). So mount it and enjoy the shit out of it!
Steering wheel components
NOTE I'm quite sure about all the bolt sizes but I have not disassembled my wheel to measure the bolts again. If you find a mistake could you please let me know so I can update the list.
- Soldering iron
- Hex (allen) keys
- Pair of scissors
- Jig saw with aluminium blade
- Drill 3, 4, 5, 12 mm
- File or rotary tool with mill
- Utility knife