5 ‐ Base Assembly - chrisjameschamp/DIY-Active-Pedal-Design GitHub Wiki
Assembly
The base assembly consists of three main parts: the Base Front, Base Rear, and PCB Cover.
To get started, you'll need a soldering iron — ideally one with a tip designed for heat set inserts like the one shown above. You can purchase a compatible iron here, and the M3 heat set insert tip here. The M3 tip will work for all inserts used in this project.
Required inserts:
- 2 × M3 Heat Set Inserts
- 2 × M4 Heat Set Inserts
- 1 × M5 Heat Set Insert
On the Base Rear:
- Insert 2 M3 inserts (circled in pink)
- Insert 2 M4 inserts (yellow)
- Insert 1 M5 insert (green)
- Do not insert anything into the red-circled holes — they will be used later
Tips for Using Plastic Heat Inserts
Place the insert on your iron tip and gently press it into the hole. The heat will soften the plastic, allowing the insert to sink in. Apply steady, even pressure to keep it straight.
With nylon, inserts sometimes try to back out when the iron is removed. To avoid this:
- Use tweezers or pliers to apply pressure while the insert cools
After insertion, you’ll often see excess plastic “mushrooming” around the insert.
Use a razor blade to trim it flush. If your blade catches on the insert, it's not seated far enough — reheat and push slightly deeper.
Attaching the PCB Cover
Align the PCB Cover into its cutout on the Base Rear. It may require gentle tapping with a hammer, especially if printed in nylon.
If you're using other materials, be cautious with impact force.
Install the following:
Flip the assembly over — it should look like this:
Marrying the Base Front and Base Rear
Grab both the Base Rear (with PCB Cover) and Base Front.
Use:
- 2 × M5x18mm Socket Cap Screws
- 2 × M5 Hex Nuts
Warning: Some CAD files show nylon lock nuts. These create too much friction and can damage the part — use regular nuts only.
Insert screws from the Base Rear side. Seat the nuts in the Base Front, using a wrench if needed.
Once the nut is seated properly, you should be able to tighten the screw without a wrench. Alternate tightening each side evenly for a flush fit.
More Heat Set Inserts
Install:
- 12 × M4 Heat Set Inserts around the edge of the base
- Leave the 4 central holes empty for now
Then add:
- 3 × M3 Heat Set Inserts into the three holes on the back of the Base Rear
Prepping the PCBs
This build uses the excellent open-source PCB designs by gilphilbert, specifically the:
- V1.2 Control Board
- V1.1 Power Board
You can order both boards pre-assembled from JLCPCB, but a few components must still be soldered manually.
Before proceeding, we need to configure the DIP switches to identify which type of pedal you're building: Throttle, Brake, or Clutch.
Locate the DIP switch circled in pink in the image below:
There’s a guide printed on the back of the PCB itself, but for quick reference, here’s a clearer version:
Set the switches according to the chart to match your desired pedal type.
From the Servo Motor & Rail Assembly guide, you’ll already have used some parts from this JST-XH Connector Kit. For this step, you’ll need:
- 3 × 2-pin headers
- 1 × 3-pin header
- 1 × 4-pin header
- 1 × 5-pin header
All of these are included in the kit above.
Next, grab the Control PCB, a 12" (30cm) coax cable, 3 × M3x6mm Cap Head Screws, and some Kapton tape.
Apply Kapton tape to the underside of the control board, fully covering any exposed pins or traces.
This is a safety precaution: although rare, carbon fiber-filled filaments could potentially cause electrical shorts if traces come into contact with the printed surface.
Repeat this step for the Power PCB. You can set the Power PCB aside for now — we’ll return to it shortly.
Tip: If the tape covers any mounting holes, you can gently score it with a razor blade to allow screws to pass through cleanly.
Electronics Assembly
Insert the Control PCB into the center cavity of the Base Rear, with the Kapton-insulated side facing down.
Secure the board using 3 × M3x6mm Cap Head Screws.
Feed the coax cable through both side openings in the base. The smaller end should go in first — the larger SMA connector won't fit through the holes.
The picture only shows it routed through the left side opening, make sure to route it through both openings.
Connect the small end of the coax cable to the antenna port on the Control PCB.
Place the servo motor and linear rail assembly with the PCB housing facing up.
Then place the base assembly over it — the servo wires should pass through the front-side opening. The base should sit flush over the motor housing.
The base assembly will just rest on the servo and linear rail for now but will be attached together in a later step.
Identify the two thickest-gauge wires — these are your power leads. Measure them from their origin point to the last cavity opening and trim them to length.
Strip about 10mm (~½") of insulation, twist the strands, and tin the ends with solder. Then add heat shrink tubing, leaving ~2–3mm of exposed tip.
Route both wires through the first and second openings in the base.
Attach them to the screw terminal block on the Power PCB — red to V+, black to V-. Take care not to overtighten the screws, as this can damage the terminal solder joints.
Secure the Power PCB into the rear cavity using 3 × M3x6mm Cap Head Screws.
Grab a 6-pin FFC Converter Board and a 6-pin ribbon cable.
Trim the ribbon cable to length — it should reach comfortably from the Power PCB cavity to the Control PCB cavity.
Use a 5-pin JST-XH female connector and crimp terminals. For best results, use the iCrimp IWS-3220M tool.
Crimp and insert the wires in the following order (left to right):
- Red
- Black
- Yellow
- Blue
- Green
Double-check orientation: Red must align with the 5V pin on the Control PCB header.
Strip and tin the other ends of the wires (~2–3mm), then solder them to the top side of the converter board in this order:
- Pin 1 → Red
- Pin 2 → Black
- Pin 3 → Yellow
- Pin 4 → Blue
- Pin 5 → Green
Solder from the same side as the ribbon cable connector to avoid excess buildup on the underside.
Cover the bottom side of the board with Kapton tape for insulation. Again, score mounting holes if necessary.
Take the 300mm FFC Ribbon Cable. With the connector lock open, insert the cable fully — exposed side should face the contacts.
Once the ribbon cable is fully inserted into the connector, close the lock to secure it.
In the base assembly, there's a slot in the corner of the cavity where you placed the power PCB.
Feed the ribbon cable through this slot so that it exits cleanly into the adjacent compartment.
Gently move the power and ground servo motor wires aside, and place the ribbon cable PCB into position.
Use the cutout in the base assembly as a guide and visually confirm alignment with the mounting holes before securing.
Attach the board using 2 × M3x6mm Cap Head Screws.
Carefully feed the attached JST connector through the cable opening into the control PCB cavity.
Adjust the cable so there’s even slack between both cavities, then plug it into the 5-pin JST header on the control PCB.
Trim the 3-wire ribbon cable (TX/GND/RX) from the servo motor to the correct length, as shown.
Crimp on a 3-pin JST-XH connector.
Important: The pin order differs between the servo motor and the control PCB.
- On the servo motor PCB:
TX,GND,RX - On the control PCB:
TX,RX,GND
Be sure to match each signal accordingly, even if the physical positions differ.
Now trim and prepare the 4-wire ribbon cable from the servo motor (used for direction/pulse signals).
Make sure the wires are inserted into the JST connector in the correct order:
- The purple wire (DIR–) should be in the corner position.
Trim two wires (positive and ground) to the length of one cavity, as pictured:
Crimp JST connectors onto both ends of the wires.
Ensure the orientation is the same on both sides for proper polarity alignment.
Connect the wires between the Control PCB and the Power PCB — this completes the 5V power bridge.
Rear IO Bracket Assembly
Begin by gathering the Rear IO Bracket and Rear Cover. You'll need both for the following steps.
Use a USB-C panel mount extension cable. This guide is designed around this specific USB-C Extension Cable.
The non-panel mount end of this cable is too bulky to fit inside the enclosure, so we need to reduce its size.
Carefully score the outer rubber sleeve with a razor blade, then peel it back to expose the slimmer USB-C connector underneath.
Feed the USB-C extension cable through the slot in the Rear IO Bracket.
Use a 6-Pin PCIe Extension Cable. Each will be cut and wired into the PSU.
- Cut the cable about 75% down the male side, keeping the female end for wiring.
- Save the male ends for use later.
If using braided cables:
- Carefully melt the braid with a lighter.
- Pull the end off with pliers to clean it up.
Then:
- Strip each wire ~20mm (¾").
- Twist the top three wires together (clip side = positive).
- Twist the bottom three wires together (opposite side = negative).
Grab a female XT30 Connector and trim its leads to the same length as one cavity.
Slide a heat shrink tube over each of the positive and negative wires.
Use a hook splice to solder the:
- Top 3 wires to the red XT30 wire
- Bottom 3 wires to the black XT30 wire
Once soldered:
- Slide the heat shrink tubing over the joint
- Shrink it with a lighter or heat gun for a secure and insulated connection
Insert the XT30 connector into the Rear IO Bracket.
Important: Make sure the small locking tab is facing up — this will be upside-down during assembly.
Feed the XT30 power cable through the rear-most opening of the enclosure and plug it into the XT30 header on the Power PCB.
Now feed the USB-C cable through the same rear opening.
It will be a tight fit but will slide through cleanly with a bit of patience.
Slowly push the Rear IO Bracket into the Base Assembly.
There are a lot of wires to manage, so work carefully and go little by little.
The power cable should be flexible enough to loop around inside the enclosure, allowing the bracket to fully seat.
Important: Route the antenna coax cable through the small cutout in the base assembly as you install the bracket. The cable should route downward in the current orientation.
Secure the Rear IO Bracket with 2 × M3x20mm Cap Head Screws.
Take the USB cable and coil it loosely as shown below:
Carefully part the load cell wires and servo power wires.
Slide the USB-C connector through the opening and plug it into the Control PCB.
After plugging it in, coil the USB cable neatly and tuck it between the capacitors on the Power PCB.
Attaching the Base Plate
If you are using a machined base plate, skip this first step.
If you are using a 3D printed base plate, you need to insert:
- 4 × M5 Standard Nuts into the hex cutouts in the base assembly.
For machined base plates:
- Tap the four holes marked with green arrows below using an M5x0.8 thread tap.
- The recommended material (6061 aluminum) should tap easily.
Place the base plate onto the Base Assembly, aligning the pre-drilled holes.
Make sure the countersinks are facing upward.
Install:
Tighten them in a clockwise pattern, starting at the center and working outward.
Optional: Vibration Isolation
This next step is optional, but highly recommended. To help isolate vibrations from the pedals and prevent them from transferring into your sim rig, you can add a thin layer of adhesive silicone underneath the assembly.
Cut a strip of silicone to approximately 15¾ inches × 2¼ inches (400mm × 57mm).
Apply it centered along the bottom of the base plate:
Note:
It's okay if the silicone covers the center mounting screws.
However, do not cover the screw heads for the base plate perimeter — you'll need access to these screws for future maintenance or troubleshooting.
Carefully flip the assembly over.
Important: The linear rail and servo motor are not yet secured, and you must also avoid crushing the hanging ribbon cable.
Depending on your base plate:
| Base Plate Type | Screw Size | Notes |
|---|---|---|
| Machined Plate | M5x35mm Cap Head Screws | |
| 3D Printed Plate (with nuts) | M5x30mm Cap Head Screws |
You will also need:
- 8 × M5 Undersized Washers (2 washers per screw)
The washers ensure the screws tighten to the correct depth without damaging the part.
Insert:
- 1 × Screw + 2 Washers into each linear rail mounting hole
- Tighten firmly, but do not over-torque.
Attaching the Rear Cover
Now we can install the Rear Cover onto the back of the Base Assembly.
You will need:
First, insert the two M3 Heat Set Inserts into the yellow-circled holes on the Rear IO Bracket.
Next, slot the Rear Cover over the PCIe connector and position it so that it sandwiches the USB connector between the Rear IO Bracket and the Rear Cover.
Secure the Rear Cover using:
- 2 × M3x16mm Cap Head Screws (top screw positions — into the new heat set inserts)
- 1 × M3x30mm Cap Head Screw (bottom center position)
✅ Congratulations!
You’ve successfully completed the full Base Assembly — this is the most complex part of the build. From here, it’s all downhill!