The DRE20 V2 converts the BOSS - RE-20 Space Echo Twin Pedal into an Eurorack module. The DRE20 V2.0 contains 1 voltage controlled switch which control the Tap (tempo) button. The set includes an adjustable DC-DC step down converter. The CV control of the Expression pedal is not implemented yet.
While all required screws can be re-used from the Boss Re-20, following additional parts are required:
7 pcs. 3.5 mm Eurorack Jacks PJ301CM Stereo https://www.thonk.co.uk/shop/3-5mm-jacks/
Wire to connect the jacks with the PCB https://www.rapidonline.com/catalogue/search?Query=Wire%207%2F0.2
Disassemble the Boss RE-20 Space Echo and remove carefully the glued metal sticker in the center of the device. Disconnect the two ribbon cables of the PCBs since the front PCB needs to be trimmed that it fits into the Eurorack.
Cut small strips with the hand saw from the RE-20 front PCB (the PCB which contains the potentiometers and LEDs) from the top and the bottom that it fits later into the Eurorack. See below photo showing one of the cut parts.
Unsolder all jacks and solder cables to connect the Eurorack jacks to the PCB. Solder the Eurojacks to the cables and screw the spacers with existing screws from the Boss RE-20 onto the back of the front PCB.
Screw the Boss RE-20 aluminium panel with the 3D printed front panel with two of the Boss RE-20 aluminium panel screws together. Widen the holes for the screw on the top of the aluminium panels with a drilling machine (or similar) until the two holes of the aluminium panel align with the threads of the Eurorack.
Align the 3D printed buttons on the 2 switches of the RE-20 PCB and screw PCB with 4 of the existing screws (from the Boss RE-20) on the back of the 3D printed front panel
Align the cables between the two PCBs, connect the two ribbon cables and screw the PCB onto the spacers between.
For the power supply, either the original power supply can be used or the included power converter which converts the 12V of the Eurorack into the required 9V for the Boss RE-20.
Download the STL files and print your own Mounting Kit
The DRE20 Boss RE-20 Space Echo Eurorack STL files on Thingiverse: https://www.thingiverse.com/thing:3268656
Demo on Youtube