Korg-DW8000 CR2032 paperclip battery holder

prusaprinters

<p>This is a replacement battery holder for the 3V battery inside the Korg DW8000 synthesizer keyboard. This battery holder allows for easier swaps of common CR2032 3V lithium coin batteries. It requires a small paperclip cut into two lengths to act as the pins and pressure contacts of the battery holder.</p> <p>The OpenSCAD source files are found here: <a href="https://github.com/bmarr/CR2032-TABBED-HOR-3POS-replacement-holder">https://github.com/bmarr/CR2032-TABBED-HOR-3POS-replacement-holder</a></p> <p>The battery keeps the sound patches in memory, but without this backup current, the RAM loses the sound patches and the keyboard is generally unusable by itself, except as a MIDI keyboard.</p> <p>The original factory-installed battery lasted about 10 years if the keyboard was rarely used. The original battery was directly soldered into the main PCB and requires skilled de-soldering and soldering to remove and replace.</p> <p>The unique battery holder shape avoids interference with nearby components on the board that would otherwise prevent off-the-shelf battery holders from being installed in the original battery location; because this design uses the existing holes for the battery terminals, it avoids the need for other electrical modifications to relocate existing components elsewhere.</p> <p>Skilled de-soldering and re-soldering is still required for this battery holder, but if done correctly it should only have to be done this once! Use clippers to remove the original battery from the circuit board, then use solder cleanup techniques to remove the pins left behind and remove any excess solder. A copper wick desoldering technique works well, and a 0.7mm paperclip can be used as a sort of pipe-cleaner to prepare the through holes (3 of them) for the paperclip-pins that will be used as the battery contacts.</p> <p>Note: A paperclip with a wire diameter of about 0.7mm to 0.8mm is used with this battery holder as the battery contacts. The three battery holes on the PCB accept pins with about 0.8mm diameter. The paperclip is cut into two lengths which are then bent to fit within the channels of the battery holder to make the + and - contacts with the battery and act as the pins through the PCB. The + length of paperclip also acts as a retainer for the coin battery.</p> <p>!!! Solder the paperclips to the PCB without the holder in place, as the plastic will melt !!!</p> <h3>Print Settings</h3> <p><strong>Printer:</strong></p> <p>DuetLEGO (homebrew)</p> <p class="detail-setting rafts"><strong>Rafts: </strong> <div><p>No</p></div> <p><strong>Supports:</strong></p> <p>No</p> <p class="detail-setting resolution"><strong>Resolution: </strong> <div><p>0.2</p></div> <p><strong>Infill:</strong></p> <p>100</p> <p><strong>Filament:</strong></p> Spool3D PETG <p>White</p> <p><br/> <p class="detail-setting notes"><strong>Notes: </strong></p> </p><div><p>Use PETG or other similarly flexible material, as this design relies on the springiness of the material to allow the coin battery to snap into place and stay retained in the holder. PETG will also be better suited to withstand the temperatures of a Korg keyboard left in a hot vehicle parked in the sun - but don't do that to any instrument anyway!</p> Print with a largish brim for best adhesion to the bed. I had to trim it off later with a knife. I used a glass bed cleaned with Simple-Green degreaser soap and then rinsed with distilled water wiped with a paper towel. The bed was heated to 70 C. <p>PrusaSlicer was used to generate the gcode from the STL produced by OpenSCAD.</p> <h3>Post-Printing</h3> <p><strong>Positive contact retaining clip positioned (with holder and battery as guide) and soldered.</strong></p> <p><strong>Battery holder installed.</strong></p> <p><strong>Battery installed and verified as supplying 3V to the memory chips.</strong></p> <h3>How I Designed This</h3> <p><strong>OpenSCAD parametric approach</strong></p> <p>The trickiest parts were getting the paperclip contacts bent just right for enough contact pressure, and ensuring the two retaining tabs for the battery body had strength and flexibility.</p> <p>I have the OpenSCAD source files currently private on github and will make a release soon and update here.</p> <p><strong>Original factory-installed battery.</strong></p> <p><strong>Original battery removed, holes cleaned up and ready for paperclip contacts.</strong></p> </div></p></p> Category: Music