Hotbed for Microcube

thingiverse

Add a heated bed to your microcube for improved PLA bed thickness and the ability to print PETG, ABS, or more. This requires significant power. **Caution:** A heating bed demands substantial power. Verify that your power supply is robust enough. The printer alone necessitates at least 60W (70W for safety), plus the wattage of the heating patch you will use, with an additional safety margin to ensure it. I utilize a 120W power supply for a 40W heating patch. This is particularly crucial if using a cheap Chinese power supply lacking a security cutoff, which often occurs at this price point. **Needed:** - An aluminum plate, 150x150mm in size, with a thickness of 1.5-2mm (less than this may bend and result in an uneven bed; more will work but slow down heating speed). This costs approximately 4€. - A **12V** heating film that fits your aluminum plate. I use a [this one](https://www.reprap-france.com/produit/1234568341-patch-chauffant-polyimide-12v-40w) (100mm, circle, 40W), but search "polyimide heater" on eBay and its counterparts. - A silicon heater patch is also a good choice (but more expensive). - The wattage of the patch directly affects heating speed and maximum temperature. Higher values are beneficial, **but ensure your power supply can handle it**. Excessive power is unnecessary for this printer size (I believe above 50/60W is useless; below 20/25W will be challenging to use). - A standard [100k NTC thermistor](https://www.banggood.com/fr/NTC-Thermistor-100K-With-1M-Cable-For-3D-Printer-RepRap-p-944238.html?rmmds=search) - Kapton/polyimide adhesive for fixing the thermistor and insulation material - Optional: a 150x150mm glass or mirror for better adhesion and flatness. - Optional: insulation material and/or cork sheet. **Instructions:** - Drill four M3/4 holes at the corners of your aluminum plate, centered at 5mm for each side (like you did with your original bed plate). - If using a glass/mirror, countersink the holes on top of the plate to use countersunk screws. - Fix the heating patch on the bottom of the aluminum plate, centered. Ensure all wires are on the same side as the RAMPS of the microcube. - Place the thermistor in the center of the patch and fix it with a large piece of Kapton. The wire should be directed towards the heated patch wires. - Fix the wires to the plate using Kapton. - If using insulation material, cut it to the size of the aluminum plate and secure it with Kapton. Use cotton/heat-resistant material first, then cork. - Add screws and springs to each corner and fix your bed to the microcube platform. - Connect the patch wire to the RAMPS heated bed output (D8, near the main power in). - Connect the thermistor wire to the appropriate NTC sensor (next to the hotend thermistor). - Configure your firmware to enable the heated bed. This setup can easily support a 120°C maximum temperature if your patch can reach it. **Insulation:** It is not necessary, but will improve heating speed and maximum temperature. For reference, here are my measurements with this setup (2mm thickness aluminum plate, 40W 100mm diameter polyimide heating patch): *Without insulation:* - Ambient (25°C) to 60°C in 4 minutes - Maximum temperature: 80°C *With insulation* (2mm insulating cotton + 2mm cork): - Ambient (25°C) to 60°C in 3 minutes - Maximum temperature: 95°C