# Can you sand a pro-mini to make it's holes castellated **URL:** \ **Category:** General Guidance\ **Created:** [January 30, 2023, 9:44am UTC](https://forum.arduino.cc/t/can-you-sand-a-pro-mini-to-make-its-holes-castellated/1084056 "2023-01-30T09:44:25Z")\ **Posts on this page:** 1\ **Showing post:** 11
**Author:** ![LarryD](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/larryd/32/215550_2.png) [@LarryD](https://forum.arduino.cc/u/LarryD)\ **Post date:** [January 30, 2023, 6:30pm UTC](https://forum.arduino.cc/t/can-you-sand-a-pro-mini-to-make-its-holes-castellated/1084056/11 "2023-01-30T18:30:48Z")
See these posts. > [@Share tips you have come across](https://forum.arduino.cc/t/share-tips-you-have-come-across/428745/713): > > If you purchase a board like a Buck Converter 'and' the board doesn't have components on one side, you can use it as a Castellated daughter card on a PCB you design. Use a table sander to take off the edge(s) of the PCB where the through solder holes are located. For insulation/isolation purposes, place Kapton tape on the flat underside of this PCB. When 1/2 of the buck converter hole is removed, solder the remaining plated through hole to the motherboard's pads. On a none castellated edge, … ![image](https://europe1.discourse-cdn.com/arduino/original/4X/d/9/9/d99fe4c8b4987499338326d528cb238ad74a4453.jpeg) * * * > [@Share tips you have come across](https://forum.arduino.cc/t/share-tips-you-have-come-across/428745/1069): > > Hand Soldering Castellated Components It can be difficult to solder castellated components as the area to the left and right of the cove is, usually, glass epoxy. If you follow the images below, you should achieve good results when hand soldering these devices. ![image](https://europe1.discourse-cdn.com/arduino/original/4X/f/f/5/ff520b6488766f3026000b4e431351723c2ee1be.jpeg) --- _[View the full topic](https://forum.arduino.cc/t/can-you-sand-a-pro-mini-to-make-its-holes-castellated/1084056)._