Modified microwave cures resin components in type – Hackaday
Once you’ve made the jump to resin-based 3D printing, you’ll quickly find that curing parts in the sun isn’t always a viable solution. The best way to get consistent results is with a special curing chamber that not only rotates the parts so that they are evenly exposed to light, but also allows you to enter a specific curing time. A beeper that sounds when the part is done would also come in handy. Wait, this sounds kind of familiar …
As you might expect [Stynus] isn’t the first person to notice the similarities between an ideal UV curing machine and the low-profile microwave oven. But his conversion is certainly one of the smartest we have ever seen. The end product looks less like a hacked microwave than a specially designed curing machine, thanks in large part to the fact that all of the original controls are still functional.
The big break there came when [Stynus] noticed the control panel was powered by a one-time programmable PIC16C65B microcontroller. Swapping it out for the pin-compatible PIC16F877A opened up the ability to write custom firmware to interface with all of the microwave’s original hardware. All he had to do was reverse engineer the wiring. It took me some time to figure out how the limited pins on the microcontroller operated the LED display and read the buttons and switches at the same time, but we would say the end result is more than worth the work.
With full control over the hardware of the microwave [Stynus] All that was required was to remove all of the scary high voltage bits (which initially stopped working) and install a number of UV LEDs. Now he can simply throw a part on the plate, turn the dial to the desired curing time and press a button. In the video below you can see that he has even re-used some of the buttons on the control panel so that he can, for example, set a new default cooking time on EEPROM.
Compared to traditional FDM (Fused Deposition Modeling) 3D printers, resin printing requires a lot of additional post-processing and equipment. You don’t necessarily have to gouge your microwave to harden your prints, but you should consider what your workflow will be before you pull the trigger on this shiny new printer.