TB6600/HY-DIV268N-5A Stepper Driver Case with 40mm Fan

thingiverse

I decided to completely overhaul my old MaxNC-15 CNC Mill, stripping the outdated electronics and replacing them with a Raspberry Pi paired with a Protoneer RPi-CNC HAT board connected to several external HY-DIV286N-5A drivers and modern hybrid bipolar stepper motors. When I started this project, I had no idea how much of a "piece of junk" the HY-DIV286N-5A driver board truly is. If you decide to use these drivers, don't expect them to just work - be prepared to completely rework the entire circuit. For some insight on what needs to be done, check out this thread: http://www.cnczone.com/forums/stepper-motors-drives/186930-tb6600-drive-ebay.html The most important changes are to remove the series diode from the incoming power feed so that back EMF can unload into the power supply and add decoupling/filter caps on the Vref line (current limiter reference voltage). Reducing the load on the Vreg (+5V) is also crucial, such as moving the LEDs to be powered from VIN instead of the on-board generated +5V. Also, make sure to check all parts to ensure that they are installed correctly - for example, verify that the resistors on the optoisolators aren't 56-ohm parts. They should be 270-ohm or 330-ohm or even 560-ohm parts as marked on the PCB, but some boards have 56-ohm resistors (stamped as "560" on the resistor) installed instead of their intended 560-ohm resistor (stamped as "561" on the resistor). There are several different variations of these driver boards each with various levels of problems. So, you're at the mercy of luck when it comes to what you'll receive and how much work you'll have to do to fix it. And most all of them have incorrect charts on the case for the microstep and current limit dip-switch settings - they didn't even get that right! While modifying my driver boards, I decided to add an "alert" LED to show when the driver chip is hitting either the current limiter or the thermal limiter and add a cooling fan to allow running at higher currents without overheating. To do this, I needed a better case with additional LED holes and a mounting hole for a 40mm fan. I found this design on Thingiverse, but it didn't have holes for the screws to hold it in place on the heatsink and wasn't very customizable for different LED configurations, so I decided to create one from scratch using OpenSCAD. Note that this OpenSCAD file requires the current development snapshot of OpenSCAD or you'll need to comment out and/or delete the 'assert' statements in the code. Those are only used to ensure consistency and are not necessary for rendering the model. I also pulled in the 40mm Fan Grill from the Sanginololo case and copied it here to make it easier to find. Those little 40mm fan grills print really nice and work well, but there's nothing in my OpenSCAD code for them. I have included STL files rendered for both the original 2-LED configuration and the 3-LED configuration I used. To recreate the STL files with a taller box, just add a couple millimetres to the "BoxHeight" variable where it's being computed from the original box height and the change in wall thickness between this case and the original case. My next task is to completely redesign this driver module in case I need replacements for these. That will be much easier than having to modify additional boards in the future. If I do redesign it, I'll probably do a board turn on OSHPark and make it available there. Update (2016-12-11): I finally completed redesigning the TB6600 driver. The new design is a much improved drop-in replacement for the HY-DIV268N module, allowing you to use your existing heatsink and configuration. The design files can be found at https://github.com/dewhisna/TB6600StepperDriver and boards can be ordered from https://www.oshpark.com/shared_projects/tKN4X7AL. Print Settings: Printer: FlashForge Creator Pro Rafts: No Supports: Yes Resolution: 0.2 Infill: 35%