I just ordered the Jackpot controller for my laser engraver build, so it will be along soon I’m sure. That said has anyone implemented optical limit switches with the Jackpot controller? I’ve searched the forum but couldn’t seem to find anything.
Thanks!
There really should be no difference other than you need to add some of the power pins to the header I left empty.
Anecdotally, I have an optical sensor on one of my 3D printer Z axis’s and I find it is less accurate than a cheapo microswitch that my other printers have.
Thanks for the feedback!
The cheap microswitches are very accurate, but I was always happy with the optical switches. they’re a little sensitive to dust and debris, but then so are the microswitches. It’s never been a problem on my printers before, when I did sometimes have printers try to hammer the microswitches off of their mounts, the optical ones have no physical contact, and so they lasted longer on my printers. I generally use them when I can, though the MP3DP v4 would be difficult to adapt, presumably the v5 will as well.
Easy to set up on the Jackpot though, I did just for the heck of it to test. I also did on the Bart Dring 2209 board, but that required more finagling to split the 5V pin available to 2 sensors, though that wasn’t so big a deal. I may make a breadboard add-on to put the JST-XH connectors on that the optical stops want though. One 5V to the 5V pin, and 2 Ground/Pin sets to the extant 2 pin ground connectors.
Am using regular micro switches. But if you’re looking to do something different, consider hall effect sensors, more effort to setup. Steve Potter uses and seems to like them. Steve’s setup was built before Jackpot existed.
Well, considering that a BLTouch is basically a Hall effect sensor switch, we have adequate proof of them being accurate and repeatable.
I suppose that we could do something like a piezo sensor as well. I tried this with 3D printing, but was never able to get it to be as accurate as I wanted, but then I was also dealing with lots of Chinese parts put together in ways they weren’t really intended to be, so I never got the kind of sensor mounts that would produce the best results.
I don’t think there’s any good reason to stray too far from the beaten path here. The switching technology that we have for CNC use is accurate enough, unless we go to something really esoteric and consequently expensive. This goes against the core philosophy that I get from the V1 designs of being obtainable, buildable and repairable.
I really do like Hall effect switches (not to be confused with a Hall (analog) sensor). Immune to any kind of dust, and unlike the more expensive (by a factor of >10) proximity sensors, will never trigger off your belt buckle or random piece of metal. It has to be a magnet within 5mm, specifically, the south pole.
I did repeatability testing using a precision caliper and found the repeatability of when it triggers is about 15 microns, vs 10 microns for the mechanical microswitch, so not quite as accurate (0.2 mils or thou worse, for you Americans). Will not break or suffer from vibration. Adding a pull-up resistor and filter capacitor to the cable is just a bit of soldering, nothing tricky.
