Hi folks! Just started working on my table - going for a 2x4ft coffee table modeled after the Kevin (khgrap) and Rocketman builds. Big thanks to them and everyone else for the helpful posts, Jeff for Sandify and the world of insight as I read through the forums, and of course to Ryan!
Got most of the parts over the last week, and things came together pretty smoothly with some help from my teenage daughter. I went with the Makerbase3d MKS-DLC32 board with the 2099 stepper chips and the optional TS24 screen (which did help in that I didn’t need to think about getting any PC software going while just getting the motors working and the axes setup). (I went with “Suit 7” from that link, $41.99). They shipped it from China but it only took a week to get to my door.
The screen comes up at first looking like gibberish - I thought I had it connected wrong but the default firmware is for the other screen option, so you have to immediately flash it to the “TS24, Laser, CoreXY machine” firmware and then the screen is happy and it understands CoreXY.
I bought the 3d printed Zenxy V2 parts, bearings, and spinners from V1E. My base is a 1/4" 2ftx4ft MDF board from Home Depot, I tried to find HDF / treated hardboard like Rocketman mentioned but couldn’t find it anywhere in the size I needed. This is working for now and not really sagging but I’m thinking about reinforcing the long edges with a metal angle strip. I also put a cork pad between the stepper motor and mount (and bought some slightly longer screws to fit it in).
Endstops were “sold out” at V1E so I wound up buying the MakerHawk Optical Endstops from Amazon which look identical and fit perfectly into the mounting holes. Big issue with the DLC-32 board that took me too long to figure out - the wires the endstops come with have keyed connectors, that fit both the endstop and the connector on the DLC32 board so they can only insert one way. Unfortunately the pinout is wrong from what the DLC32 wants - the signal and +V lines need to be swapped. Once I figured that out I pulled the pins and swapped the red and white wires and they started working fine.
The 3D-printed Y axis endstop trigger wound up being a bit too short to actually trigger the endstop. I glued a small metal strip (nosepiece from a pandemic mask!) over it to make it a bit longer and that worked fine.
The Zenxy V2 page has some GRBL setup code for homing. The DLC32 firmware with default compile options either auto-homes both axes with $H (but does X-axis first) or allows you to home a single axis but aborts when the alarm triggers because you hit the endstop. D’oh! But it turns out you can disable that by starting with $X to disable alarms, which took me quite a while to figure out. I also didn’t understand the negative moves in the suggested code - it just kept ramming my motors into the stops, and I was happier actually backing them off a bit in the positive direction (plus my table will be large so I’m not worried about losing a bit of space). So my prefix wound up being the following, which seems to be working out fine:
G92 X0 Y0
G1 X2 F2000
I also hit one extremely minor Sandify bug which is that it seems to take the first two lines in the Export field and put them on a single gcode line, which may or may not be valid gcode but my board was ignoring it and failing homing. When I added a second newline (or manually edited the file so they were on separate lines) that issue went away. Sandify has been awesome btw!
At the moment I’m using LaserGRBL to send patterns to the board, that will probably change as things move to automation.
Noisewise its just a quiet hum and I really haven’t done anything at all.
Here the guts upside-down (on my living room rug, not exactly a static free workbench but oh well):
And with some test baking soda. Trying not to sneeze it all over said living room rug.
For the coffee table part I ordered aluminum angles (3" x 1") from metalsupermarkets.com ($91 plus another $40 for shipping).
The woodworking part will probably take a while since I do most of that at a weekend place outside the city. On the bright side this was the perfect excuse to order that cordless Dewalt router I’ve wanted for ages.