I was wondering if you could see my recent instagram post and story about making my own cnc.@floppyarduino. I wanted to see if you guys had any tips, tricks or suggestions for this ie:frame design, mounts things like .This is my first real big project since I do small electronic things. I'm making a cnc router and wanted to make it as good as it can. Ive got the electronics done pending the e stop switch and will start the frame later on maybe next week or over the holiday break. Thanks.
A very broad question, which makes it VERY difficult to answer. But I try to list a couple of pointers: - Match your machine to your work. If you're only going to be making small parts, get a small frame. The longer the axes, the more they flex. Also, realize the limitations of hobby machines. You most likely won't be milling nickel-based superalloys at high speeds, or making perfectly round wheels like on a lathe, but you can make a lot of things with a hobby machine. - Don't go overboard on your chosen steppers. Since you have those small, chip-sized drivers, you're pretty much restricted to something like 1A(?) of current, so no point in getting huge 5A steppers. You gain nothing from the extra headroom, quite the contrary. To use beefier motors you'd need better drivers, and at that point I'd suggest you read on the subject (inductance and the surprisingly high voltages you should run with those stepper motors). - Interference prevention. Your photos show your stepper wires being separate normal wires, which makes them prone to transmitting and receiving interference, ergo causing problems. This mostly comes up with using hard limits, where you may encounter false triggering. This is largely due to Arduino Uno supplying 5v signals, which are suspectible to interference. Shielding helps, ferrite cores help, twisted pair wiring helps, pull up resistors paired with capacitors help, and opto-isolators help. You can use one or more based on your needs. I've personally given up on hard limits due to having had to scrap parts due to false hard limit triggers mid-part. - Plan your dust/chip extraction. If you don't, you'll have your room full of dust and chips in no time at all. This may, or may not, concern you. There are, however, a plethora of enclosures and dust extraction implementations out there. There, some pointers and things to consider when building. For a general suggestion, the usual "Get the Lead machine" will not let you down. Regards, Will
Thank you. That helps. I will adjust the limits as you mentioned. i will be using shielded twisted pair ethernet cables to extend the stepper wires since they are not long enough from where my control box will be(using each 1 of the 4 twisted pairs as 1 conductor so 4 conductors per cable. I will be buying the wood and metal for the frame this weekend and my machine build volume will be about 26" × 26" × 6" Thanks
I would strongly recommend a proper controller; BlackBox Motion Control System Those little chip drivers conk out from overheating around 700mA (-0.7A) which is ridicously little power. BlackBox can deliver 3.2A RMS with 4A peak power! You can't run a CNC on that little, you need good torque to resist cutter forces
Thanks for the suggestion. That will need to be a future upgrade. My budget is tight for this build right now but I will improve it as time goes on. My money right now is a bit tight
