Thank your for suggesting cncjs. It seems much more stable that UGS. So far no crashes and I am able to do some initial testing with much less frustration. I only wish I knew how to define custom macros to have a window displaying the limit switch state, as that as currently where I’m at in getting set up. I need to tweak firmware settings to get it all working correctly. Default for what I’m using is set up for NO and I have my limit switches wired for NC. I think I’m getting close to figuring it all out. Found out yesterday finally after much head scratching, one y drive was moving weird, that the whole time my problem was a bad stepper driver that was only putting out 2v instead of 12v to the B coil. So I have a new one delivering tomorrow and then I should have smooth correct movement. Then I just need to change all my step/mm rates and max travel parameters to get correct scaled movement, etc… Excited to finally get things going! Video series to come soon to youtube. I plan on sharing a lot of what I’ve learned along the way and wish I had known sooner lol. Should be some valuable info for others looking to build one.
You took a very hard road. One not all that many of us have experience with. Marlin and the suggested software and you would be up and running already.
Any of us that have experience will try to help along but it will be significantly slower going.
No worries. I’m enjoying learning more about all the little things involved. I intentionally didn’t want a plug and play solution. I want something totally customizable and upgradeable. Having to figure everything out I don’t mind at all. By the time I get through it I should have a lot of knowledge that can benefit others. I plan on sharing a lot of it in the youtube playlist I’m making for anyone interested.
I get that, but I still like a solution where basic works, then I start to change stuff. In that way, I get to learn about what I changed and how each piece works. Still for a major change like different firmware, it’s hard to do that gradually.
The biggest down side I see is the drivers you chose have a very course current adjustment. You are either going to run extremly hot, or low power.
what do you mean by this? can you elaborate?
Coarse…
As in not fine control. It is very difficult to get control in very small increments for those little potentiometers. I’m usually happy if I can get within 150mA of my target current on those.
I understand the coarse v fine control, I don’t understand running hot or low power. I am using external tb6600 drivers… no potentiometer. I set the peak current through dip switches. What is the issue here?
Whoops, Coarse…spelling is not my strong suit even with grammar checkers.
You can set your drivers to, " (0.5A, 1A, 1.5A, 2A, 2.5A, 2.8A, 3.0A, 3.5A) " .5 is too low, 1A is probably too high, be careful. at 1A your steppers could get extremely hot, at 0.5A your drivers could be extremely weak.
I looked them up and I saw they have a max current rating of 2A??
You can’t run them at max all the time, that is a peak rating not an average. 1A might be okay but I suspect 1.5 is going to be too much.
It will work, that is just a huge downside to those drivers. The drivers we use allow for single mill amp adjustments instead of 500ma steps, allowing for dialing in the power to our needs very precisely.
I tried to run Marlin firmware today with no luck whatsoever unfortunately. Can you tell me… By default in V1CNC_Ramps_DualLR-2.0.9.2.zip the Rep rap full graphics LCD is enabled. Does this override being able to receive any g code instructions from UGS or cncjs? Or should they both be able to work simultaneously? I have not gotten to hooking that up yet as I still need to figure out the pinout (not using a ramps shield) and a mounting bracket for it. I tried commenting that out but I had issues getting it to compile. So I had to load up the .hex file and that had no response for me in cncjs. I have been playing with GRBL-mega-5x and am pretty close to operational with that, and I followed the default pinouts which correspond to the ramps 1.4 shield I believe. There are so many more files in the Marlin firmware I don’t even know where to begin looking to find out the pinout it is set up for.
No.
You use one or the other, but nothing is needed to be changed in the firmware.
Why not, for a few dollars you get a few mosfets pins, power, grounds and all the documentation is laid out.
The pinouts will be for the ramps shield, not the UNO. Here is the UNO pin out. File:RAMPS1.4schematic.png - RepRap RAMPS 1.4 - RepRap
I am not actually sure how to help. Marlin is nothing special without the shield, external drivers take away most of that specialty. I am not sure why you want to use externals, or what your end goal is.
I changed my drivers on a printer today from 725ma to 750ma to balance power and heat. I absolutely would not want to give up that kind of control unless you have a realllllly good reason.
I may change courses if needed. But I have movement and everything so far with GRBL, just homing is still an issue for me to get solved. Of course I haven’t cut anything yet so TBD if power and heat is going to be a problem. Originally I leaned toward external drivers with the mindset of being able to convert to bigger steppers at some point in the future either on this machine or another. I am just now realizing that I am using the mega 2560 and the UNO has a different processor. I had to use a different version of GRBL to work with mega, probably I would need a different version of Marlin as well? Does such a version exist or is it only configured for UNO or other arduinos with the 328p processor?
The documentation you linked seems it is set up to work with mega, not sure if I need to change something in the firmware though from your premade config if that is set for an UNO.
Marlin works with the mega (the ramps is based on mega). I don’t know if Marlin would work on an uno. It works on a ton of other boards though. Grbl (the main one) is only uno. GrblHAL or grblMega are forks, and they work on different cpus.
Pleased to report successful homing after installing RC low pass filter on my limit switch inputs! Just need to get a few more things dialed in and run some tests and hopefully soon making my first cuts.
Still trying to find a way to customize the homing pulloff for the cloned axes for auto squaring. Looks like this isn’t a feature in grbl 
Unless i just havent found the command yet. Maybe I’ll write some code or overcome this with some kind of shim on the stop blocks or bending the limit switch arm. More reasons to go to Marlin lol.
Hey all. I’ve been tweaking max speed and acceleration settings, it seems I can set them pretty darn high without a problem, but I think they probably shouldn’t be that high for safety. Just curious what sort of settings do you all have your machines set to?
That is a tough question, one I used to never even respond to. Keep in mind this is only for Rapids/travel. Cutting will never be this fast.
Find your max speed and back off considerably, probably even 50%. That will keep your power high enough for safe fast travel moves.
As for acceleration, do not turn it up very much if at all. You do not want your router bouncing in corners. If you really want to test this, find some scrap, or even foam and mill some triangle pockets (abrupt corners) and adjust your accels. Mill faster than you normally would by a bit 10-20% and adjust the accels. You would be looking for a corner overshoot. In 3D printing you would get ringing, it is the same here it would show up as wavy inside corners (all corners would be affected, I just think you will see it most in inside ones). Post some results if you test this.
Aggressive accels will be for more likely to cause skipped steps. Think about what the router is doing when an accel happens. The bit is buried doing something like a 45% step over until it hits a corner accels and also happens to be buried momentarily in an 80+% step over while it turns. You need the most power at this moment.