so the blackbox controller uses 24v. i have a meanwell power supply that has 24v output. wondering if it will work, or will i need a new power supply as well? power supply i have is https://www.omc-stepperonline.com/download/S-400-24.pdf. thank you!
Read the DRV8825 design notes from TI, about the PowerPad thermal spec. Heatsinks out the bottom though a soldered pad underneath the chip. A metal heatsink on the plastic top does almost nothing. Keep the bottom of the PCB cool. In practice you'll see thermal cutout around 1.25-1.5A with a fan. Or, get a BlackBox 3.2A RMS (4A peak) its a very different beast
Oh, and do replace your limit switches with our Xtension Limit Switch Kit Onboard EMI/switch debounce filtering is another game changer for reliability. Peruse the BlackBox Documentation at https://docs.openbuilds.com/blackbox to learn all about it all Also see start [OpenBuilds Documentation] for other information, for example more modern software: docs:software:overview [OpenBuilds Documentation] And accessories like Interface https://docs.openbuilds.com/interface or our Probe: https://docs.openbuilds.com/xyzprobe
I actually had a house box fan blowing on mine really close and they still overheated on longer cuts.
so, knowing this is an incredibly subjective and **** near impossible question to answer, but what is the chance that it is not a controller issue? maybe the anti backlash blocks too tight or not enough lube (it seems to be quite dripping by now. i have tried everything i can think of)? just wanting to make sure that dropping $200 to $600 (for all the accessories, of course! ) won't be a waste of money, knowing that i was planning to upgrade in about 6 months anyway. knowing that this will only be mostly a hobby, was hoping to make a few dollars on the side to at least cover my habit!
If you have a couple minutes for a test, dial the current down, blow some air on the controller (desk fan will do) and see if it sounds different
huge progress! i turned down the current limiters, and got the machine running much more quietly! however, on an x axis calibration using 500mm, the longer it ran the more popping was heard. never was able to get popping to go completely away no matter what. i either turned the current down until stall or there was popping, espeically the z axis. also, on a y axis calibration at 750mm it was consistently off at 748.5mm of movement. i'm guessing that means the controller is definitely woefully underpowered and i will need a blackbox? btw the garage is where this is located, and ambient air temp is around 50 degrees so i bypassed the fan, but since it started out much more quietly, and slowly increased in popping noise, there is a thermal issue that is causing missed steps?
At this point, and without seeing it first hand, I would guess it is thermal. The nice thing about a BlackBox -- and I say this as someone who owns one -- is that it will be much easier for customer support, and us, to help trouble shoot it. It is also so easy to set up. The warranty is fantastic, too.
okay. been going through the accessories. much coolness there. however, one question. exactly how many limit switches are needed/used on a normal setup? just the basic 3 for the homing? also, for the homing, should i use one on each y axis, maybe wired together, since i have a slave stepper on each access? or should i get a full set so i have limit switches at all ends, x left and right, y1/y2 front and back and z top and bottom? may have to forgo the limit switches above the homing switches initially. i know these questions are starting to get off topic, and can start a new thread, if needed for these.
so is there any reason why i would need to replace my stepper motors as well, or just the controller? it would be nice to have the entire kit, but then i'd have 4 nema 23 steppers to dispose of. i like the connections on the openbuilds motors. i found some dust caps to put on my existing motors that were 3d printed plastic, and allowed me to use a 4 pin screw on connector, but the openbuilds xtension connections look really nice.
You can add the connectors to the motors you have. They are just screw terminals here: Xtension Connector Sets
Only if their electrical specs are outside acceptable ranges. You want 3-6v coils, low inductance, 2.8-3A current rating. Compare to our motors' datasheets. If coil voltage is significantly higher, the motors weren't meant for a 24v system and will accelerate very slowly If they are high inductance they'll have low top speed (high inductance generates more Back EMF that self-brakes the motor at higher RPMs)
new controller just landed! will be putting it in tonight. i'll update everyone once i get that installed and test calibration. just to be clear, i am running the following distances per axis on the calibration. x axis: 500mm y axis: 750mm z axis: 50mm when i get my starting point set, i zero out the axis, run the calibration and return to zero. once i get back to zero, then i issue the following commands depnding on which axis i am trying to calibrate, and check measurement. G21 G1 X500 F1000 G21 G1 Y750 F1000 G21 G1 Z50 F1000 hoping that when i run the respective command above, it will show much closer than what i am seeing now. if there is anything in this process that i am doing wrong, please let me know. THANK YOU ALL FOR YOUR HELP!!!!!!!!!
Just keep your acceleration / max rate values in Grbl Settings conservative first (get it accurate, then come back and tune for speed)
okay. should i lower that feed rate to say 500? the grbl settings for max feed rates are set to 1000 already. not even sure what the max can eventually be set to.
Trial and error. Like I said, get a reliable result first, then up the speeds little by little. What machine do you have?
lytle special. i took ideas from various builds and created my own frankenstein! it's got a little of several different machines. i used 1,000mm c beam for the x and y axes, and 250mm c beam for the z axis. acme lead screws for the drive, and a separate stepper on each side of the y axis for a total of 4 motors. built my own drag chain carrier for the x axis so it wouldnt' fall down on the work area. z axis motor sits on top of the z axis and moves the entire c beam with a fixed router rather than moving the router bracket up and down a fixed c beam. i used 250mm c beam for the uprights on the x axis. turned the y axis c beams facing out, and have the x axis upgrades on the outside of the machine to keep work area free of moving obstacles, and to keep the open channel of the c beam and thus the lead screws as far away from dust as possible. used a 2 inch aluminum angle on each side of the y axis with 7 points to screw it down to a table that i built out of a 3/4" 4x8 sheet of plywood, and 2x6 frame, so the table is capable of handling me standing in the middle of it. rigidity was my primary concern.
openbuilds. pretty much everything except the controller, steppers and power supply came from openbuilds. the only reason i didn't get the electronics from openbuilds was they were out of stock and had been for some time. also, obviously, the custom aluminum brackets. aluminum from lowes and fabricated by me.
OK so unless your frame is a lot heavier, then OpenBuilds-CONTROL/grbl-defaults.js at master · OpenBuilds/OpenBuilds-CONTROL (LEAD1010 built in profile) may be a good starting point. XY sitting around 2500mm max rates, with 150mm/s2 accelerations - quite conservative (for a BlackBox - if you have terrible drivers, derate accordingly)
well, after tonight i will have a blackbox controller. basically if you take the lead 1010 and change out the uprights for the x axis from the 80x20 vslot to 250mm c beams, you have about as close to the setup i built as openbuilds has in a current machine. at the time, they didn't have the lead machines, and i liked a lot of the aspects of the c beam, except for the y axis. i didn't like the table moving back and forth instead of moving the entire gantry.
just to update everyone, i have a working machine! however, just for kicks, for whatever reason, i decided to check voltage coming out of my power supply. it is putting out 20.8 volts with the adjustment maxed out, so, guess i will be ordering a new power supply! would there be too much harm done by making a test carving? if so, i will just wait until i get the replacement power supply. thank you again for all your assistance! it runs much more quietly, and i was able to duplicate results correctly. once i calibrated an axis, i went through the calibration process a second time, and it duplicated results on second pass on each axis.
