Hello i am building an MPCNC and i have sourced the parts for my machine. Are there any missing parts, or miscellanious parts i should buy?
You can see my cart screenshots here but i cant include a link so i have an extra space at the com and the https
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Welcome! Super awesome to see younger folks getting started building and making. Glad to see you here!
The pictures are kinda fuzzy, hard to make out what’s what and quantities.
The bearings look like they may be unshielded. You might want to consider shielded bearings for this. The router suggests you’ll be cutting rather than lasering, and dust and junk WILL get in them. Might cause some problems later.
Also looks like a solid lead screw coupler. The springy ones are helpful for slight misalignments. If everything is perfect, the solid one will be great. If anything is off a little, you could get binding and missed steps.
Are you considering dual endstops (because ramps)? I don’t see switches, but maybe you have those handy already.
Things i can see :
Nuts and bolts (maybe screws?)
Pulleys
Bearings
4+1 nema 17 steppers
Ramps/drivers/ps/switch
Spindle/ps/spindle control /collets/mount
Lead screw/solid coupler /tnut
Belt
Assuming you have wire, connectors, tools, tube, and a table, a printer, and a table, AND that the specs /qty are correct, i think you’re in pretty good shape.
Now is a good time to think about a cable chain. Pretty cheap to add to an existing order, saves a lot of pain and frustration dialing in printed parts or rigging something up. A lot of folks use the tape measure trick, but my last build was a real cable chain and i like it. I built a few others without, and a couple with just some zip ties, lol.
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Welcome to the forum. Everyone is very helpful here, so if you have any issues with your build, don’t hesitate to ask questions.
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You don’t need the Ramps endstop switches. They won’t work without modification, and they don’t mount easily to the primo. The switches you have further down are what you want.
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In the first image, it does not appear to me that you are buying idlers. Idlers are don’t have teeth. See this link and compare it to the picture of what you are purchasing.
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You don’t really need the AC connector. You can just use a power strip with the switch easily reached to run power for both the motor and the control board…and that way you can quickly shut everything down.
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I second Tony’s suggestion about the coupler.
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Your power supply is a little bit light for the job. If it is a quality supply, you will likely get away with using it, but if it is not beyond your budget, I’d get a 6A or 7A one.
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Personally, I find the Ramps/RipRap display like this one very helpful. You can run your jobs directly from the SD card, and it helps diagnose issues when connecting to a PC.
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If you’ve not purchased it, I would suggest a router rather than the 500W spindle. Comparisons on this forum find the routers have more power and a bit more able when cutting. If you have already purchased the spindle, don’t worry about it.
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I don’t see the specifications of the stepper motor, so I cannot check that it has the recommended level of torque.
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The firmware that V1 maintains is setup for DRV8825 stepper drivers. Your Ramps board comes A4988 drivers. If you want to avoid modifying the firmware, you could purchase five DRV8825 drivers. The modification is simple, but it does require you to setup and use a development environment to compile the firmware.
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Since you are shopping, maybe consider ordering some endmills/bits.
Edit to add: The last time I purchased a Ramps 1.4 board, I went with this kit. While it was a bit more expensive, when it arrived, I was impressed by the quality, and it had higher voltage capacitors allowing me to run it at 24V if I ever want to.
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hello tony. i actually found some shielded bearing locally but they didnt offer a discount on larger quantities so in the moment i sourced this shop and i will call them on monday to find if the have any with a shield. thanks for informing me about the coupler. I thought since in cnc milling you dont want your spindle to flex the solid one would be ok. i dont have a large budget and sourcing all these parts locally is hard. But fortunately since i have a 3d printer and a used spindle for cheap i think i will have it up and running till summer
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Hello Robert thanks a lot for your interest. Y’all are really helpful on this forum. First of all i am thinking about buying the spindle because i found it for 50 euros near me and the routers i have checked cost 150+ here(at least the makita one everyone uses). then i will start with the bare basics for electronics and then upgrade the machine when i have the budget. Either way i have the laptop and it will be pretty easy for me to run the cnc with grbl instead of using an sd card. The screen looks cool and it will be really helpful so i dont need to have the laptop always at the home workshop.
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Ive never ordered from aliexpress but the interface looks kinda like banggod. Is it a similar thing because i have ordered a lot of stuff from banggod and most of them were great.
My comment about the screen is directed at Marlin, not GRBL. GRBL is changing, but traditional implementations using the UNO did not support a screen. I know very little about GRBL, and I don’t know what version runs on the Ramps 1.4 board, and if that version supports a screen. Most MPCNC users run Marlin, but there is a happy minority on this forum using GRBL. My comment about the DRV8825 is also directed to the V1 maintained version of Marlin. It does not apply if you plan on running GRBL.
As for AliExpress, it is an umbrella business for lots of (typically small) suppliers. Shipping times tend to be longer (sometimes much longer) than Banggood, and, since you are dealing with small suppliers, there is more opportunity for problems or outright deception. Typically, you get what you ordered. I tend to stick to stores that have a higher number of sales of the item I want (plus a good rating), even if that means I pay a bit more.
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First off, I’m impressed you got those details out of the picture, Robert. I thought I was missing my glasses for a minute.
For ramps, the grbl version is mega ramps. I use it, and I like it a lot, but since you already have a printer, it likely runs marlin, which makes marlin a good jumping off point. No virtue in learning a second firmware until you need to.
As for the spindle, i couldn’t recognize it either. I’ve read here that the cheaper 500w spindles have rubber bushings that make them run quieter and help with free runout, but once loaded the rubber squishes and effectively turns into a BUNCH of runout. Probably wouldn’t be so bad if you were making primarily foam parts, but it leads to a lot of chatter before you even get to cleanup passes.
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the grbl version is mega ramps.
Does this firmware support a screen?
It does not. No headless running as far as I can tell, either. Marlin is a big winner there. I guess the newer grbl work, grblhal, has all the good stuff, but I’m not motivated enough to change direction.
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can i run marlin on the mega that comes with the banggood kit. And about the GT2 idler. can i buy a timing pulley with bearing on the bore and remove them with a dremel?
can i run marlin on the mega that comes with the banggood kit.
Yes. V1 maintains a version of the firmware for this board/mega combination. You can find it on this page. The pre-built version expects DRV8825 stepper drivers. Your kit comes with A4988 drivers, so you will need to make a simple change in the configuration.h file and recompile the firmware. See the PlatformIO page for instructions on how to compile the firmware.
can i buy a timing pulley with bearing on the bore and remove them with a dremel?
I don’t know. My concern would be clearance, not functionality. I think I read a post some time ago where someone 3D printed some idlers, but I don’t remember how well (or if) this worked.
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I’ve only done that once with some pulleys, except i tried pressing them out. The brains were pretty bad so I thought I would replace them.
They must have been glued in or something, because I mangled the pulleys so badly I couldn’t use them. I don’t know if that’s typical. I’d think the bearings are tough to dremel out, but I’ve never tried it.
No i dont mean the bearings. I meant to grind the teeth of the timing pulley so its like the one reccomended. i said the bearing because most pulleys have an insert and a bolt and that would work as a timing belt. (im sorry for my bad english)
Seems like it would be pretty easy to make it out of round, but I’m just guessing.
Also seems like it would work ok as is if thats all you can get. I can’t imagine how running teeth alomg the back of the belt really hurts much at these tension levels, but again, big guess. I’ve seen some home brew 3d printers run that way with no problem, but if course the loads on a cnc are much larger.
Hopefully someone who actually knows what they’re talking about will come along shortly.
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