Thanks for watching! Make sure to check out the full CNC build video here! DIY 3D Printed CNC That Cuts Metal! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ecnLeg1wIx8.html
I'm currently learning to mill aluminum on my MPCNC and I've gotten encouraging results with the following settings: 1/4 single flute end mill, trochoidal milling (or fusion 360's 2d pocket), 22k RPM (Makita's number 4 power setting), feedrate 550 mm/min, 0.0254mm chip load, 50% radial depth of cut (i.e. 3mm), 0.25-0.5mm step down (axial depth of cut) and 25% ramp feed. I did also try 1/8 single flute but it did worse. Understanding chip load (or feed per tooth) was definitely the key to success.
Closed loop steppers and a good controller (Masso, Acorn etc.) will eliminate the problems with skipping steps or at least either self correct or pause the program allowing you to restart a few lines back in the G-Code. A real spindle can give you torque at slower RPMs. Those would be my biggest recommendations for upgrades.
You should consider switching to nema 23 steppers from nema 17s. I did the same on my cnc and it made a big difference. Also, when cutting aluminium try setting the router as slow as you can for me it was around 1.5 on the makita while using a single flute 👍
Thanks for the aluminum tip! I thought about nema 23s for this build but I wasn’t sure if I they would work with the Arduino CNC shield. I do want to build a printNC some day and for that I’ll definitely go with 23s!
You should change all your endmill to single flute . Single flute endmill works so well on aluminium , it does not need oil or enything to get succsesful cut with aluminum . I have the same issue as yours when i build my first DIY cnc machine . Hope my tips help you , great machine build BTW
Thanks for the input! I have a 1/4” single flute endmill that works great for aluminum but I guess I’ll need to try to find some 1/8” ones. Thanks for watching!
milling aluminum with such a high rpm spindle is a nightmare. it is possible however, you need the axis movement speed to match the spindle speed (move much much much faster to avoid chip welding an heat build up). I couldn't tell what endmill you had but try a single flute. aluminum n3ed to be ejected out of the cut as soon as possible especially if dry cutting. Try the lowest rpm in the router but I almost sure you will not be able to successful cut aluminum in that setup. What you can probably try is micro endmills such as 1/8", 5/32" etc. These micro endmills are rpm hungry as apposed to larger endmills and with the lack of rigidity in this setup, you'll probably max out there in terms of metal cutting. There is a fine balance between rigidity, spindle speed and movement speed. You just have to figure out what youll be doing with the machine, mainly, and move on from there.
Thanks for the great tips! I have a single flute 1/4” endmill that I had success with, but the holes in these plates were too small, so I tried using a 3 flute 1/8” endmill and with that in mind, what you said makes total sense! Would you recommend using lubrication or just getting the feeds and speeds down right?
so by switching from a single flute to a 3 flute you tripled the chip load on the tool.. probably making it clog up, lubrication can help, or rather a coolant. research your chiploads for the tool you're using, you'll cut ali clean soon enough.@@ModernHobbyist
my personal opinion, it would be much better to move the X axis motor out behind the gantry and move the spindle as close to the gantry as possible. this will help with rigidity, and that will help with your aluminum milling. Speeds and feeds are critical with aluminum as well. being as the machine is just not super rigid, light cuts will also be required.
Thanks for your thoughts! I considered making more changes to the X axis motor assembly, but opted for the lazy route of integrating with the existing system instead. I've considered rebuilding the entire machine with lead screws in the future which would bring the z axis closer to the gantry, but that'll be one heck of an overhaul!
@@ModernHobbyist oh, zero lash lead screws or ball screws like you use on the Z would be an absolute game changer! But for now, try this; you're running into a tool pressure issue so try dropping to a 1/8" endmill if you have not already, and slow down your feed rates. To keep the chip load high enough while reducing tool pressure, try a o-flute endmill. drop your depth of cut to some fairly low numbers, maybe .050" or even .020" with a 50% stepover. you might have to drop the spindle speed as low as possible too. try to keep between .0008"-.001" depth of cut per flute. I'm telling you though, the o-flute or single flute cutters are a total game changer. if you can keep the machine from flexing while keeping a good chip load, it will do amazing.
@@MonkeyWithAWrenchI’ll give all those tips a shot! I did drop to an O flute 1/4 endmill for cutting acrylic and it absolutely chewed right through it with almost not chatter or issues. It was awesome!
there is a product called Tap Magic for aluminum. it is hands down the best cutting lube for aluminum i've ever used. smells a little like cinnamon. 35 years, 20 of it running my own shop with my homedone bridgeport conversion CNC and everthing else, and we buy it by the gallon. nice vid - about to build a cheapo gantry CNC, so wanted to look at your rail system.
Thank you! I tried using some tap magic actually but wasn’t sure if I was helping or hindering. All the chips seemed to clog up in the slots rather than ejecting like they did when dry 🤔
Hi! If your machine does not have sufficient rigidity for milling Aluminum you should try these settings: Depth/Pass 0.15 mm ; Plunge rate 200 mm/min ; Feed Rate 2000 mm/min ; Spindle 12000 RPM (All settings are for a 4mm Diameter, 3 Flute Aluminum Cutting Bit) but you can adapt for the bit you use This are the settings that i personally use for my Wood CNC Router. (And yes, is made out of wood ) GOOD LUCK !!! 👍
Mostly youre just using the wrong tool. Speed looks fine. Try O-flute or stright flute. Personally my feeds and speeds for a 1/4 o flute ( probably way to big of an endmill for this thinggy) Is 400~500 mm/ m DOC should never exceed 2mm on a small machine like this. plunge and ramp is low, like 250. Always conventional milling 1~2° ramp and spiral And if i want to use more flute i just multiply this base stuff by the flute count. I also use fusion360 which kinda just makes this easy. Ive desgined and built my own cnc, it took like a full year of messing with it before its final construction. My biggest issue with 3d printed cncs is they dont use enough plastic 😄 For my cnc all parts are like 80% plasric by volume. The gantry is super heavy, the tool head is heavy af. These light machines are toys, but your spindle is doing most of the work. Switch the router out for a spindle and youll get better results. Even a cheap 500w I have a cheap 500w spindle on my cnc and it does pretty much everything ive wanted to do. If i enter from the side of a peice of aluminum i can take a 3.5 to 4mm cut at about 300 mm/m. My frame is ridged though. Youll probably only be able to do 1.5mm deep passes. Best advice is to do a bunch of small test cuts until you figure it all out. Get you some stock and just cut shapes. Square pocket, hole, and then contors
if you use a higher voltage on the steppers, they will have more torque and be more powerful. You will want bigger stepper drivers because the ones you have are tiny. Some people can get up to like 60 volts but 24 is a good amount
I’m curious how that will affect the motors heating up and if having them attached to plastic parts would be a problem 🤔 I’d definitely like to start messing around with more intense upgrades to the machine though so this is helpful info, thanks!
@@ModernHobbyist it will definitely put more heat into the steppers. for the parts that interact with the motors, you might want to print them in something more heat resistant than pla. something like petg or asa will take a lot more heat to soften than pla. If the motors are already quite warm it might be a big problem, but if they are cold now, it probably wouldn't be too bad if you put more voltage
Good catch! Needs 2x MGN12 rails (which come with one block) and 2 additional blocks. I've updated the BOM. The 2020 was initially to be a horizontal brace between the 2040 extrusions, but while building it a decided it didn't need it so I left it off but forgot to remove it from the BOM 👍
if you loosing steps that simply means your single steppers in most likely cross table axies is too weak to resist the pressure of your work you have 2 options, either get bigger motor close to maximum of 2 A your driver can handle or double it up and add another stepper driver in paralell to the existing one, i think only jumpers for microsteping, and outputs have to be separate for each driver, pins like power rail direction and step count can be unceremonially rewired to multiple stepper drivers, you could do it with your existing double steppers on the across the table axies too if that start skipping also the faster you spin a stepper motor the less torque it has so keep it in mind also tune your steppers current with thermal probe if you give them enough current they be simply getting warm, if you give them too much current they will start getting hot and maximum torque is somewhere in between, but take into consideration that above 1 A your stepper drivers usually need a fan even if they are rated to up 2 A
The stick out on your endmill is far too long, and all that extra rigidity is lost in flex on endmill try and find a single flute with geometry to cut aluminium reduce step-down a little and it will cut fine
bro at least add lead screw or ball screw at x and y axis it will give machine little more rigidity. and assemble x axis extrusions to one single plate it provides better rigidity to machine
All good thoughts! I have a Fusion360 design to do exactly that (regarding the ball screws on X and Y), but the cost to upgrade and the work required would justify an entirely new build rather than an upgrade. I may make another DIY machine with ball screws and more thought put towards rigidity, but for now the machine can do what I need it to 🤷🏻♂️
Build a CNC machine to learn more about building CNC machines. Upgrade the CNC machine so you can use it to mill new CNC machine parts for itself. This is my kind of making. Fun and pointless
Why not just make it bigger to offset your issues with parts taking up axis realistate. The same X tube aluminum can be frame bolted to sections of the plastic you feel may flex or bend. Its not a high speed machine, inertia doesnt matter, so you could build it as big and strong as it needs to be. Hell you can make plastic cnc machines mill steel if you reinforce them to ludicrous extents. The idea of making your own cnc is not to make it minimalist and "clean" its to emulate the real deal but with pennies instead of dollars.
I myself have barely any Aluminium Cutting Experience ( like a single Project ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-AQ27ZcNx_eM.html ) but from the looks of it I'd guess you're either a) using the wrong type of Aluminium b) an unsuitable Endmill or c) the wrong Speeds / Feeds with my personal guess being a) and c) having a very high involvement in the matter because of the existence of those raised burrs I'd like to think of as an indicator of the Aluminium either being the type that likes to gum up ( acting more like soft butter than hard wax thus gumming up the Cutters ) or your Endmill being dull thus essentially only rubbing along ( the dark tip of it reminds me of an HSS Endmill I once used on MDF instead of a Carbide Tipped one subsequently ruining it as it burned out )
CNC printed is an oxymoron like a battery-powered tank for an army . Design of the X and Z axes is a tragedy . It looks nice in theory, but in practice it's worthless . CNC for aluminum should be at least made of strong aluminum (20mm or more) but best will be stell and gantry construction . the cnc you showed is a toy .
