Upgrading My 3D Printed CNC Router!

nice, thank you

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.

you can look up the feedrates and stuff for your specific tools, there should be a recommendation from the manufacturer

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 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

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.

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

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 👍

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 .

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

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

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.

To mill aluminum on a cnc machine that is lacking stiffness look into trochoidal milling techniques.

Maybe upgrade to a Printnc mini

Feed per tooth is very important when milling aluminum, NYC CNC has a very good video about this where they tested it on a shapeoko

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.

Just checking-out your BoM. Should you not have 2 lineaq bearing sets and 4 blocks? Also, where does the 2020 extrusion go? Thanks.

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

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.

that intro was amazing

Add to the 'cart' but where is the 'cart'? Poked around for awhile then left.

Which taps are you using?

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 !!! 👍

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

Have you abandoned Discord?

thumbs up and no nasty comment

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.

For milling aluminum:
1: I would buy shorter endmills and also clamp them as short as possible.
2: Take single flutes endmills with DLC coating. Or 2 flutes DLC with a low pitch (if you have problems with vibrations).
3: I'm using isopropanol alcohol with compressed air for cooling and lubricating the endmill, which works amazing!

You dont have to tap the holes at the end of the extusions, a screw can form the thread just drive it into the hole.

Do you have plans to rework the printed parts in Aluminium with the printed CNC to make a better machine? How does this compare with the 150 and 500 dollar machines you reviewed?

I have quite a bit of experience (successfully!) cutting aluminum on my DIY MPCNC. I only use single-flute, carbide, upcut bits (mostly SpeTool bits from Amazon). I don't use lubricant, only occasionally some IPA spray to cool the bit on long cuts. You're not going to be able to get large chips on one of these machines -- tradeoffs have to be made. In this case, I choose higher RPM to shift cutting power from the XY motors (weak) to the spindle (a lot stronger). But the high RPM generates a lot of friction/heat, which is why you want to try to keep flute-count low (single-flute) and feedrate up.

For most operations, you want "trochoidal milling", which if you're using Fusion360 CAM is part of "3D adaptive clearing". Adaptive clearing is really magical, as it optimizes for consistent tool-load. So once you dial in the settings, if it works at all, it should keep working as long as the tool doesn't go dull. Here's what I use most:
-- 1/4" (6.35mm) diameter single-flute carbide
-- 22,000 RPM
-- Feed: 600 mm/min (~24 ipm), climb milling
-- Depth of cut (DOC): 4.0 mm
-- 10% optimal load (0.635mm stepover)
-- Ramp: helix @ 2deg
-- If you have trouble, scale back stepover first, then depth of cut. Try to keep feedrate up, otherwise you generate too much heat.

For contouring, you can do adaptive/trochoidal for your contours but it will literally take 10x the amount of time as doing a regular contour. I swear by traditional contours using a 1/8"-with-1/4"-shank single-flute carbide endmills (excellent for rigidity). My magic numbers for this are:
-- 1/8" (3.175mm) single-flute carbide
-- 26,000 RPM
-- Feed: 400 mm/min (~16 ipm)
-- Depth of cut: 0.4mm
-- Lead-in/out, no ramping

One pro-tip for cutting aluminum plate contours: Setup a contour operation as above with 0.2mm radial stock-to-leave (0.4mm DOC). Then copy the operation, only changing stock-to-leave to 0, and DOC to 4mm. The first contour cuts the part slightly oversized, the second one only removes the last 0.2mm in 1-2 passes, which leaves a super clean surface finish.

You suck! You didn't share if your modifications worked! So people can't follow you and then waste time and money

Which program do you use to create the g-code?

Thanks for the video and the files

ally is good, 1 flute up cut, 18000rpm, some lubricant. keep the stepdown low and the feed low. id do 0.5mm steps and 1500mm/m on mine but its also big and a bit flimsy. nice little machine, id love to see you upgrade it further.