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laranjas3
12-10-2017, 06:59 AM
Hello guys,
I already had build a 3D printer in 2013, I started to get bored with it, so I start to see some CNC videos on internet about CNC routers and I thanked: I can do it!!!

So I made a little research about homemade CNC's and I find out that I will need:
-Control system
-Stepper motors + drivers
-Transmission (belt's + pulley's)
-Ballscrews
-Linear rail/rods
-Metallic structure
-Spend little money as possible

So after that I went to my backyard and I found some 50*50mm steel tubes, perfect for the structure!
I went to the scrapyard and I found some aluminium tables with 15mm linear rails that looked perfect for X&Y axis and a linear structure with 20mm rod's that was good enough for Z axis.

I searched on ebay and found Nema 23 with 270oz-in with TB6560 driver + 24V power supply and mach 3 interface for a reasonable price.
The belt's and pulley's were ordered from www.bepltd.com, very nice guys, aluminium pulleys with 20&40 teeth for 1:2 ratio and HTD 3M belts, perfect for very small or no backlash.

After some time I found out my computer was not able to connect to Mach 3 interface via LPT1... So was time to search for USB solutions, and i found GRBL.
After that I ordered a One CNC V3 and an Arduino Uno from Ebay, perfect for the job.

After lots of welding, drilling, tappering, ect the cnc was running perfectly, almost squared!!!

At that time I explored the limits of the machine, and i find out that I abused with microsteps. The machine was too precise, too slow and with almost no torque.
Time to do some research:
-Calculation torque Vs microsteps & step/mm to achive resolution Excel link:
https://www.dropbox.com/s/lhz4ht3kh0cstjp/Motores%20e%20eixos.xlsx?dl=0

With this excel I understand why we should not abuse of microstepping, and why is important to choose a pretended resolution to you CNC machine.
An important factor is also driver voltage, TB6560 only are able to have a input voltage of 30V, this is a limitation to achieve max torque at higher stepper motor speed.

Spindle was a a very difficult choose since I don't really know what the machine can handle, so i went for 0.8kW+VFD chinese spindle water cooled from ebay, now I'm a bit regretted due collect 11 isto small(max 7mm mills).

Material:
CNC Structure & Parts
Steel tubes: Backyard
Aluminium parts: Bought on junkyard
Fixation: Welded steel tubes & screws

Linear rails: Came toghether with aluminium plates
Linear rails X&Y axis: 15mm wide
Linear rod Z axis: 20mm

Stepper motors: Nema 23 76mm 270oz-in (1.6N-m)
Driver: TB6560 + 24Vpower source
Control: One CNC V3 + arduino Uno + GRBL

Ballscrews: 1605 (16mm & 5mm/rot)

Belts & Pulleys:
Ratio: 1:2 (20x40 teeth)
Belt: HTD 3M 9mm wide

Spindle & VFD
Power: 800W
RPM: 24000
Collet: ER11 (max 7mm)
Water cooled

23018
23019

So enough of talk and lets see the machine working!!


https://youtu.be/tHMQ5T7rxrM

Next steps:
-Add endstops X,Y & Z
-Mill Aluminium Spindle brackets
-Protect rails and ballscrews from chips.
-Make a box for CNC (maybe soundproof)

I know this is not a perfect CNC, but for the first one I'm proud of it!

If you have any idea or improvement please share, Thanks.

Clive S
12-10-2017, 09:50 AM
Welcome to the form.


If you have any idea or improvement please share, Thanks.
Change your drives to AM882's and up the PS to 68V

laranjas3
12-10-2017, 10:48 AM
Welcome to the form.


Change your drives to AM882's and up the PS to 68VWhat kind of improvement this will bring? More speed & torque?

Thank you

Enviado de meu Redmi Note 4 usando Tapatalk

Clive S
12-10-2017, 12:20 PM
What kind of improvement this will bring? More speed & torque?

Thank you

Enviado de meu Redmi Note 4 usando Tapatalk

Yes, and they will be good for your next build:barbershop_quartet_

laranjas3
15-10-2017, 08:26 AM
Hello guys,
So I'm doing 2 Aluminium brackets for my 0.8kw spindle.
23046

I could do it by milling an aluminum plate, but long time ago I want to make a full video of lost PLA on plaster mold for aluminium casting.

So how I will document this:
Part 1:
-Fusion 360 modeling
-Slic3r Gcode generating
-3D printing
-PLA welding with soldering iron

Part 2:
-Make of plaster mold
-Dry of the mold & melt of PLA
-Aluminium casting

Part 3:
-Fusion 360 CAM
-Mill the aluminium bracket to the spec


Here you have the first video (Part 1/3):

https://youtu.be/C3L2OKaxrOU


Any idea os suggestion?

Thank you

laranjas3
29-10-2017, 07:57 AM
Hello guys,
Today I completed the part 2 of the video, the plaster mold preparation and aluminium casting.

23114


https://youtu.be/TYHwJguXLYY

I hope you enjoy.

Thank you

laranjas3
04-11-2017, 06:45 PM
Thanks for the comment!

I tried to mill the parts yesterday with some drawbacks:
-Too much RPM & worn out tool
-New tool with 12k rpm milled the aluminium with goos quality
-M30 at the end of Gcode that broke my carbide tool -_-

The CNC broke the mill with lots of class!

Check the video:

https://youtu.be/HhIX-PMxbrE

Thank you guys.

laranjas3
16-11-2017, 09:18 PM
Hello guys,
Finally I used the CNC to mill the spindle brackets, I hope you enjoy:


https://www.youtube.com/watch?v=QxhSPz0AKqM&t=22s