A new update on my DIY CNC project.
I have moved the Y-rails from the top to the sides + designed the gantry.
The X- rails is mounted on two 20x70mm alu plates + a 6x225mm alu plate.
On the gantry sides I plan to use a 11mm alu plate + a solid 40x80 profile
Hope this is going to be a solid/stable setup.
Next I have to add the y-screws + the z-axis.
Very pretty! As my daddy would say “Built like a brick shithouse”
Thank you!
When the design is ready, I have to research whtat steppers and electronics to use with this setup.
I think the linear guides are better on the sides. But I did not want to say anything before. That is usually where folks put them though. Now you have bearings 360 degrees.
On the z-axis I plan to use 20x150mm alu plates.
Hope the end resut is a stable CNC setup.
One Sexy looking machine!
I have a Toshiba 1.5Kw VFD I plan to use on this setup, so a 1,5Kw spindle.
Nema 23 (do not know what oz yet)
24 or 36V PSU + a 12V PSU
Controller - ?
Stepper drivers?
@Oyvind_Amundsen
you have quite an education ahead of you to understand the mysteries that are stepper motors. Stepper motors work backwards to what one would intuitively think. The faster you run a stepper motor the less current it draws. So the weaker it gets. Now there are ways around that. Those ways you need to learn about too.
The most popular way is to run high voltage with current limiting drives. At some RPM current is going to drop off, but the higher voltage you run, the later current drops off. Then there’s understanding the different types of stepper motors, and choosing the ones that will perform the best where you need them to.
Some stepper motors make a lot of torque at low RPM, but struggle to go very fast. They can have very impressive holding torque specs. Which means they stand still great (not terribly meaningful). Other stepper motors can run fast, and make pretty decent torque at higher speeds too. Those are generally the more prized motors in the CNC community.
Unfortunately just looking at holding torque alone won’t spot those motors out. The better performing motors have low voltage ratings (meaningless, besides determining the motor’s characteristics - we use current limiting drives), high current (volts times amps equals power), and low inductance (the secret sauce). Studying torque curve charts helps too.
Agreed with Paul, been watching the design unfold, waiting on the rails to move the the Z plane. The drive mechanism will be easier to integrate this way. Modeling skills are TOP NOTCH. Dump any use of acrylic, just opinion. Maybe look at an 800w. Go ahead and start planning the ACME or ball screws now, you will need to revise X and Y plates to accommodate.
Nice drop of advertising above…
