noob making my first cnc machine

So this is my first CNC project, i'm a high-school student and i thought this would be really cool to make.

So I have a few questions.

Is have to have stepper motors or will regular dc motors work

I understand all the mechanical setup of the CNC but what im having trouble with is how to control it.

Can i just connect the motors by wire directly into the back of my computer in the parallel port? I've heard that if its wired wrong it will fry your motherboard.
But as long as I wire it correctly it should work right?

then is there some specific software that is needed to control this?

Ive seen some people who have a separate board or 'driver' i guess. Is this needed? also how can i protect my mother board from getting fried?

thanks guys

Note: i wont be using this to mill full on metal or aluminum or anything like that its just kinda a project to get my foot in the door so to speak, and learn how to build a one properly.

To control the machine, you need Control software, like Mach3 (Windows) or LinuxCNC (Linux).

The control software sends step and direction signals to the drives, which send power to the motors.

You can use either stepper motors, or servo motors with encoders. regular DC motors will not work.

To make interfacing the drives to the PC easier, you can use a breakout board. Some offer isolation, which can prevent damage to the PC if you wire something incorrectly.

In addition to the control software, steppers, and drives, you also need a power supply to provide power to the stepper motors. This is typically a DC power supply between 24 and 48V, though higher power systems can use higher voltages.

so you obosulutly have to have drivers, you cant just directly connect the motor wires into the port on the PC? by drivers does it mean physical circuits or boards or software?

What are the chances of frying my mother board? I dont have money or/and parts to make a board or any other circuitry.

Examples of Stepper drives:
G540 4-Axis Motor Control

HobbyCNC | CNC for the desktop machinist and hobbyist.

Not recommended, but cheap: CNC Router 3 Axis 3.5A TB6560 Stepper Motor Driver Board For Engraving Machine | eBay

ok thanks for the link, i guess there is no way around using a driver.

I found this tutorial somewhere that used a floppy drive to as a driver. here is the link -->> Controlling Floppy Drive Stepper Motor via Parallel Port - CodeProject

Quote:

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Originally Posted by mrn

So this is my first CNC project, i'm a high-school student and i thought this would be really cool to make.

So I have a few questions.

Is have to have stepper motors or will regular dc motors work

[Regular DC motors will work, as long as you fit encoders to them so they can keep track of their position. Otherwise, they just spin out of control.]

I understand all the mechanical setup of the CNC but what im having trouble with is how to control it.

Can i just connect the motors by wire directly into the back of my computer in the parallel port? I've heard that if its wired wrong it will fry your motherboard.
But as long as I wire it correctly it should work right?

[No you can't do that. The parallel port only puts out 5 volts (at most), which is fine for controlling logic-level things, but isn't nearly enough for CNC motors. And yes, there's a good chance you'd fry something if you tried this.]

then is there some specific software that is needed to control this?

[Yes, most people here use Mach3 or EMC (now LinuxCNC).]

Ive seen some people who have a separate board or 'driver' i guess. Is this needed?

[Yes. Everybody using computers to control CNC machines uses them, not just some. You may be confused by something you've read (or watched videos about) where tiny servos are controlled by simple H-bridge circuits, but those are much smaller motors than are used in CNC machines. ]

also how can i protect my mother board from getting fried?

[Most breakout boards (which deal with the outputs and inputs to and from your computer) use opto-isolation to protect the computer.]

thanks guys

Note: i wont be using this to mill full on metal or aluminum or anything like that its just kinda a project to get my foot in the door so to speak, and learn how to build a one properly.

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[It can be done, but it's not quite as easy as simply plugging motors into the back of your computer and expecting them to drive your machine.]

Andrew Werby
www.computersculpture.com