really cheap and easy to build cnc milling machine/engraver

[ryan0]

I've made all the parts to build one of these:

http://www.youtube.com/watch?v=6drMZqmyXQc

here's the instructable:
Instead of the weird drain pipe he used for the stand on his,I'm using chromed square bar instead for aesthetic purposes.

Also instead of using a dremel to cut,I'll be using a 1w laser diode,the stepper motors I'm using won't be able to handle the vibration of a dremel.But if you're willing to shell out for some heavy duty stepper motors then you can build one just like in the video.
Mine willbe finished once stepper motor controller arrives and I get everything set up.

Total Cost:
50 euro's

this comprised of:
laser diode (engineering teacher gave to me) - free
railing,bearings,couplings,stepper motors (taken from printers) - free
perspex,chrome bar,fibreglass (given to me by my engineering and design teacher) - free
leads (already have) - free
software (hacked) - free
stepper motor controller - 50 euro's

These look really great and are meant to work perfectly,and also they are small enough for your desk.
I'll be finished mine hopefully by friday,anybody who is capable should build one too,as they are cheap enough for anybody to build!And they are SOOOOOO useful!!!!
Go on,have a go at it!

[Alien_X]

It is cool how cheap that cnc "mill" is, but it is also severely limiting, slow, unstable, somewhat poorly designed - transmission nut and slides, the list goes on.
Interesting that you are building one though, let's see pics!

Also, the laser diode won't work the way you want it (from what I have seen/read), a laminate trim router would be much better as a mechanical spindle.

Good luck! 

[ryan0]

I've pretty much totally redesigned the cutter,I just based it on that one.The designs will be pretty fast and stable as hell.I've saved loads of weight by using a laser instead of a dremel,and the construction will be very sturdy and durable.If this works out at all,then I'll build a cnc mill with a dremel motor and spindle and heavy duty stepper motors.I am determined to prove you wrong alien 

[PhenomenalDesigns]

You can get stepper motors from most broken printers, well mainly those big office ones, usually when they brake, its not the motor, so head to a junkyard or something and see if you can salvage one

[Alien_X]

Hehe, yeah, prove me wrong!

To get the speed fast, you need:

A decent motor - alot of holding torque (IE. not scrapped from a printer)

A decent leadscrew + transmission nut - IE. not allthread if you want top speeds, although it is a trade off of speed VS rigidity and whip.
To get maximum speed you need a proper lead-screw and a delrin drive nut that is preferably anti-backlash. So you would need a trapezoidal screw since you live in the EU.

And saving space and weight with the laser is good, as long as it works good, which it should for light engraving work.
You could always use a dremel flexishaft as a spindle, although they have a fair amount of runout.

I also wouldn't recommend coupling the motor to the shaft like he has done.

Anyway, 'nuff negatives.

Using chrome bar, perspex and fibreglass will make it alot stronger and alot better.
What software are you planning on using for the control?
Where did you get your driver from?
What ratings are your motors?

[ryan0]

the software used to drive it is the mach 3 software for the mach 3 stepper motor controller
don't know the ratings of the motors :L

[802Chives]

1W laser diode..............very interesting, I use laser diodes everyday so I know a little about driving them. 

Do you have focusing provisions? As the raw output of a Laser diode wont cut squat, you need to colimate/focus the light to concentrate the energy. 

What are you using for a Laser diode supply, is it a complete setup or are you going to have to power it urself?

Are you able to cut stuff with the laser already?

I have to throw out a warning with that diode, it will burn hole in you head if you point it in your eye.  Be very careful because by the time you feel pain in you eye with one of those things it is already too late 100X over.  There is a video of a rabbit being hit in the eye by a laser and it will turn you stomach if you watch it, but you will respect the laser that much more.

[robin1989]

OMG CHIVES i just got a wicked image of you at work it was like omg lol

[ryan0]

Hey guys just though I'd update you guys,
I've decided to use a dremel instead of a laser.
Atm I have the X and Y tables built,just need to get the rest of the stand and the z axis fixed up,then assemble it all!