DIYAudio CNC Router

[faustian bargin]

Originally posted by pinkmouse


Your best bet would be a vacuum table. If you build a chamber below the bed and then have a set up program that uses a 1mm drill bit to run holes every 10mm or so, then all you need to do is connect a high power domestic or industrial vacuum to the plenium chamber to suck the air out. This is how some industrial cnc machines work.

....

sounds like a reverse air-hockey table. if you can find an old air-hockey game on ebay or something, you're probably halfway there...

[pinkmouse]

Originally posted by faustian bargin



sounds like a reverse air-hockey table. if you can find an old air-hockey game on ebay or something, you're probably halfway there...

Good thinking, "out of the box", as those management consultants like to say!

But don't they mostly have perforated metal as the pitch?

[faustian bargin]

i don't know the answer to that one. i haven't played air hockey in a long time...i would guess some are wood (mdf or masonite) and some are metal.

...

'out of the box' is not difficult when you've never actually been 'in the box' to begin with. i'm an architect, not a speaker builder, nor machinist, nor electrical engineer...wacky ideas (most of them unfeasible) are about all i have.

[Variac]

Hee hee, I'm an architect in SF also, and your philosophy is the same way I justify my presence here on DIY. Sometimes we get lucky with the wacky ideas.I think most air hockey tables are made from MDF with a melamine coating. It can be bought with this layer on it. I'd be more interested in making an air hockey table with the cnc machine than vice versa. I considered making my own table when I discovered the Melamine MDF, but then calculated the number of (hand drilled?)holes...............

[ebrewste]

An interesting link on diy mills/lathes:

http://www.dakeng.com/index.html

[tom1356]

I'm up for this project If you decide to go ahead.

I just bought one of these CNC mini mills for PC boards etc.
Anyone else have one or know where I can get more info on using it? It's my first CNC and I'm not 100% sure on how to start.
I'm dreaming of being able to make double sided PCB's with .9999 fine silver traces.

http://www.minitoolinc.com/microdrillingandpunching.htm

[purplepeople]

Apparently, the slowing US dollar means my Canadian 2 cents is worth more today than when I last posted...

2-1/2 axis means that the Z-axis only goes up or down, but does not provide variable altitude. Full 3-axis can also position the Z-axis at specified points.

Anyway...for ideas try some of the actual manufacturers:

http://www.camtech.ca/home.htm
http://www.cheapcnc.com
http://www.deskproto.com/links/cncmachines.htm

Note that deskproto is a CAM software mfg company.

There are others. I checked my files and my google search terms were "cheap cnc".

I don't know what is in Europe, but Oriental Motor makes well-known and excellent steppers. Also check out a technique called micro-stepping which can increase your travel speeds and your accuracy for a bit of added control complexity.

If you can get an old pen plotter like an HP 7475 or something similar, then you can rip out the controller boards and use it direct out of a CAD program. Of course, you'd have to calculate your own tool paths, but that is a really fast and cheap way to get a controller. Also, you might have to scale it up at the cost of some accuracy, but if you are not doing particularly complicated cuts, then it might be just right.

:)ensen

[Rarkov]

for all your all your suggestions...

purplepeople:
That CheapCNC looks SOOO easy to make and also answers a few questions. I am going to design my CNC machine around this! I am just modelling it up now...


Thanks again!
Gaz

[emorysmith]

We built a similar machine using parts bought on eBay for under $400 including the 3 channel stepper driver which is driven from the parallel port of a Pentium 166.

Search on eBay for:

Steppers: "NEMA 23", "NEMA 34"
6-12volts, 1.8 deg/step or smaller.
Six or eight wire motors are required, unipolar motors won't work with the driver board we used.

Driver: "Stepper Driver" "Stepper 3"
The Stepper 3 is what we used. $99.00

"Lead screw", "Ball screw"
"Linear bearing", "Linear rail"

I don't remember the software used but it's DOS based and understands G-Code.

Email me if more info needed,
Emory

[emorysmith]

Me, again.
Speaker cabinets, I presume?
You might want to look at NEMA 56 motors
instead of the 23s and 34s I mentioned.

They will handle the heavy plywood, particle board and MDF you'll likely be using. Our machine was built for small routing and engraving jobs. We use NEMA 23s.
E