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View Full Version : Cnc cad program and hardware opinions requested



science_geek
06-12-2009, 04:45 PM
I have built a cnc mill that I am currently using a BS2 to controll. I was working on making it run with a Parallax Propellor chip with a 4d system uoled-32028-pmd3t display. I have been working on making a simple cad program that would cut a piece after it has been drawn. I was gaining much success in getting a simple cad program to work when I accidently fried the display. (Yes I cried!) In my search for a new display I decided to get a bigger display about 7" diagonal (like this one . My cousin further pushed me in the larger display selection cause he wants me to market this mill locally. (I dont think it will sell but what the hey...mite as well get some experience in doing some things professional) One What to use as a micro processor or microcontroller. I have looked at the roboboard with a keen eye but wonder if its easier and/or worth it to jack up the price to use a complex board. Also, if i use the roboboard a vga display gets used, but I am more experienced with seriel displays and writing software to controll them. But if I use a vga display and a roboboard I could get a basic open source cad for something like windows ce and modify it to work with my cnc mill. But I have more experience with the parallax propellor so I could do more faster. I dont think i will ever sell one of these mill to anyone other than my uncle, but i might as well do it right the first time, the mill works great with a precision of 0.0000390625". Like i said, I want opinions and advice on where to go with the hardware and software of this project any info is better than no info.

jes1510
06-12-2009, 05:40 PM
What about a computer and EMC2?

ScuD
06-12-2009, 06:08 PM
A precision of 100µm? Do you mean that as in the repeatability of moving the axes unloaded or as in actual milling?

In what substrate?

I mean no offence but I would love to see a home built machine with that accuracy, do you have any pics?

If you're going for a large display you might want to offload the graphics from the actual cutting.
Something like a processor that drives the display (why not a propellor, you're used to working with them and as i understand they're pretty good in the graphics department), get another controller to handle the actual x-y-z movement and maybe a central processor to coordinate the rest.

Oh wait, prolly cheaper and easier to use a pc :)
Seriously, there's a lot of good software out there, if your mechanics are really this good you shouldn't put too much work in a custom designed pc when everythings out for grabs.

I've used turboCNC with good results on a really old (and i mean ancient) laptop.

science_geek
06-12-2009, 06:08 PM
I would like to avoid using computers, this mill has a theme or two.

Ultra portability.
100% deconstrable.

A computer would add bulk that im trying to avoid, also i have various sensors set up in my garage and a testing chamber that i want to still have the ability to wirelessly read and change settings like i can do with my prop and xbee.

i can get pics up later. i have graduation tonight so i cant fix this post much.

science_geek
06-14-2009, 12:39 PM
as promised pics are added, the accuraccy of the mill while milling styrofoam and wood is when its the precisest, the precision really depends on how fast im moving whne i am milling aluminum, because if i go to fast the bit wabbles a little but you cant tell if it has till its done and you look at the reflection of the light.

the table can move 24" in the xy direction and the dremel can move about 6" up and down. the stepper motors are 1.8 degree unipolar stepper motors running in bipolar mode. i am also running in 1/8 step mode. i actually cant measure the the amount one "tick" moves, but my math tells me.

as for the controller i was thinking the triblade prop setup seen on the paralllax forum, this wuld actually help with the other things i need it to do that i have planned