Homebrew CNC Gantry Painter

[tachus42]

I used to a printer tech so I've got a few thoughts.
Don't try and angle your nozzles to try and hit the same spot. The dot shape from each nozzle will be differrent and one color will bleed out from under another. For example a green dot made from cyan and yellow will be cyan on one side green and the middle and green on the other. Space the nozzles apart a interger number of pixles apart and handle the offset in software.

You might want to check out Ghostscript, www.ghostscript.com its a open source postscript interperter (RIP) which as well as all the standard printer drivers can also output simple bit map files with the required pixel on/off type of format.

[vacpress]

tachus-good point - the angle affecting dot shape. i am probably not going to build anything like that 4 color printhead. i am allready looking at a system that will allow much smaller amounts of paint to be delivered to much smaller spaces. possible a thin plastic or metal 3" ring being driven through a pool of paint, and past some very small nozzles. with 3-4 nozzles, i can make much smaller circles.

if i try to use HP RTL, how do i take the info from a generic driver and store it, and then print it? can i emualte all that in software?

i am a fairhand at "PicBasic" style microcontroller programming..

for now i am going to just build the roving gantry, as i have all the parts on my table.. just gotta take the time to do it right or it will go in circles! any slop in build on this guy will show after a foot or so of movement.

[tachus42]

Vac, Just saw from you post in another thread that you are already looking a ghostscript, here is a link which might be helpfull if you havn't aready found something similar http://www.ghostscript.com/doc/gnu/7...s.htm#Uniprint
It looks like you could make a custom upp file and have it output a sun raster file which could then have the head movement commands spliced into it by a simple script.

[vacpress]

tachus- yes i am discussing this with someone in anothe thread - the script would read the raster iamge pixel by pixel, line by ine, and move the printhead to these locations.. any elaboration on this script would be lovely

what is this process called? where can i find an example? who else has done this? how hard is it?

the uniprint document looks very promising. one question.. if i define all theis information for the machine in this driver, what actually takes the pixel\colro data, and gets the mechanical system to spit it out? i like how you can set offsets between print nozzles with unidriver.. thats something we will need.....
i am gonna start building the gantry in a few hours. I may try my "chepa linear bearing" idea since i have really never used my lathe for much other than making model components, and making motor couplers. printing the templates out of solidworks is so obnoxious when it takes 3 pages of 81/2x11 all cutup nd taped together.

[kcoaks]

Vac, you mentioned using PIC basic...have you settled on a particular PIC? Just curious. I'd lend a hand with the PIC code, but my experience is strictly PIC assembly, and probably more limited than yours. But I'd be happy to lend a coding hand, if need be.

I know people keep saying this, but those drawings are incredible! You're pretty handy with the 3D.

[vacpress]

kcoaks- ive used PBP to make robots and stuff with PIC16f84A s


and the drawings: thanks! i love compliments, as its something I hav tried very hard to get good at..

[turmite]

Vacpress I can see already this adoption thing I proposed is not gonna work! These folks are not gonna let you go.

I have a couple of commets and only hope to help what little I can on this open source thing.

1. It looks to me that the paint guns you have drawn are in reality jamb guns or touch-up guns instead of airbrushes.

2. While thinking about your project I envisioned a huge, yet lightweight frame that could be mounted vertically and programmed with the layout of the front of a house and viola or whatever that word is.....a cnc house painting machine.

I agree with everyone else here that for a young person that has tons of talent you also seem to have a bigger heart.

Mike

[vacpress]

<smile>
i think im just an MIT wannabe... im in art school. it somtimes leaves me craving math..

the paintguns are in fact "detail" guns, or touch up guns. on the package it said "detial airgun for..." in some bad asian translation...

I am going to move to something much more like pixation is doing when i move from a pen for testing upto a "printhead" i am actually about to go walk into the shop to start building this, after i print a few cut templates out of solidworks. sucks, i dont have a bandsaw here. im gonna try and do it with a scroll saw, if that dosent workout, i am just going to machine some motor couplers and maybe give the v-bearing idea a shot. (see holy grail thread).

its odd so many of the "gurus" here have remained silent on this. i was hoping for some really rigorus criticism and saugestions..


thanks for the input so far though! i will photograph and post my evenings progress. i only hve like 3 or 4 hours before i gotta go see my girlfriend.. darn.

[ynneb]

I am so jealous. If only I could draw like Vac in Solidworks.

Keep those concepts rolling in, its soooo inspiring.

I still want to see a CD coater launcher design from you Mr Vac.
That neighbours cat would make a great target.

[vacpress]

I am currently building a 1/2 scale model of foamcore and balsa, since i have decided to wait and use a bandsaw to do the main body cuts isntead of my crappy scrollsaw. Heres the first picture of several i have prepared this evening.

I also posted about 15 messages in various yahoo groups looking for a programmer to help me with the "raster to step\dir" problem.


http://www.interinar.com/BSD-01.htm @$26 this driver may work great for the 3 steppers that need microstepping.

[vacpress]

solidworks is easy to learn if your a graphics freak like i am.. the first time i used it was like a revelation - something like the first time i played with legos...

to really learn solidworks takes a year though.. my first projects didnt look like this.. if anyones really curious, i can start a thread "the 2 year development of solidworks mastery" or something.. show some images from my first projects... its inspirational for me at least to see people go from suck - to success..

[publitime]

vac

I think HyperXpress will be intressting to RIP an image and thene import it into a CAD program.