I am wanting to build a giant inkjet printer. I was thinking about taking a desktop printer and attaching it to an x and y axis scales up from the normal contrast ratio. I have heard of programs to scale up/down the resolution for you to print big pictures on 11x8.5 paper and you glue them together.this idea might could be used for a big printer. These huge printers are quite expensive and i want one without having a few thousand to spend. I would like to hear any ideas, criticisms, or alternatives.
How big do you want the printer to be?
you can make a robot moving freely around with one or more inkjet head.
X Y coordinates can be fetched from GPS or with the help of some indoor location system (how far am I from the 4 walls)
I am wanting a printer about 8' by 11.5'. I am also wanting the printer to stand up so i can print murals on the drywall. the programming of the inkjet head is too complex for me right now.
Google vertical plotters. They use two stepper motors to position a platen with a pen on a vertical surface. It would be challenging to adapt a print head, though.
Those print heads have to be a certain distance from the media to work. That means very straight guides over very flat walls that likely need to be coated with something that will take ink like paper.
I'd like to make a big one that could do 1cm to 2cm pointillism with paint. Much slower but good work takes time. 
Quite separately from any alignment problems I suspect you would have a problem using a standard inkjet print head on a large surface because the droplets stay the same (very small) size. It would be the same as printing enough A4 pages to cover the wall - about 144 for 8' x 11'
Have a close look at outdoor posters and you can see that the pixel size is actually very big. I don't think they have any more pixels than a regular photo.
I wonder would it be possible to make a printer that uses coloured markers (like an old HP plotter) in a pointillist fashion. The machine may have to wait for one colour to dry before doing the next colour to prevent contaminating the pens.
...R
Robin2:
I wonder would it be possible to make a printer that uses coloured markers (like an old HP plotter) in a pointillist fashion. The machine may have to wait for one colour to dry before doing the next colour to prevent contaminating the pens....R
Have you ever seen a Power Painter? They feed paint from the bucket through hoses to the rollers.
A sponge head servo-tapped might work.
GoForSmoke:
Have you ever seen a Power Painter? They feed paint from the bucket through hoses to the rollers.
A sponge head servo-tapped might work.
Very interesting.
There was an Arduino Thread about this polargraph idea a few months ago. I don't seem to have kept a link to the Thread. Maybe it would be a basis for the OP's requirement.
...R
LOL, get a barn wall, a servo controlled mounted paintgun and lots of different shade paintballs.
I researched this many years ago and I think it can be done
x and y are the minor problems as they can be run from standard printer software. The harder part is going to be the addition of a z axis that's fast enough to compensate for the distance between the print head and the wall. Cd players had a way of laser measuring the distance to the disk and adjusting the lenses to match which would work except a lens is tiny a complete print head including cartridges would be a beast to move at high speed.
the software thats used to tile a picture for printing can also hide line up markers in the print. These are single pixels that you could use to manually line up the rig for the next tile using lasers or cross hairs so its possible. Larger x and y runners are also possible to move the whole print rig including its own x and y axis would work.
cartridges can be refilled after ever tile reducing the weight of the rig or refilled by gravity feed from the bottles.
My plan was to make a unit that could print photo quality pictures to office wall as artificial windows.
I never could come up with a plan for the z axis that could move fast enough with out shaking the unit.
Now theres things like the arduino and micro stepper motors it may be possible
gpop1:
The harder part is going to be the addition of a z axis that's fast enough to compensate for the distance between the print head and the wall.
They call them "wheels".
Keeping a printhead close to a wall at a few cm/sec shouldn't be as hard if the distance sense and adjust is built into the head. Just check your printer for how close it will need to be.