Introduction

Who and Why

My name is Rui Caldas and I'm a teacher at ESAD College of Art and Design and i'm building a 3D printer.

Some courses like multimedia and product design have been using 3D printing for the last year and the tool already prove to be very useful to prototype and build models or real parts.
But there is a problem: the printer's size.
For interior and fashion design, for example, large scale printing is mandatory. Architectural models, normally are bigger than 20 or 30cm, and in fashion or product design, real size is the needed size.

bq Prusa i3 with modifications

Today, we have the bq Prusa i3. This low end printer is being tested and already prove to be not so low end. The problem is rigidity. After some modifications and improvements in it's structure and firmware, the printer went from mid quality to a completely different level. For example, I was able to push the limits and print layers with 20 microns, keep a good surface finish. Some printers in the market at five times the price, have 50 microns as best settings.
Modifying the Prusa i3 was easy, but soon we reach a point where the energy spent to modify it was to high, facing the gains, and we soon reach to a point where is preferable to build one printer from scratch, than trying to add more stuff to the other, and solve the size problem the right way.
So Prusa i3 is now in it's final form, and ready to bread the next one.

The new printer

Render from the first 3d sketch

for budget purpose.

Credits: 3d printed Prosthetic Arm

in picture from thingiverse

thing:770556 by LTech.

Solving the size problem means having the biggest printing bed possible inside the printers body. This exclude the delta type instantly. Trying to make a bigger Prusa it is not also the best solution, because it needs the double of space to work on the Y axis, as the entire bed moves back and forward.
My design uses the most eficiente size/space construction. The Z axis works in the printing bed, and the X and Y axis work in the extruder nozzle.
With this, just a little space is lost for the electronics, mechanics and motors, and most of the interior space is usable space.
The printer's main structure will have 1m by 72cm (to pass doors) with 1m high. The printing size will be something close to x80 y60 z80 cm; this is more than 53% of usable volume. So you can compare, the Prusa has a relation of 10.72%.
I'm using the repetier firmware on Prusa, and it proven to be much more eficient than the original Marlin Hephestos, so the big one, probably will use the same, configured for the bigger size.

The tools and components

The project is being made in onshape.com. It's a online freemium 3d parametric cad system.
The structure will use openbuilds components and the electronics based on the RAMPS 1.4 and some custom build circuits.
Other details will be explained later on other posts.

The next chapter

I will try to keep the blog updated as i'm building the printer, encounter problems and finding solutions.
Next posts will be about the construction, with detail pictures and some descriptions.

I also publish some other related stuff on Intagram, so fell free to follow.