Mega Prusa i3 3D Printer

[Brian_Krassenstein]

Aldric Negrier, a Portuguese designer and 3D printing guru, says you can build an enormous version of the Prusa i3 Printer for around €300 euros, or $320 USD. Negrier wrote an Instructable post for the project which includes all the necessary design files, a complete bill of materials, and some very helpful tips on building and finishing what he calls the Mega Prusa i3 Rework. Negrier is also the inventor of the BuildersBot, and he's written a post which will help you build one of those as well. You can read the whole story here: http://3dprint.com/50680/enormous-prusa-3d-printer/


Below is a look at the design for the Mega Prusa i3:

[curious aardvark]

40x40x40 cm for 300 euros !

Now that's bloody impressive.

[richardphat]

He did not tell everything. That's just for the raw material, cheap ass quality ramp. He did not mention the price for the laser cutting/milling service, which could explode the price. The bolts and nuts are metrics stuff, and US/Canada are not a big fan of metric.
Certainly they do have somewhere in our country, but it is just a pain, when home depot/Rona/Reno don't have what you're looking at. Surely you can improvise and replace those metric to imperial stuff, but then, there are couple of components that jsut work with metric.

On top of that, the shipping cost from europe to America, would add another 100-200$

He also used tools which most craftsman and hobby do own, average people like me just don't have the space or appropriate environment to own the tools. Even if you do not account for the tools... it will cost to an equivalent of 1000$ invested in time/materials.

Well, I had my high hopes....

[bernarddt]

Hurray! Somebody that don't think the world revolves around America's "feet and thumbs"! Because they are all different sizes!

I'm going to try hard to build one of these!

I was so disappointed that the "pre-build" commercial stuff for home use really only print like 15cm^3. And they are very expensive (R16k to start with). Then I found the Prusa i3 kits with 20cm^3 print area for R6k (ZAR). I then started realising that I can build one from locally sourced parts myself. Relieved by the larger print area, I wondered if it would not be easy to just scale everything up to build one bigger? Then finally finding this! 4x the build surface! 40cm! That is wow!

I realised that the quality of these home grown printers may not be so good as the others. But if you print larger stuff the rough quality becomes less noticeable than on small things. I'm looking to print pot-plant buckets and holders. And other larger replacement parts and containers and holders.

When you build something DIY, you normally assume it is excluding your time, that is very common sense. And because you are doing it as a side project at your own pace, the experience is worth your time.

I believe that the laser cutting is going to cost you a lot, but in South Africa it is not that expensive. Especially if you bring your own designs. Also Aluminium is not that cheap. But I'm willing to invest arround R6000.00 (ZAR).

I also noticed that the "Prusa i3 Rework" design allow for CNC cutting with an attachable Rotary drill flex cord. That is also very cool! I'm more worried about the electronics that is required, they are normally very expensive to get in small quantities and I don't know where to get it yet. Especially since it look like custom boards for the Stepper Controllers.

[richardphat]

If you will spend time building this, make sure you build some sort of enclosure. Printing something big in ABS easily cracked since temperature gradient is strong, even PLA would start having warping if you plan to print big pot size.

[bernarddt]

If you will spend time building this, make sure you build some sort of enclosure. Printing something big in ABS easily cracked since temperature gradient is strong, even PLA would start having warping if you plan to print big pot size.

Thanks Richard! This is very serious advice. I can just think that printing a surface of 20x20cm will have more reduction in temperature by the time the second pass comes over, so that the plastic would have cooled to much to bond. Now just imagine 40x40cm... 4x the roundtrip time!

Now I realise why the printers are so small. And that commercial ones are even smaller, because they want very good results, so they can't afford a warped print just because there end-users are normally less technical. If a RepRap printer warps, the end-user would just blame himself for doing something wrong.

Do you think that only an enclosure would be enough? So that the heated bed would produce enough heat to keep the inside temperatures warm. Or would one need extra heat?

Does someone also know if the heated bed stays on the whole time, or only during the first pass...

My mind is just going crazy... so with any 3D printer, does the firmware make provision for when it prints something smaller and each pass is quickly followed, to reduce the printing temperature, and when printing something large, that the printing temperature is higher. This will be a layer by layer thing to calculate as printed objects can reduce or enlarge in size. You can also print faster and slower, but the printer head can have a "to low" upper speed to be able to keep up. Or it can produce non matching layers if each is printed at different speeds...

[richardphat]

Thanks Richard! This is very serious advice. I can just think that printing a surface of 20x20cm will have more reduction in temperature by the time the second pass comes over, so that the plastic would have cooled to much to bond. Now just imagine 40x40cm... 4x the roundtrip time!

Now I realise why the printers are so small. And that commercial ones are even smaller, because they want very good results, so they can't afford a warped print just because there end-users are normally less technical. If a RepRap printer warps, the end-user would just blame himself for doing something wrong.

Do you think that only an enclosure would be enough? So that the heated bed would produce enough heat to keep the inside temperatures warm. Or would one need extra heat?

Does someone also know if the heated bed stays on the whole time, or only during the first pass...

My mind is just going crazy... so with any 3D printer, does the firmware make provision for when it prints something smaller and each pass is quickly followed, to reduce the printing temperature, and when printing something large, that the printing temperature is higher. This will be a layer by layer thing to calculate as printed objects can reduce or enlarge in size. You can also print faster and slower, but the printer head can have a "to low" upper speed to be able to keep up. Or it can produce non matching layers if each is printed at different speeds...

Enclosure typically gets the job done, you dont want colder air around your print. Mind you we put our printers in a 15C room, because the guy told us it's usually hot and the prints ends up cracking everywhere.

If you want to go a step further, incandescant lamp/reptile lamp (yes those lamps) are probably the most efficient bastard (typically 95% heat production over light). They heat so much in small enclosure which can guarentee easily an inside temperature of 40+C, extremely ideal for ABS, Nylon and other warping filament. Just shut the lamp down when you print PLA

It is a poor man version of what industrial printer featured, but does an excellent job.

[bernarddt]

Thanks for the advice. We normally have hot temperatures in our home office. So I will test and see what work.

My next step is figuring out how to het the RAMPS board. We do have PCB factories. I'm just worried that they only mass produce.

[bcrazycramer]

I'm actually thinking about building this Mega Prusa i3 Printer as well. I'm just worried that there isn't a place to throw out questions along the way if I get stuck. It doesn't seem all that complicated besides getting the acrylic pieces cut.

[bernarddt]

I think you should try. I will not be to worried. You will most likely get someone that will respond to your questions if you post them here or in a new thread.

Ive been reading up on RAMPS board that seems like something I will also need a specialist shop to manufacture. With surface mounted components and double sided tracts

But the more I read up on the RepRaps the more I'm impressed by their ability to completely self replicate...