Build I3 prusa 300x300x300

Hi,

I'm starting this discuission because I'm looking for a new build project, a cartesian machine with big print area (300x300x300), I would like to use v-slot 2020 or 3030 for the frame and possibible v wheels for motion. I want to use electronic and other parts from an olter machine.

I search in openbuilds and in this forum to get some ideas but not have something really fun to build. I want some help to get good project with these characteristics, the idea get one prusa with creality CR10 style but build my me.

Also I'm open to other kind of projects with build area like a corexy but I'm intent to keep low budget project.

Thanks

For a bed that large, you're better of building a machine in which the bed will move in Z, not Y. There are two main problems with the i3 architecture. The moving mass of a large bed is very high and trying to control it at print speeds can be a problem. The other problem is the footprint of the machine starts getting too big. If the bed moves in Y, the footprint has to be at least 2x the length of the bed x the width of the bed.

For a bed that large I would recommend either a corexy or other cartesian type mechanism. Also, if you ever plan to print ABS, design the machine for enclosure right from the start, and use an adequately powered bed heater. 900 cm^2 of bed needs 500W or more to heat up to 100C for printing ABS in a reasonable amount of time. Consider using a line powered heater. If you're are going to stay with low temperature materials like PLA, you can get away with lower heater power.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Yes I understand your point but there a lot of printers very sucessful in the market with that build volume, creality and tevo tornado is one of that sample. And would like to investigate if there is a project simalar to that project. CoreXY is reallly a good option but is much more complicated to build and I not found any project that I really like Hypercube and D-Bot have many failure points.

I built an i3 type machine with a 300x300 mm bed (SoM), and ended up putting in a ball screw and DSP driver in the Y axis because of the problems in controlling the bed at print speed. Mechanical resonances prevent it from moving >40 mm/sec. It has been producing quality prints almost daily for over 3 years at the Milwaukee Makerspace with very little down time, but I would not do it that way again.

I also built a coreXY machine (UMMD) with a 300x300 bed. It works much better and prints much faster. I'll soon be updating SoM with a new bed similar to that in UMMD.

Both designs are linked in my sig, below. Take a look at both designs and see if there isn't something there you can use.

I suggest you think about what you want in a printer, look at a lot of designs, then design and build your own, taking the best stuff from other designs, or creating your own. Be harshly critical of the designs you look at. Think about how things behave under nonideal - i.e. realistic- conditions. It's much more interesting than following someone else's BOM and far more educational. There are about 1000 problems to solve in each design and build and coming up with solutions to those problems is where all the fun and education lie. If you follow someone else's BOM you may as well just buy a kit and save yourself the trouble of sourcing the parts.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

TDD is right, tossing the print bed back and forth in the Y axis is pretty iffy and creates a bigger trade off in print speed vs print quality. A moving bed in Z is effectively stationary during the print and will not affect print quality unless you decide to use software z compensation, then you might end up with extra vibration from the bed moving up and down during the layer.

The cr-10, tornado... etc. that have been "successful in the market" have not been successful because they are the best printers, it has been because they are cheap. An I3 style design is cheap to create, that's why it's been successful. And that's about where the advantages end. More moving mass, generally flimsier, moves the print around on the Y axis while printing, takes up more space.... the list goes on. CoreXY printers are a bit more complex I guess, but not by much. And I certainly wouldn't say they are more complex to the point they have significantly more failure points.

I would avoid the hypercube though, aside from the way the X axis is setup, having watched a good chunk of his build logs it's clear that he is an electrical (?) not mechanical engineer. That and he has made a lot of compromises in order to "use as much as possible from his old i3 kit" which is absolutely stupid considering the amount of extra and new parts he's bought or changed. Not trying to bash the guy, but his design seems to have become something he dived straight into and then put bandaids over what didn't work, rather than a fully thought out from the beginning design.

There are other configurations as well, basic cartesians like the makerbots, crossed gantry systems like the ultimaker and I'm sure there's more if you have a look. I have a chinese i3 and an old solidoodle 2. The chinese one works fine, prints fine and the kit was overall of good quality (it was from a legitimate company that comes from the 2D printer market), but I would prefer the solidoodle 2 despite the fact it has many more questionable design choices than the chinese I3. It is more compact (not just because it has a slightly smaller print bed) and once I level the bed and align everything, it stays aligned because a box shaped printer is much more rigid than an I3. With the I3, I never know where to pick it up from and I always feel like where the gantry meets the bed assembly it will twist, bend or break.

Quote
the_digital_dentist
I built an i3 type machine with a 300x300 mm bed (SoM), and ended up putting in a ball screw and DSP driver in the Y axis because of the problems in controlling the bed at print speed. Mechanical resonances prevent it from moving >40 mm/sec. It has been producing quality prints almost daily for over 3 years at the Milwaukee Makerspace with very little down time, but I would not do it that way again.

I also built a coreXY machine (UMMD) with a 300x300 bed. It works much better and prints much faster. I'll soon be updating SoM with a new bed similar to that in UMMD.

Both designs are linked in my sig, below. Take a look at both designs and see if there isn't something there you can use.

I suggest you think about what you want in a printer, look at a lot of designs, then design and build your own, taking the best stuff from other designs, or creating your own. Be harshly critical of the designs you look at. Think about how things behave under nonideal - i.e. realistic- conditions. It's much more interesting than following someone else's BOM and far more educational. There are about 1000 problems to solve in each design and build and coming up with solutions to those problems is where all the fun and education lie. If you follow someone else's BOM you may as well just buy a kit and save yourself the trouble of sourcing the parts.

Thanks for your reply I've read all your post in instructables and It was amazing I've forgot the build of a cartisian machine with a big build plate. I've already build 2 other printer and itopie (MDF frame) I know not good and that is the printer that I want to disasembly to build another one with best specs. I'll follow yout tips I've love the design of VORON corexy excluded the fact of axis X and Y are using smooth rods of 8mm. However Z axis I think is good lead screew one or each side and the guide system is two rods for each side. I'll maybe use this ideia but syncronize leads screew I'll use a belt and just one motor to move bed up and down just like you refer in or post, and for guides maybe I'll use 2 rods of 12mm for each side, for X and Y axis I should use linear rails instated of rods.

Just for finish you're saying that in a 3d printer moving parts should be strong enough to be impossible any child to unscrew or unbalance the bed etc, however in some delta printers design it's usually to magnetic rods to connect effector do you disagre with that?

I'd say that if there are kids (or cats) in the house and you use magnetic balls to hold the effector on, you'd better enclose the machine. I have no idea about performance of those machines, whether the balls allow anything to displace while printing. I don't know if I would build one that way. I haven't studied the options.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

The Prusa i3 Mk 3 design is excellent!

250x210x210 there are 300x300x300 out there

Josef Prusa and team have put a lot of engineering into the design
Hardware, firmware, software

Prusa firmware is out on github -- so I think it is open source

There are a lot of people out there to support the Prusa model

If you like to Build please check out the 300 X 300 X 300 Printer I designed from scratch, It is a cabinet type Cartesian printer. I have complete plans, templates parts list and the STL's available for download on Pinshape Use the keyword G3DBuilder
If you have a smaller printer you can print all the STL's for the larger printer. I have been using this printer for several months now and am extremely pleased with the speed and quality.

Many thanks for the help, I've decided for now following the hypercube of tech2c using 2020 slot with some mods to increase Z length and build plate to 250x250. For now I'll use the heated bed of my prusa 200x200 but it will be possible to increase to 250x250. This project have a lot of remixs solutions using larger rods, using closed belt circuit in Z instead of connect the motor to the leadscrew etc.