First steps in converting my 24" x24" x24" frame corexy into ... Megagentis ...

First steps in converting my 24" x24" x24" frame corexy into … Megagentis … Megathios… Megalien? Name still needs work. I will give more updates as I get further along. Name suggestions welcome.

This will be the forth iteration of this printer. I love that printers make more/new printers. But I will admit two printers makes the job much easier than a printer iterating itself. It leaves more flexibility for “Oops… Forgot about that” situations :slight_smile:

I wonder what the effective upper envelope limit is for FFF printing? Where smaller nozzles are impractical and bigger nozzles look ugly…

@Mike_Miller This one I am going to try dual extrusion again (big nozzle, small nozzle). But this time I will take into account height adjustment. Since I already have the printer enclosed it is a great ABS machine.

I plan to use it almost exclusively for making prototype foundry tooling before cutting the expensive billet tooling, so I need the size. Ductile Iron is a real animal. Heat stresses, shrink, mold tear-up, hot spots, misrun, you name it. If it can go wrong in castings… it likely will at least once.

So the prototype tool will let us look for those gotchas before you are in 10K+ into a production tool. Especially important is shrink factor since it is generally geometry dependent and non-radial (different in X/Y/Z).

I have done a few so far just for fun. But I think it will be a cool side business.

We have a 3’x2’x3’ FDM machine at work. Makes full scale bulldozer parts. Kinda fun. But has all the same issues we do except warp because the machine is a damn oven.

I’ve been considering building a “Reprap” that size just to piss with the RP manager who is always ripping on my “toys”.

@Joe_Spanier what size is the nozzle?

They have different sizes but all of them are standard Reprap sizes. The thing is literally a giant makerbot.

I ran into the “oops, forgot about that” over 9 months ago. I still haven’t recovered.
I plan on designing my next printer around that, by using mostly off the shelf parts.

“Gigagentistathios” :wink:

@Shauki yeah, but then you can switch to tera-, peta-, exa-… :wink:

Kilogentis? Next one megagentis, next one gigagentis, next one teragentis, etc… :smiley:

@Shauki Thanks. I am still fighting z-ribbing. I have to order a lower tooth count for my z stepper motor that results in integer steps to avoid the rounding errors. I noticed Jason does not have this z-ribbing issue on his. He is using a 20 tooth I believe.

But I am SUPER pleased with my x&y tolerances. This was printed at around 100mm/s. The only defect I find is around 100mm/s it begins to introduce very mild ringing around sharp corners that shows on vertical faces. But in simplify3D I can minimize this by turning down my exterior perimeter modifier but let the other perimeters fly.

That looks good… anywhere i can find the specs of the machine that printed that ?

I just checked. I had dropped max acceleration to 7000 mm/s2 when I started it up until the bushings smoothed out as I had chatter at 9000. Yes I have default at 4000mm/s2.

@Eclsnowman Does it have a Bowden tube extruder?

@SirGeekALot the new one will be hotswap hybrid mount. 5:1 nema 11 onboard. 5:1 nema 17 Bowden. I am working out the details of the setup now.

@Shauki single motor but I think I will use that new robodigg beefy nema 17, or maybe a nema 23. I like the simplicity of single motors… I just need the torque sized appropriately.

Wow, so how big do you think it will be able to print when it’s done?

@Eclsnowman interesting…is it a fair guess to assume your plan is to use the Bowden for a larger nozzle extruder for blasting in large amounts of infill or support material quickly?

@SirGeekALot I wouldn’t run them at the same time. Direct Drive for flexible filaments, Bowden for speed. Wiring would be modular so I change from the bowden and mount the nema 11 to the carriage. Then connect a modular wiring extender from where the airtripper usually connects to the harness.

@Shauki Less motors to fail, simplified wiring, and I just plain like it better. I guess on this one discussion we differ on our interpretation of simplicity. For me mechanics are simple, belts and pulleys easy to manage and trouble shoot. I like mechanical solutions over additional electronic ones.