The mammoth build

Mostly Printed CNC - MPCNC Your Builds
#1

Upon starting this project I set out to build a machine big enough to build tall dice Towers small furniture and large objects with walls only I have done it. it prints okay quality not pristine trying to post any helpful hints I found for making an oversized build to get that build area you’re trying to make stable

Trick number one attach top and bottom of frame to solid structure at as many points as possible IE house or garage you’re actually in built onto the actual garage or house

Tiptoe cross frame tension wires with turnbuckles remember once you get them on one way you have to have the other essentially making an x on a side of frame that you can secure to a solid object zip tie wires together and if at all possible put some type of dampener so they don’t act like Springs and cause you’re built to sway

Speed is not your friend when trying to produce a large build plan on going very very slow like 30% or lower

Tiptree upon deciding to build a large printer remember it has to have as much space above as below the top of the printer if your z-axis touches anything it will throw off your print

#2

Here is a picture of the mammoth build this is a 48 inch by 48 inch my 48-inch Cube build requires extra belts extra wires and a longer screw

#3

Pic

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#4

Whoa. Do you have any pics of what it’s built?

#5

Oh my goodness, does it work?

#6

Finished it last night this is our second machine from vicious printed out 3 test Cubes but limit of picture size preventing me from posting working on it will fix

Currently printing out pirate ship

#7

I figured out a way to make the Gantry telescoping with your current parts just reconfigured I plan on making an 8-foot tall I’ll let you know how that goes when I get to it will try to respond to this post as much as possible and let you know my updates but that’ll be after I build my other four machines

#8

Holy crap!

#9

8 feet tall? Won’t that take weeks to build anything? What size nozzle/filament are you using?

I saw one of those gigantic machines at the maker faire, and it used filament pellets, and it had a 3mm nozzle, so it was basically the machine that makes filament.

#10

How do you keep the Z axis from swinging like a pendulum?

#11

Hi Chance,

Very nice build, congrat’s!
I’m working on something similar right now (but a bit smaller).
What puzzles me right now is how to deal with the heat bed?
Do you have any solution you are using on this machine?

On mine, I will experiment those silicon heating pads, but I was wondering if you are maybe using a better solution?

Here is how mine looks like:

You can see the silicon pad. I’ve purchased this small one just for test purpose, my plan so far (if it works) will be to have 9 of hose, controlled by another arduino. But I’m not entirely decided yet since It may be complex and costly.

From my first tests of yesterday, rigidity should not me too much of an issue as long as you don’t use very high acceleration settings. But it is likely that rigidity will be important when it will come to actual printing, especially during the first layers, when the nozzle might have a tendancy to grind the previous layers during infills. On my printer I have about 400-500mm of travel, but in your case it is much higher so I would be a little more concerned.

#12

i like that build Dui, ni shuo de dui pendulum swing is stoped buytwo thinsg
slower movement and attaching bottem screw brace in pics below

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#13

had this part brake

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#14

so it printed like this

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#15

after some work this is printing this right now

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#16

Dui, ni shuo de dui for the bed problem get a pace of glass to print on i use mirrors because i find two dollars a pace spray heavy and i mean very very thick with very cheap hair spray let dry 30 mints works for PLA, TPEG, ninja flex and most others if you are working with ABS or abs blinds this will not work

and ideal temp for room is 69%F to 79%f

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#17

Going that tall you’d be better off lowering the bed on 4 corners as you print rather than have a humongous long gantry that you can’t keep still.

#18

Haha, the first print was horrible, but the second one looks pretty good actually!
I think you may want to consider putting your extruder motor somewhere else, ideally not on your Z axis. This way you’ll be able to print faster without too much wobble.
I also suggest you to use a bigger diameter nozzle, otherwise your big prints will take months to be finished. I use a 1.2mm on mine, it is way faster.
Last thing: Attaching your Z axis threaded rod may reduce the swing, but it will introduce some Z wobble if the rod is not perfectly flat (and there is a pretty good chance it is not.
If you see some weird stuff happening when you print taller things, this could be the reason.

For the print bed, I plan also to use a mirror, like you, since it is cheap and easy to find. But I would like to find a way to heat it, since on big parts warping will be a major issue and I’m pretty sure glue or spray will not be enough. It works ok for small parts around 10 x 10 cm, but bigger stuffs warps pretty bad without a heating bed, even with PLA