is this build too ridiculous?
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So we're looking at building a large format printer- 3 foot by 2 foot by 12-18". The budget is pretty decent sized since its for work. we partly need a larger prints and party just for the hell of it and learning.
I'm building the frame from Vention extrusion. I'll have an x and y carriage that rides on linear rails and uses ball screws for the drive. The z will move up and down with a cast aluminum plate carriage/table and guide rods etc.
I planned on nema23 motors from automation direct.
this one for Z due to the weight of the table-25 pounds roughly. https://www.automationdirect.com/adc/shopping/catalog/motion_control/stepper_systems/dual_shaft_and_encoder_stepper_motors/stp-mtr-23079dThis would be for x and y https://www.automationdirect.com/adc/shopping/catalog/motion_control/stepper_systems/single_shaft_stepper_motors/stp-mtr-23055
my concern is that the duet2 can power them first. second is that with a ball screw and how freely they spin can the z motor hold the build platform up. I've thought about long springs on the guide rods or a counter balance system just in case it needs some help.
table would be heated and I planned on the lulzbot dual print head hopefully- we need dual heads and that seemed to be the most complete, ready to go setup there is. BLtouch and material sensors etc.
we have a lot of experience at my work with programming and building robotics and automated assembly fixtures. we do a good amount of 3d printing already so we have a good grasp on that as well. -
Two random thoughts
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Will the x/y lead screws allow you to move the head fast enough?
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You will probably use z sensor and bed level meshing/compensation so a perfectly flat ( and heavy) bed is not necessary.
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If this is for work, have you considered to purchase a printer?
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@zapta said in is this build too ridiculous?:
Will the x/y lead screws allow you to move the head fast enough?
see (unfortunately in german)
https://www.thingiverse.com/thing:2929869
he uses ball screws for x and y and says he achieves 100mm/sec on y with 12v
the speed will depend on the lead of the ball screw.the stepper motors should be fine.
see
https://duet3d.dozuki.com/Wiki/Choosing_and_connecting_stepper_motorsDuet 2 WiFi and Duet 2 Ethernet (maximum motor current 2.4A) => Stepper motor rated current <= 3.0A
if the weight of the table is too much for the motor you can try a geared stepper motor like
https://www.omc-stepperonline.com/economy-planetary-gearbox/nema-23-stepper-motor-bipolar-l76mm-w-gear-raio-41-planetary-gearbox-23hs30-2804s-pg4.html
or if that is not enough
https://www.omc-stepperonline.com/economy-planetary-gearbox/nema-23-stepper-motor-bipolar-l76mm-w-gear-raio-151-planetary-gearbox-23hs30-2804s-pg15.html -
also there is the duet3 that should be out sometime this year.
the driver of those will support at least 4A (and maybe even more depending on the actual setup) -
@zapta They have a 5mm pitch which is pretty fast- faster then the normal acme m8 screws that are used.
I've removed as much material as possible while still keeping it rigid- it's just a big table so weight comes with it- plus we already have a large sheet of milled cast aluminum.
we've looked at large format printers- they're expensive- specially for how much it would get used. The stratasys machine that is big enough is 180K. we're trying to stay under 5K because we won't need a business case and can just order parts here and there. -
@veti said in is this build too ridiculous?:
Looks like they had early production samples a few months ago- so hopefully soon. that would definitely open my options up for bigger motors/ enough power
I use nema23 stepper motors here for testing products and they get going fast very quickly. I'd thin speed shouldn't be an issue
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not quite the size you need, but i assume you had a look at the
https://folgertech.com/collections/3d-printer-full-kits/products/folger-tech-ft-6-3d-printer-kit -
or not quite the 5k (6k)
http://www.modix3d.com/tech-spec/?affcode=aniw
120X build volume – 1200 X 610 X 610 mm -
@veti this is a good option but by the time its all said in done with options and shipping it's over 8K. which makes it so we have to have a business case and ROI vs under 5k we can just piece it together with any leftover monthly budget. it also takes away from building one myself which is half the fun.
i'll definitely look into it more though. -
@kaduhn1 said in is this build too ridiculous?:
it also takes away from building one myself which is half the fun.
yes of course. and getting paid to do it is a bonus.
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@kaduhn1 is there no cheaper z motor without an encoder? Unless you're planning someting fancy its only contribution to the system will be a tiny amount of inertia.
Edit: Scrub that comment. Encoder ready, not encoder fitted.
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Have you considered a large delta? I built a 600 dia (24") by 620 Z for about $1100 that produces EXCELLENT results. One of the advantages of delta for large printers is that the "table" does not move. This becomes a HUGE advantage as printers scale (<=pun intended).
I'm using a 24" glass table for a bed. $40 on Amazon (US). 6mm thick. Custom Keenovo heater stuck to the bottom (about $200 to have custom made).
You said 2 feet by 3 feet by 1 to 1.5 feet. How about 3 feet dia by 3.5 Z? That would be slightly larger than my printer... I chose a lot of my scaling by choosing 1 meter HWIN Clone slides. That was an arbitrary decision. 3 or 4 feet diameter, and a little more proportional Z, should be easily achievable with 2 meter slides (and appropriate frame size).
Yeah, it freaks people out that they are tall. As long as you are not trying to run a large farm that has multi-level shelving, or have some other ceiling constraint... if not, then so what?
Anyway, if you want to think about this at all, play with this calculator. Here's and example set for 3' diameter, and 3"4" Z:
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That heavy bed system may require something special to prevent it from dropping when power is cut (as well as some help lifting it in the first place). I used a Rino 30:1 worm drive to lift the bed with belts in my corexy machine, but it could easily be applied to lead screw drive, too. The worm gear prevents bed motion when the motor is powered off, which means it should be possible to resume a print after power failure, etc. The Rino has an integral NEMA-23 motor that's easily driven by a Duet board and very high quality gears.
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You can get nema 23 motors in low current version, they are rated 1.8A but must be powered with at least 24v PSU
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Instead of moving a large bed up and down, what about a Voron2 style XY gantry that lifts in Z. If I was going to do a printer that size, that's what I would do. http://vorondesign.com/voron2.1
For anything larger I'd probably do an X axis gantry that moved in Y and Z with stationary bed. Like a gantry crane.
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@mrehorstdmd definitely saved that page- probably a good idea regardless. thanks
