Are multiple extruders the future of 3D printing?

I have heard mixed responses regarding multiple extruders. It seems a lot of people feel it isn't terribly useful. Others are all for it. Right now it seems it is used mostly for support materials rather then multiple colors. I even saw a commercial about support material filament for dual extrusion printers. The filament is water soluble which is pretty cool. So it seems there is a push more so in multiple materials, rather than multiple colors. I could be wrong this is just what I have seen. But, the other day I was thinking about how we are right in the middle of the beginnings of an explosion in the 3d printing field. I feel like right now we are almost in the black and white era of 3d printing. Imagine a multiple extruder printer that can print at a high resolution in not only detail but color also! Imagine the amount of quality and detail in designs that will be possible. The funny thing is we already have everything we need the push 3d printing forward dramatically. The advancement is correlated more so to our imagination than availabilty of components. After all, my printer is 8 BITS lol!
I believe the Star Trek tech list is not complete.
I was wondering what others forecast is on the future, both short and long term, of 3d printing.

I guess we still have to figure out the teleportation...

There are a few choices for multiple colours and materials:

- Multiple nozzles on one hot end. Can be made to work quite well with 2 nozzles if you control the temperature of the standby tool carefully. I have one of these.

- Multiple independent carriages on the X axis. There is a modification to the BigBox printer to support dual carriages. You can go beyond dual carriages, and use more than one X gantry if it helps e.g. 2 gantries with 2 carriages each.

- Mixing hot ends, such as the Diamond. You need to use firmware that supports simultaneous retraction of all filaments going into the hot end even when you are only using one or two of them. The mixing isn't perfect - the filament comes out rather like stripey toothpaste. There are some threads on active mixing (in the Development section of these forums AFAIR) to improve on this.

I think the future is mixing hot ends for multiple colours, plus a separate nozzle for support material.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

... it's pretty usefull, if you can change filament diameter, material or color "on the fly" to create objects with locally different properties

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

My guess is that colour printing will go to SLS printers. The top-down process is amenable to colouring with a relatively standard inkjet type print head after each layer is sintered. Unfortunately SLS isn't particularly DIY friendly.

I believe FDM in general is running into its inherent limitations. In fact, some believe 3d printing is on the peak of the hype cycle of emerging technologies. I'm inclined to believe that. As it is right now, FDM 3d printing is (super) useful to DIY enthusiasts and for rapid prototyping, but it won't ever become mainstream because of part quality limitations (strength, aesthetics, resolution).

Unless a new breakthrough technology is developed, I believe stereo lithography and SLS printers will become far more dominant in the future.

... I'm propagating DIY-SLS with fibercoupled high power laserdiodes since some 8 years now here in the RepRap-forums -- now should be time to start with seriously

Could be, majority is anxious, when handling with lasers and security measures ... but didn't get much of a feedback from the 10+ guys, that got a laser and/or drivers for them from me

Started a comercial development project for a new sort of "laser-assisted additive manufacturing process" (LAAMP or LAMP ) three years ago, which was cancelled for internal reasons

Now restarting again with my new company

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

I believe the next step in FDM printing could be smaller, closed loop extruders to overcome the problems of Bowden tube.
Maybe we need thinner filament to allow for really small extruders. ( We have made huge progress going from 3.0 to 1.75 filament, why stop here? )

Multiple nozzles on one carrier requires some tilt mechanism, otherwise it's a 1st. layer nightmare.

And beside all the mechanical problems, there are only a few people able to write the necessary slicer- and printer software. You have to convince them to support "your" new printer design...

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VDX
Now restarting again with my new company

Viel Glück damit, Victor!
...suchst du noch Mitarbeiter?

Edited 1 time(s). Last edit at 01/13/2017 03:41AM by o_lampe.

I think FDM nozzles can't go infinitely small. At some point you either can't extrude properly, or print so slow that it's useless for all intents and purposes. That's one of the inherent limitations I was talking about.

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anvoice
I think FDM nozzles can't go infinitely small. At some point you either can't extrude properly, or print so slow that it's useless for all intents and purposes. That's one of the inherent limitations I was talking about.

If that is a remark about my proposal to use thinner filament, I agree. Smaller nozzles are not helpful, but I meant e. g. 1.0mm diameter filament to size down extruder motors.

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o_lampe
If that is a remark about my proposal to use thinner filament, I agree. Smaller nozzles are not helpful, but I meant e. g. 1.0mm diameter filament to size down extruder motors.

I agree that could be helpful, less weight on extruder gantry is always nice.

Personally, I think there needs to be an alternative plastic-shaping technology to really make it mainstream. Right now, there are just too many things you can't make with even the best of FDM printers.

... with my developments for "additive wire-deposition" methodes I've got finest diameters with FDM/FFF of 0,1 mm -- or 0,01(!)mm with DLM (Direct-Laser-Melting) ... could even deposit platinum wires of 0,001mm (1 micron), but this is only feasible for IC/chip-level manufacturing, not for general AM (Additive Manufacturing).

Smallest detail size with (high viscous) paste-dispensing was down to 0,03mm with piezo-dispenser, and down to 0,0003mm (or 300 Nanometers!) with a new invented methode, I've developed around 2003 for a customer test, that wasn't implemented/developed into a real project.

So there is some more "room on the bottom" for optimizing FDM/FFF-printing, even with plastic materials -- but my intention is to combine different methodes into the fabbing process to get "smart" multimaterial parts


@o_lampe:

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o_lampe

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VDX
Now restarting again with my new company

Viel Glück damit, Victor!
...suchst du noch Mitarbeiter?

... möglich, im Projektantrag ist die Neuanstellung eines Technikers/Monteurs vorgesehen

Wir sind sowieso auf "Wachsen" ausgerichtet - wird aber noch etwas dauern ...

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

I am using my dual x prototype printer for a year now and i love it. Dual materials give you a flexibility in designing parts that is phenomenal. While dual x is a bit mor complicated than simple dual nozzle, the speed advantage and ease of use, once calibrated, is great. The clone capability is also nothing to snear at.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

My stance to begin with was that multiple nozzles are not needed, they get in the way and multicolour printing is a bit of a gimmick for the most part. Sure, you can make some cool looking two tone parts but there is not much you can visualise with two colours. To have any use, it has to have a good repertoire of colours. If you really needed it, you could probably print the parts separately and glue them together or paint them. SLS wins out with some pretty impressive inkjet full colour printing on ceramics.

The same can be said of removable support.. proper part design can eliminate overhangs, or at least takeaway the harshness of its effects on print quality. But, what about the practical applications? If you want any form of fluidity in your design you often have to break these rules.
If you are prototyping parts, you need them to be able to emulate the shapes produced by other technologies such as injection moulding, and this is where PVA support material comes into its own. It also means you can start printing pieces at an angle, similar to SLA printers to really take advantage of the high resolution of your Z layers.

This is only skimming the surface. I've seen some great and highly functional/practical designs use multiple materials. FDM still ticks many boxes that other tech can't making it suitable for everyday usage like functionality, reasonable size, no lasers, no chemicals and you can break into the hobby for a damn sight less cash.

I think FDM is a dead end. It will remain popular with hobbyists because it is relatively easy to DIY, but it is too slow for mass market or low production industrial use. I think SLA will replace FDM for hobbyists because it's faster printing, easier to build, and they will tolerate the clean up after printing. Ultimately, one or two colors or one color and support material has limited use in real life. You really need full color and variable material properties (such as flexibility) throughout the print. The STL file will be replaced by files of voxels with properties assigned to each one and the print head will deliver.

Don't ask me how- if I knew that I'd be doing it.

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

FDM has a place, but isn't going to take the place of proper manufacturing. Its a very simple means to prototyping for fit and function, and making the 1-off item. Beyond that, the dual nozzle with support material does mean you can design anything without considering how it will print using support to fill in the "air gap", but dual color isn't really necessary. If you where after color objects, I think you'd be looking more at the sand-cast process rather than the FDM world.

Surely the easiest way to get full colour fdm is to colour the filament with an ink jet head as you deposit it. This might necessitate developing a filament which will absorb the ink and binds it, perhaps thermally, but this has to be easier than mixing hotends (which don't really mix the filament) or multiple nozzles.

I could get behind the idea of two x carriages one with support one with filament which can have varying z offsets without knocking the print off the build plate.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

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DjDemonD

I could get behind the idea of two x carriages one with support one with filament which can have varying z offsets without knocking the print off the build plate.

Using two different types of material is way more interesting than just a seperate support material.
I have printed combinations of hard and elastic materials to create inbuild dampers, joints, springs, handgrips, bushing mounts, motor munts etc. . Another greate use is to print iglidur, or any other low friction material, right into hard plastic components so you have inbuild bushings.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

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Srek
Using two different types of material is way more interesting than just a seperate support material.

Absolutely. Interesting observation recently - if you print ABS inside a PETG exterior the PETG keeps the ABS warm enough to eliminate warping.

That is indeed interesting. I tried something similar already and printed parts that had an ABS infill, but transparent TPU perimeters. Tough elastic outside with a hard and strong inside. The TPU alone is to soft for many uses, but in combination the two are pretty cool.
I wrote about it her [b.bonkers.de]
Also it looks cool to see the infill throu the transparent perimeters

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Nice idea. I like that, having 2 materials that way. Especially if the outer one is transparent. I have some neon yellow TPU that will look great over a bit of black nGen.
Now I have another reason to install my Chimera set. I need to find an extra 2 days per week I think. Oh bother!

As to making smaller filaments and nozzles to lower weight, I think it is more logical to remove most of the weight by using a Remote Direct Drive (RDD). That will reduce the weight dramatically as you remove the stepper from the moving parts. In our case, the extruder part is only 27 grams.

I do think that multiple filaments are the way to go. Have you seen what Deckingman is doing with his Diamond head? Very clever. Predictive colour changing, no change tower needed.

For me the ideal print head would be a 5 way color mixing head and an extra nozzle for a completely different material, for instance support. Or coating, like with the TPU/ABS combination.
Flip flopping in height so the 2 nozzles will not interfere with each other. Hmm, I better start on the design for the 6 filament extruder.

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Lykle
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Co-creator of the Zesty Nimble, worlds lightest Direct Drive extruder.
[zesty.tech]

Check this out: [www.prusaprinters.org]

Video: [www.youtube.com]

laser can be installed as an attachment to closer to any extruder...
so do get 3D printer and laser cutter combo unit for that!)

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We change the world by bringing affordable and open - source technologies
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I have been digging into this a little bit more and have started to do some design work on ways to use multiple filaments.

There are a couple of things that I have defined for myself as conditional decisions, probably the best way to describe them.

I do not want a system with 2 nozzles set at the same height, bound to cause trouble for me.
I looked at making a mixing nozzle so I could feed two filaments at the same time, but getting proper mixing is very hard to do.
Full colour would be awesome, but I am just not good enough for that yet.

For me there are 2 main ways to handle dual filaments.
A single nozzle with alternating feeds, like the Prometheus system. I want it small, compact and easy to install and use.
Advantages: Easy to install, calibrate and use. Height adjustments not needed, Can be very light.
Disadvantages. Need to retract one filament a lot before inserting the next. Only able to print roughly similar materials. No mixing possible. Need a purge column.

A flip flop system with 2 nozzles seesawing to keep the non active nozzle from scraping.
Advantages. Quick to switch, can print widely diverse materials. Works flawlessly with only 1 filament inserted. Possible ooze stop.
Disadvantages. Complex to design and build. Heavy (still) Usually a tall assembly. Needs a servo, so special control.

For now I will stick with testing out the single nozzle idea and the flipflop mechanism.

Some years back I started to design a printer for printing multiple materials, the main idea of which was to have an all moving X Y stage with an array of printing heads which could be moved into or out of the printing position, all non-printing ones being raised to stop from scraping. I made several in-the-plastic attempts at the multiple printing head mechanism and uncountable CAD renditions before I decided that sloth was the better part of industry (I couldn't be bovvered) View below of the CAD rendering of what got closest.



The XY frame works splendidly and now serves as a light milling machine for PCBs, Vacuum hold-down plates etc.. (seen working in [www.youtube.com] ) Any future attempt to try for a multi material will almost certainly use the multiple heads as used by Srek.

Mike

The only thing dead are peoples technical ability’s and there imagination to design and build a 3d printer/system that is better than the last one,,,
unfortunately people are morons !! –we live in age where our technology is advance but the people are as stupid as ever,,,

There are still to many people still clinging to old world point of views or are just plain closed minded and arrogant- (aka.. educated idiots)-
I find it best just to keep to myself and design /print / test ----- throw in bin and repeat,,,,,,

And your right 3d printing is in the B&W T.V Stage –


-=Mindless=-

No, people are not morons or stupid, they just are subject to the environment that feeds their imagination and that environment is marked by an almost total loss of debate and massive polarization: It is not possible to see further by standing on the shoulders of giants if you can't even acknowledge that they have shoulders. The loss of debate has been almost entirely caused by the internet: If somebody starts out with a slight belief that something is true then a quick scan of the internet will bring them so much positive reinforcement that no other idea can be believed. Technology itself as well as technical abilities are largely dying in the West but seems to be alive and thriving in the East - so don't worry, what goes around comes around.

Old world points of view are not necessarily wrong but both older and newer ideas should be probed to find their weakness and strengths - after all, if my generation had decided that many-billion-year-old-fasioned sex was too old fashioned and that we were happier with Rock, weed and LSD then there would be many fewer members on this forum.

Keep designing/printing/testing and let us know about the failures as well as the successes and we may get RepRap community build 3D printer into the colour era.

Mike

My feelings on independent X are mixed. Being able to print multiple copies of a part in one cycle is an massive advantage, but taking advantage of that feature requires identical hotends on both carriages.

I find that being able to use different nozzle diameters to speed up a print is perhaps even more compelling than printing multiple copies of a part.

I'd also need to really think about how independent X interacts with bed leveling, especially on large printers.

time will tell.
I think the current designs use up way to much space and reduce build volume, and create issues that cause machines to need to slow down, mass, power, ect.

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691175002
My feelings on independent X are mixed. Being able to print multiple copies of a part in one cycle is an massive advantage, but taking advantage of that feature requires identical hotends on both carriages.

I find that being able to use different nozzle diameters to speed up a print is perhaps even more compelling than printing multiple copies of a part.

I'd also need to really think about how independent X interacts with bed leveling, especially on large printers.

I solved this for my DuoCube by using a quick release print head change system that allows me to switch the complete Extruder with hotend in seconds.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]