Extruder decision advice for library - FlexiDually, Dual Extruder

I am looking for advice. I am trying to make a good decision for my patrons. 3D printing at my library is new. I did my best to read as many post related to my questions as possible. Here is where I am at. I am purchasing accessories for a public library users, so there will be a range of printing needs. We have a Taz 6 and a Printrbot Play. We have the grant money now and won’t really have it for sure in subsequent years. Basically our budget on going will be for basic maintenance and filament (which depends on use).

I am looking to definitely provide Dual Extrusion and also Flexy filament options. I had been prepared to fork up the money out of Grant money to buy the Dual extruder, FlexyDually, and Flexy - about $1,300. However, after reading some posts here I see that there are people that are printing their own extruder heads or attaching a single Extruder to the FlexyDually (swapping out the Flexy Extruder) I am unsure what is the best approach. Also, I believe I read that a best practice is - if you want to offer different types of filaments you may want to have a dedicated Extruder for each - not just a nozzle? We have only printed with PLA and nGen so far, I am not sure how ABS will print, we do not have an enclosure. So if printing parts with ABS is necessary that may matter.

So my question is should I –
A) Just buy all three - You’re over thinking it, this opportunity won’t happen again.
B) Buy just the Dual Extruder and Single Flexy (with the idea I can put the Flexy on the Dual for a Dual flex and non-flex extruder) - spend the rest on filament.
C) Buy just the FlexyDually and Single Flexy (with the idea I can put the single non-flex extruder on the FlexyDually to make a Dual non-flex extruder) - Aside: Can the Flexi Extruder from the FlexiDually become a single Flexy?
D) Find the money - Just buy all three and add another Single extruder for “exotic” or metal filaments.
E) If I were to buy just B or just C - would you buy a second single Extruder for “exotic” or metal filaments.

Other info:
Taz 6
.5 nozzle
I am planning on getting a set (maybe two) of http://www.matterhackers.com/store/printer-accessories/e3d-v6-extra-nozzle-fun-pack-3.00mm
Filaments looking at providing: PLA, MOLDLAY, T-GLASE, NGEN, HIGH TEMP PLA, NinjaFlex, SemiFlex WoodFill, SteelFill, possibly ABS, possible PVA, possible HIPS
We have no enclosure
I hope to participate in Enable the Future
Considering purchasing Simplify3D

Thanks for you collective wisdom and advice,


I’m no expert, in fact, I’ve really just started in the process of 3D printing a month back with a TAZ 6. But I have an engineering background, so it may be easier for me than others.

However, let me give you my take on things.

1st of all, the TAZ 6 supposedly can take 1.75mm filament (though not supported) and works well. I mention this as there are more choices in this size, and may be cheaper.

2nd, make sure you check Amazon prices, Newegg prices as well as Lulzbot and Matterhackers for filament and tool heads. Amazon prices vary often, so check often. The dual head is typically about 6% off at Amazon. Filament prices vary a lot (as well as quality) so check all these sites. If there is a Microcenter near you, they carry some of these things, and occasionally (read rarely) they have some of these things that they do carry on sale in store.

Dual Extruder and FleyDually. I have been experimenting with the start, start2, end and end2 gcode. The initialization files that come with Lulzbot edition of Cura for the Dual heads seem to be limited for types, e.g. PLA-PLA. In fact, finding that page that has some configuration files is difficult on the Lulzbot web pages. However, if set up correctly (and I don’t know if their Cura or the new version of Cura), you can use a either dual extrusion head as if it was a single head (so you can have both filaments loaded as choices). Simplify3D may well be worth it, and may be better at this as it comes. It is considered the best slicer, and I have yet to use it. But Simplify3D may also be cheaper for an Educational facility such as a Library. Same thing may also be for Solidworks or other paid CAD or support software.

So, in my opinion the single head that came with the TAZ 6, a Dual Extruder and a FlexyDually may be all you need for the greatest flexibility with the lowest cost. I would probably leave the Dual Extruder as the primary tool head though.

The tool head cable pins can be easily damaged if not inserted carefully when changing tool heads, so I recommend changing heads only when absolutely necessary, and limiting those that can. I changed the tool head screw that holds it on (an M3 x 10mm screw) to knurled knob screw, which allows me to change the head without a tool. I have a lot of spares of these, and if you wanted one, PM me, and I could mail it to you.

Usage by many people issues - I have found if you load the wrong firmware (which you should do when changing heads, particularly switching between dual and single) It will do bad things in the Homing process (noisy things like pressing the bed down near the Homing switch) which can’t be good. Wrong configuration files can mess up heads and the bed. Bad removal techniques will destroy your PEI bed. So what can you do? 1st of all create a checklist for changing heads so users can always follow the sequence. Teach users how to prepare the bed (e.g. tape, glue, etc) if needed, how to remove the objects from the bed, and how to insert and remove filaments from the tool head. Have people be careful of the tool head extruder heat (up to 300 degrees C) and the bed heat as well when turned up to high temperatures. You don’t want people to get burned! And tool usage and safety (e.g to remove objects) is paramount.

Learn and teach how to align the Z axis when it goes slightly off on one side or the other.

Consider using Octoprint (or octopi) to run the actual gcode, so that you don’t tie up a full computer while printing, plus you can stream video so patrons can watch their print remotely. You can use the Mattertouch product, but cost will be higher.

Don’t use ABS unless you really, really need to. The smell may be bad for a library environment unless you can enclose it and vent it out. Nylon may also require venting.

Use the least damaging filaments (non-specialty) in typical usage (nGen, PLA, XT, PETG) to preserve your tool heads. I believe the nozzle wear is the primary issue, and while can be changed, is not a particularly easy thing to do.

Stick to a minimum of colors, as they can be painted with various degrees of success depending on type. I would stick mostly to white or a light gray.

Let me just repeat, I am far from an expert at this point and others may be much more qualified to talk on the subject, but I think all my points above are correct, particularly for a shared environment.

Good Luck.

First of all, providing a 3D printer for general public use is a great idea and I hope it catches on. With that said, offering 3D printer to the general public sounds like a maintenance nightmare. :slight_smile: Its not a technology ready for general consumption…

To your choice of toolheads. The single head is easiest to maintain and a good start. Understanding that you probably only have one chance for funding. The Flexydually is probably the best choice for flexibility and diversity. This would give you a base for deriving other toolhead permutations. For instance, print a second regular Wade’s extruder body to replace the Flexy for dual color prints of harder filament types… print another single toolmount to build a Flexystruder. Keep in mind the dual extruder requires more maintenance, and adds another layer of complexity.

If you haven’t considered an enclosure (cabinet of some sort), I recommended setting aside money or allocating into your budget. It will help your prints overall… and maintenance of the printers.

As you offer the service, I would limit the filament types. Each requires tweaking for individual print environments. PETG for ease of printing, ABS for durability… limiting colors for possible bulk discounts. TPU probably wouldn’t be my first choice as an offering.

Hope that helps in your decision.

Most beginning 3d printer users would be more frustrated by a dual extruder setup than they would a single extruder setup. if you have patrons that would not be frustrated by a dual setup, go for it. Otherwise I would recommend avoiding them for now.

ABS filament smells a bit. For a library environment, unless the printer will have its own room with ventilation, I would consider not offering ABS initially. You may also want to initially avoid offering woodfil or steelfil or any of the material impregnated fillaments as they are very abrasive to the hotend nozzle and you may end up having to replace the nozzles, which will void the warranty.

You may want to also contact Lulzbot and see if a public library would qualify for their educational pricing program.

Running a dual extruder is at least 10x more complicated than a single extruder. I would run as fast as possible from the idea of offering it to the general public. Based on the current level of 3D printing software maturity (and hardware as well) I think that you will become extremely frustrated with dual extrusion and end up abandoning it. IMO dual extrusion is awesome for R&D engineer and tinkering types and that’s about it for now.

P.S. Simplify3D is not simple, it’s far more complicated than Cura. It is however more powerful especially if using a dual extruder. That said, some of the features on Simplify3D do not play nice together. That is if you enable the wrong collection of features you will get unexpected results. I’ve sent numerous messages to their technical support on things that don’t really work well and suggestions for improvements. Be prepared to spend a few weeks testing and playing with it to discover it’s little quirks and if you haven’t already done so, learn how to read gcode. Otherwise you will likely become very frustrated with Simplify3D and dual extrusion in general.

I don’t think it is that much harder from usage, although probably much harder from the CAD point of view. However, if the money is available, better to buy it now rather than not have the money should you want it.

Each tool, including Simplify3D, have their strengths and weaknesses. Better to have a variety of tools for learning purposes, allowing users to learn from all, not just one of them. After all, it is a Library (learning center). Since most of the other slicers are free, paying for 1 good, popular non-free slicer is not too bad.

I would add a Solidworks Pro, Sketchup Pro, and maybe Autodesk software if low priced educational ones can be utilized in the Library setting along with computers to use them on.