Advice sought re: 3D printer purchase

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ajoeiam

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Greetings

Looking at getting myself one of these gizmos.

One problem is that this is a Linux house - - - - haven't run M$ stuff in years!

Second I was thinking of trying to get something a bit bigger than the 250 x 250 x 200 envelope.
Seems that the bigger models get really expensive in freight.

Hoping you guys have some ideas.
(Maybe better to start with a smaller model?, way to get in Canuckistan w/o breaking the bank!!! (Important!!!!!!!!) - - - anything else)

Anyone roll their own?

TIA
 

lohring

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I've had a Prusa Mk 3 (now Mk3S) for years. I built it from a kit and upgraded it as the upgrades came out. It's been mostly trouble free. I believe the kit build helps in dealing with the various problems that any new user will have. Prusa's firmware is in hex so should be machine independent. Their slicer, that I highly recommend, will run on a Chrome Book. "Luckily Google now offers a containerized Linux on modern Chromebooks out of the box and PrusaSlicer runs in the virtualized Linux environment nicely. " The printer firmware can be installed with the slicer. Prusa has been very helpful. If you ask in their forum, you should get advice.

Lohring Miller
 

ddmckee54

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My printers are both in the 200x200x200mm range and I've printed some pretty big crap. You can get a decent printer in that size for a couple of hundred Canuckistani pesos.

What do you want to print that's bigger than 200x200x200mm? Just remember that the bigger the print, the longer it'll take to print. I've found that the number of layers has more of an effect on print time than the area of the layer.

Also think about the fact that prints fail - a lot. Let's say you have a part that will print in 44 hours on your big printer, but you can split that part into four 11 hour prints on a smaller printer. An 11 hour print that fails when it's 90% complete is a lot less heartbreaking than a 44 hour print failing at 90% complete. (Also scraps less filament.)

Don
 

swood1

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Lookup artillery X1. Has a good size working envelope.

Steve
 

AndrewW

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Like Lohring, I have a Prusa MK3S. A well made machine which produces really good prints. As Lohring suggests - seek advice on the Prusa forum regarding Linux compatibility.
Good luck!
 

Bazzer

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I have used and recommended to others the Dremel/Flashpoint Dreamer printers, whilst a little smaller than some printers they are totally enclosed and UL and CE rated and have Bosch engineering behind the Dremel version. These printers work great straight out of the box, no fiddling, they print a wide range of PLA and flexible materials.

Software wise I use Simplify3D, this will run on Linux, I find this software gives a good degree of control over the printer, for example the minimum layer height in the Dremel specifications is 0.1mm, I often print out detail areas at 0.05mm layer height and then switch within the same part to 0.25 or 0.3 in areas of less detail.

Attached are a few samples of parts that I have made on the Dremel 3D20, the yellow parts are patterns to produce the moulds shown and the composite fuselage from that. I have successfully printed fuel tanks, including the caps and soft bungs.

The picture of the model flying is from the mould and patterns shown, the model also has upswept 3D printed wing tips.

All done on second hand £200 ($300) dollar printers.

I mostly use Protopasta filaments.

B.
 

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ajoeiam

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Very interesting - - - - - so the suggestion is to keep with a smaller unit and then join pieces to form bigger projects if necessary.

Have any of you printed in a 'urethane'?
Suggestions for a url - - - - looking for a chart re: material xxx is better at this yyyy kind of thing?

Hopefully not too many questions!
 

Bazzer

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I have printed with flexible PU (shore hardness 95), that is what the bung in the fuel tank was done with, feeding the flexible PU is a challenge as it buckles between the feed mechanism and the nozzle, but I have managed to get quite a few PU components out.

My favourite material is the HT carbon fibre filled PLA from Protopasta.

You can see where I used it as an exhaust strap on this OS60 test stand. Has not melted yet.

What ever printer you get it will never be big enough for the biggest job, it was mentioned that loosing a big print after say 40 hours will be disappointing, that is another reason to break the job down to manageable sizes.

I don't specifically know of a resource that tells the info that you ask about materials, sorry.

B.
 

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CraigLD

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Lookup artillery X1. Has a good size working envelope.
I've had an X1 for not quite two years, bought it on Amazon for a bit under $500. In general my wife and I are pleased with it, but have had to rebuild the extruder more times than I like to think of. My wife has printed items that took the entire 300 x 300 x 400 mm footprint, but I have mainly printed smaller items such as containers for holding small parts.
 

stanstocker

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Morning Folks!

Cura works fine on linux here. Only thing is that it seems much happier, or even workable, if you save the generated G code to a card and use that in the printer rather than drip feeding the printer from the computer.

What isn't so fine is the CAD side, although quite a few folks do the more free form organic sort of stuff in Blender which is naturally just lovely on linux.

So... You can remain in a pure linux based environment using open source tools for 3D printing, provided you are comfortable with FreeCad or Blender to create 3D models, or are only interested slicing existing models rather than creating new ones. No doubt there are other options, seems over the years I've tried quite a few design programs on linux with varying results. I'm not a good Blender driver, but if what it's good at was what I wanted to do I'd sure learn to use it well.

We've banged around FreeCad on another thread, although a linux bigot I must admit to using Alibre Atom these days, although not enough to claim any sort of mastery. Sadly for much of the CAD/CAM side of the world I've had to allow the applications to dictate the OS in use. I guess that actually make sense as you do spend more time in applications than dinking with the OS.

Cheers,
Stan
 

awake

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ajoeiam, in my experience, Linux is very well supported for 3d printing ... in fact, I suspect a lot of the development of the home/hobby 3d printers was done in various Linux environments.

There are three stages to the process: 1) Create or acquire a 3d model; 2) "Slice" it (generate g-code that will print out the model); 3) Send it to the printer and print. To keep these posts from being too long, I will break these 3 stages up into 3 posts.

For #1, the easiest (but often not the best) approach is simply to download a model from any number of sites such as Thingiverse. But typically even if I get ideas from an on-line model, it is never exactly what I need, and I wind up creating it. And of course, most of the time I am creating something "from scratch" based on something I need, without ever looking at what others may have done.

To create a 3d model, there are several LInux-friendly options; the two I use most are FreeCAD and OpenSCAD. These represent very different approaches, and how to use them probably needs to be a separate discussion. Note, however, that in addition to simply designing a 3d model, you need to learn how to think in terms of what a 3d printer can and cannot do - particularly with regard to clearance and overhangs.

Take a simple bearing pocket in the bottom of a part - let's say the bearing is 32mm in diameter, 10mm thick, and there should be a 26mm clearance hole after the bearing. Easy, peasy, right? Just put a 26mm hole through the part, and a 32m pocket 10mm deep on the bottom. And ... it will not be pretty.

Problem # 1 is that the process of filament printing requires a certain amount of "squish" (highly scientific term) of the molten plastic against the previous layer. This "squish" means that an interior hole that you specify as 32mm may actually come out as 31.8mm - you have to build in some clearance, and that generally requires some trial and error, not just of the printer, but of the type of filament AND the layer height you are using to slice it.

Problem # 2 is the overhang - at the point that the pocket narrows from 32mm to 26mm, you are attempting to print "horizontally," and it is going to droop and be an ugly mess UNLESS you enable supports - pillars of plastic that are printed alongside the "real" print - but supports can be a pain to remove. However, if instead of a 90° transition, you transition from 32mm to 26mm using 45° or even 60°, it will print just fine WITHOUT supports.

This is just a rough and incomplete overview, and at first it seemed a bit overwhelming to me, but it didn't take long to work my way up the learning curve - of course, still learning!
 

ddmckee54

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I agree with Stan regarding using an SD card for printing vs. printing direct from the PC. The only time I've ever hooked a PC up to my printers is when I wanted to suck some parameters out of the printer. I always print from an SD card. That frees up your computer so you can use it for something else while your printer is humming along.

Don
 

Scott_M

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awake

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#2, slicing:

The 3d software mentioned in #1 above will generate a 3d model, most typically in .stl format. A bit of a side comment - there can be .stl models that are not well formed; the model needs to be a complete "watertight" surface, but some on-line models will have holes, inverted features, etc. Some slicer software and some 3d software (such as FreeCAD) can attempt to "repair" a faulty .stl file.

The .stl or other model has to be analyzed so that it can be processed in the way the printer will print it - in a series of layers. The software to do this is called a "slicer." Fortunately, all of the major / common slicers are available on Linux: Cura, Slic3r / PrusaSlicer, and even the commercial Simplify3d. The only problem would be if you buy a printer that requires the use of a proprietary slicer that only runs on Windows.

There is some jargon to learn with slicers - again, a bit overwhelming at first, but turns out not to be a difficult learning curve. You can reduce it to just a few basic parameters: 1) Layer height (how thick each layer of plastic is; as two examples out of many, .25mm give relatively coarse results, but is faster; .1mm gives very fine results, but takes longer). 2) Fill density - normally models are printed semi-hollow, with solid perimeters and a honeycomb or grid or other pattern of in-fill. Denser takes longer, and adds a bit of strength, but rarely do I go higher than 15-20%, and often I print at 10%. 3) Number of perimeters and top/bottom layers - as noted in the previous item, you generally will have several solid layers at the top and bottom, and several "rows" of continuous filament around the perimeters of each layer. A typical setting is 3 for top, bottom, and perimeters. More takes longer, but increasing these reportedly adds more strength than increasing fill density.

Those are the basic parameters ... but there are tons of additional settings that go into a successful print. Some slicers try very hard to hide the potential complexity in order to make it all as simple as possible (particularly true of a proprietary slicer included with a printer), but I highly recommend digging in to learn the underlying settings; this will give you much greater control over the results you get.
 

awake

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#3, sending to the printer:

The slicer generates g-code, which is simply a text file (though usually with a suffix such as .gc or .gcode or such) containing lines such as "G28" (perform a homing routine), "G0 X45 Y82.5 Z0.2 F3000" (move to coordinates 45,82.5,.2 at a speed of 3000 mm / min). You can examine this file and if necessary modify it manually, though that can get quite tricky quite quickly.

To actually perform the print, this text file has to be processed, line by line, by the printer. How the file gets to the printer will depend greatly on the particular printer. Most have a USB port, and can connect to a computer running software that sends the gcode out to the printer line-by-line, much like a computer would print something to a laser printer or dot-matrix printer (remember those??). To do this, you use a "sender" program such as Pronterface or Repetier (both free and open source, and available for all platforms including Linux).

The problem with this approach is that 3d printing is slow - a very small print might "only" take an hour, while a larger part - let's say 6" in diameter, 3" tall - could take a day or more. Print times will be greatly affected not only by the overall size, but also by the layer height, the number of top/bottom layers, the layer height, the number of perimeters, the layer height, the infill density, the layer height, the number of features, and the layer height. :)

Rather than tying up a computer sitting there just dribbling out the lines of gcode, most people prefer to have the code transferred to the printer in some fashion. Very common is to have an SD-card interface on the printer. Put the SD-card in your computer and copy the .gcode file to it; put the SD-card into the printer, pull up the list of files on a menu, and select print. The printer goes on its way for the next 1 - 100 hours while you do something else. Unless the power goes out, or the filament jams, or so on - you really should never leave a print completely unsupervised, though it is hard not to leave it when you have to sleep overnight!

Another popular option is to use a wifi interface to the printer. Some printers have this built in, but if not, you can buy an inexpensive Raspberry Pi and set it up with something called OctoPrint. This creates a web-based interface to your printer; from this you can directly manipulate the printer (move the head to a certain position, or turn on the heat bed, or so on - and you can also directly send gcode to the printer), or you can upload your .gcode file to OctoPrint and it will manage the printing process.

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In spite of three lengthy posts, I feel that I have only scratched the surface ... but the good news is, there are tons of forums, YouTube tutorials, and more. And you can get started with the basic settings and methods, and then get more sophisticated as you move up the learning curve.
 

Mike Henry

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PrusaSlicer apparently runs under Linux, per the download link here:


It's free, so why not try it out? It can be customized for other printer brands & models, I think but to my mind there's not much reason for anyone to look beyond Prusa for their 1st printer. Buy it as a kit to save a few bucks and learn a bit about how it works. The manual is available on-line and features continuously updated Q&A on build issues that others have encountered. The forum and Prusa Facebook groups can be a wealth of knowledge as well, though FB tends to be a bit of a wild west area.
 

Bazzer

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Price would be one reason to look at what is available, skeleton open structure would be another.

For sure they are good printers though.
 

awake

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On printer brands, I would agree that it is hard to go wrong with a Prusa. But it is also hard to go cheap ... yes, there is a relationship there between what you pay and what you get, but if budget is a factor, there seem to be a lot of mostly-positive reviews of many of the Creality and similar brands, and I believe some of those are available in a 300mm / 12" size rather than the more typical 200mm / 8". I have no personal experience with any of these brands, since my own 3d printer is my own home-brew design, so no affiliation at all - just what I have seen from YouTube channels such as Makers Muse and Thomas Sanladerer.
 

Stone

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My first few 3D printers were VERY frustrating experiences. It took me days or weeks to solve the many issues that affect print quality. Reprinting with the same settings / method was also not consistent.

I have had 2 or 3 printers, including a very expensive $2000 model which had a 400mm x 400m x 400m build capacity. All of them gave problems, the most frequent been, getting the print to stay stuck to the deck. This is a universal 3D print problem. People overlay their build decks with glue, blue tap, slurries, etc to try improving the stick. If these methods do manage to hold the job on the build plate, it makes it a pain to have to reset between each print because you must clean of the “additives” and reapply.

Then I bought a Creality CR-10 for my teenage nephew because I wanted to encourage him to learn CAD and CAM. In a day he was up and printing! The much cheaper Creality CR-10 totally blew away my $2000 specialized printers.

Within a month I bought my self the Creality CR-10S pro. What a relief! What a pleasure! It has an impressive 300x300x400mm build volume. But that is not what makes it nice. It is nice because it is easy to setup, easy to maintain, printers are fantastic. It just works. I gave away all the other printers.

It automatically levels before each print and then away it goes. Best of all the job sticks, I mean really sticks. Initially this was a problem because it was very hard to get the job off the build deck it. However, with the on vent of a flexible build plate that magnetises onto the printer, printing and removing is a 30 second breeze. Once the job is finished you take the build plate off the magnetic under surface in a second, give it a bend and job pops straight off with ease. Now I can quickly set up with auto levelling, print without worrying about lifting, and pop it of afterwards. Printing has become a pleasure. I found it impossible to get the job to stick to the flexible PEX build surface, but the flexible Polycarbonate (or PC) sticks perfectly, just like to PC that comes standard on the Creality CR-10S pro.

Creality CR-10S pro also has a geared feed which many printers do not have.

I do my design in a CAD software (Fusion 360, Solidworks, etc), save as STL. Then drag and drop the STL into Simply3D which generates the Gcode and saves it to a microSD. Put the SD card in the Creality and print. No messing about with all sorts of frustrating setups and tapes and what not.

Simply3D is a pleasure to use (PC and Linux versions available), and with a bit of google power you can find the pre-configured settings (small FFF file I can send you) for Simply3D that matches a Creality CR-10S pro that produces amazing prints straight off the bat. The combination of Simply3D ($149) and a Creality CR-10S pro ($539) makes getting the print done painless.

You can buy a cheaper machine, and then try adding the auto levelling, geared feeds, and many other tweaks, you soon discover are needed to try get consistent prints, or just buy the Creality and enjoy a machine that just works first time.

As for the size, bigger prints take longer, but when you need it, you need it! It is not always possible to print smaller parts and assemble. On the rear occasion I need make a big print, I setup in the morning. Start the print and let it run for the day or so with confidence it will not shrink and lift off the corner after printer for hours or a day (this very frequently occurred on other machines) forcing a reattempt from scratch.
 

Stone

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Just reading my post above, sounds like I own shares in Creality…LOL.
I do not, I just love things that been thought out and designed to work properly first time.
 
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