What makes a good 3d printer

Talk about anything.
Post Reply
outsider
Posts: 49
Joined: Tue Mar 12, 2013 2:08 pm

What makes a good 3d printer

Post by outsider » Thu Jan 15, 2015 3:01 am

I've been wondering this question for a while now.
And after seeing the Make magazine 2014 printer review I have more questions then answers. (I'm a mechanical engineer and it bothers me that I haven't found a clear answer to this question anywhere yet)
http://www.makershed.com/products/make- ... -volume-42

I know there are hundreds more 3d printers out there that didn't get reviewed by Make magazine, but just looking at the ones that got reviewed, it seems like only a hand full ranked highly in most/all categories.
Some of the other printers scored high in some test and low in others, while other printers had just the opposite kind of results.

The electronics in the majority of the printers is the same arduino based boards, so that's not likely a contributor in the print quality.
So it all boils down to the mechanical structure of the printer.
What is important in the design of a great 3d printer? Rigidity of the frame? Minimal slop in x, y and z axis?

Is producing a 3d printer that performs exceptionally across the board still a black art?
adrian.
My Blog

ggeezer
Posts: 12
Joined: Thu Sep 12, 2013 2:19 am

Re: What makes a good 3d printer

Post by ggeezer » Sun Jan 25, 2015 12:05 am

What makes a good printer is good engineering and construction. You can go only so cheap before print quality suffers.
As an engineer, I design and manufacture laboratory automation machines and end use a lot of printed ABS and nylon parts. I have used Stratasys Dimension machines, Makerbots and my personal Afinia (re-branded UP) model 480 which is two years old and has been printing reliably every work-day. All do a good job (if you understand their limitations and design parts accordingly) but for the money, the Afinia is a very good choice for quality prints, particularly if you use Afinia premium filament. This machine has some drawbacks but all in all, for ease of operation, works reliably with good precision. People complain about the small work enevelope but my experience tells me that you cannot print a part in ABS or nylon that has a footprint of more than 4 inches in any direction without having unacceptable warping problems.
I'm sure that there are other good machines but it is a crap shoot deciding what to buy. Stratasys, Makerbot and Afinia are backed up by strong companies located in the USA that offer good service and support.
What most of the low-cost machines suffer from is lack of rigidity. If you accelerate, decelerate or change direction rapidly, particularly with tall prints, any flex in the mechanism, due to inertia induced forces, will result in overshoot and poor prints.

outsider
Posts: 49
Joined: Tue Mar 12, 2013 2:08 pm

Re: What makes a good 3d printer

Post by outsider » Wed Jan 28, 2015 6:07 pm

Am I correct to assume that any 3d printer will produce decent prints if the print speeds are slow enough?

The mark of a more sturdy frame pays off in ability to increase the print speeds (accelerations and travel speeds) and not have a frame that wobbles as the machine is printing.
I guess the smaller the mass that needs to be accelerated the better the print quality (generally speaking).
adrian.
My Blog

pleppik
Posts: 336
Joined: Sun Dec 11, 2011 2:14 pm

Re: What makes a good 3d printer

Post by pleppik » Fri Jan 30, 2015 2:30 am

outsider wrote:Am I correct to assume that any 3d printer will produce decent prints if the print speeds are slow enough?
Not necessarily so. There's a lot that can go wrong thermally and mechanically that printing slower won't fix. For example, if the hot end is designed wrong the filament can soften or melt too early in the hot end and clog. Or if there's too much play in the mechanical components, the head won't be positioned precisely enough for good print quality.

Just to give one example, for a while Makerbot was using plastic support arms for the build plate in its printers. These would soften and flex a bit as the printer heated up, causing all kinds of print quality problems (it doesn't take much when your layer height is a fraction of a millimeter).

chang
Posts: 45
Joined: Thu Aug 14, 2014 3:13 am

Re: What makes a good 3d printer

Post by chang » Fri Jan 30, 2015 3:35 pm

ggeezer wrote:People complain about the small work enevelope but my experience tells me that you cannot print a part in ABS or nylon that has a footprint of more than 4 inches in any direction without having unacceptable warping problems.
geezer, this is a good point.

oklok
Posts: 8
Joined: Fri Jul 11, 2014 11:57 am

Re: What makes a good 3d printer

Post by oklok » Fri Mar 06, 2015 4:00 am

What makes a good 3d printer

Depends of what u want, but for most I think this qualify:

1. Easy to print with, we want to print not fix the machine
2. Capable to print fast with good quality
3. Can handle different filament supplier
4. Easy maintenance, yes aftert printing many hours it need to be maintenanced, but pls, make it easy for us
5. Stable, will print like a horse withoug giving lots of bugs

I think these are the most important, then of course I can add this list up to 100 of point...but then we would not have a good pritner but the best 3d printer O=)
http://www.3dfilamenta.com - Market space for 3D Printing; Sell and Buy!

roller
Posts: 1622
Joined: Sat Oct 06, 2012 9:09 pm
Location: Brisbane, Australia

Re: What makes a good 3d printer

Post by roller » Sat Mar 07, 2015 7:44 am

I have designed, built and modded a lot of 3D printers for students, clients and myself. There are five main ingredients to a good printer that are universal:

1. Limited play. Rigidity is key as well as eliminating backlash. If the precision of the printer is poor, your print quality will be poor.
2. A great extruder design. You really want your extruder to run cool, have a good feed path with little tendancy to hysteresis nor excessive tightness to induce jams. Teeth should be deep enough so as not to fill with filament dust and have good strong bite on any filament.
3. Good software. Software needs to be smart, have good algorithms to reduce blemishes and be tightly tuned to the printer capabilities. Ideally you also want enough control to deal with different filaments.
4. Reliability. It needs to not rattle apart or be prone to going out of alignment over time.

The primary weakness in the Up is in no2. The design is decent but not great. The linear guides and sufficently thick metal construciton deal with 1. The software has access to great algorithms for removable support which is a printing panacea. And the up has a fairly proven design to meet 4 with the except of the weaknesses in the extruder design.

roller
Posts: 1622
Joined: Sat Oct 06, 2012 9:09 pm
Location: Brisbane, Australia

Re: What makes a good 3d printer

Post by roller » Thu Mar 19, 2015 11:53 am

chang wrote:
ggeezer wrote:People complain about the small work enevelope but my experience tells me that you cannot print a part in ABS or nylon that has a footprint of more than 4 inches in any direction without having unacceptable warping problems.
geezer, this is a good point.
I print 190x190mm in ABS often and any warping is unacceptable ... warping is a problem which has solutions.

Post Reply