tool head impact on print quality  

Re: tool head impact on print quality

Smaller nozzle and higher resolution (more precise) extrusion. Maybe other things as well.

Peter

Re: tool head impact on print quality

aslo, the e3d titan aero has ageared extruder drive so probably more steps per millimetre (about 160% of bondtech steps/mm) to provide better control of extrusion at slow speeds with small nozzles and low layer height

regards Joan

Re: tool head impact on print quality

If you want to see really, really small prints made using nozzles smaller than 0.25mm, take a look at this thread in Printrbottalk.com: http://www.printrbottalk.com/forum/viewtopic.php?f=28&t=2755&p=18304 . The Printrbots used in these prints had geared extruders (and they were using 0.3mm filament going in).
Of course, in X, Y, and Z there's no difference between the available resolution on the Printrbots and on the Prusa's - except that the Prusas are better due to having a more rigid frame. The geared extruder steps per mm using 3mm filament on the Printrbot was in the ballpark of 500 - 600 steps / mm

Re: tool head impact on print quality

Lulzbot doesn't seem to really want you to replace nozzles from what I read while researching my second printer. They seemed to prefer you buy a brand new $300-$700 print head instead of replacing worn out or just to go to a different sized nozzle. There are instructions on how to replace the nozzle by the community, but I never saw any document from them even mentioning nozzle replacement. Being an open printer like Prusa, I found that very strange.

Re: tool head impact on print quality

I didn't think of the extruder control... 🙂

Thanks for the answers (I don't know how to choose a best answer now.. :))

I it puzzled me, but now I get it.
(I'm not considering a Lulzbot at the moment, but thanks for the comments!)

Re: tool head impact on print quality

The geared extruder steps per mm using 3mm filament on the Printrbot was in the ballpark of 500 - 600 steps / mm

Wow. That makes me wonder if there isn't SOME point at which it won't matter (much) anymore. Sort of like 4K vs. HD--the human eye can't see that kind of resolution at normal viewing distances on less than wall-sized screens.

With 3D parts, it may come down to tolerances and fitting things together, but unless we're talking rocket science (i.e. NASA), there are still industrial tolerances beyond which it's not worth the expense/trouble.

...not to mention the time it'd take to print something that detailed... :geek:

Re: tool head impact on print quality

RetireeJay wrote:
The geared extruder steps per mm using 3mm filament on the Printrbot was in the ballpark of 500 - 600 steps / mm

Wow. That makes me wonder if there isn't SOME point at which it won't matter (much) anymore. Sort of like 4K vs. HD--the human eye can't see that kind of resolution at normal viewing distances on less than wall-sized screens.

With 3D parts, it may come down to tolerances and fitting things together, but unless we're talking rocket science (i.e. NASA), there are still industrial tolerances beyond which it's not worth the expense/trouble.

...not to mention the time it'd take to print something that detailed... :geek:

That's only the Extruder steps. The Printrbot uses the normal belts with 80 steps/mm in X and Y. So you just send a lot of steps to the Extruder, but all those steps don't really affect print quality. The geared extruder was used to generate enough torque to push 3mm filament through the hot end. The little tiny prints in the linked forum thread only took seconds or minutes to print, they used so little plastic.

Re: tool head impact on print quality

So you just send a lot of steps to the Extruder, but all those steps don't really affect print quality.

Isn't that what I said? 🙂 (sorta?)

I'm sorry, I should have been clearer. I was opining in more general terms.

Back to the extruder, are you saying that more steps = more torque?

Re: tool head impact on print quality

Back to the extruder, are you saying that more steps = more torque?
Well yes, but only because of the geared connection between the motor and the hobbed bolt. You can see a picture of the geared extruder, also called a Wade's Extruder here. http://www.printrbottalk.com/forum/viewtopic.php?f=16&t=3484
If you bought a motor with more steps per revolution and used it in place of the one Prusa supplied, you wouldn't get more torque because of the extra steps.

Re: tool head impact on print quality

Jörg, just out of curiosity, what are your decision criteria for chosing a printer?

Re: tool head impact on print quality

Jörg, just out of curiosity, what are your decision criteria for chosing a printer?

I'm more or less decided on the Prusa mk3, but as I am currently abroad I have to wait till January to buy anything like this (or I'd have to ship it). So the more or less solely depends on "sudden super things that come out in the next couple of months and become rapidly available"... 🙂

My main criteria is (as it is my first 3D printer) that it should just print. This sounds stupid, but I've read many things about cheaper kits that may be very capable but require a lot of tweaking to get the output correct. This tweaking can be fun, but my main purpose is to print objects, not to tweak (I would think that to be something for a second printer or so, when you already have some experience with how settings affect prints). I know that any 3D printer requires tweaking and work to get a good output, but I would like to start with a good platform as to minimize frustration. I also would like it to be safe, and am weary of devices that have safeguards disabled or use low quality components.
Initially I looked at cheaper printers (you know the initial find "wow, you can have a 3d printer for xxx euro! 😯 "), but after reading various reviews it seems the Prusa seems to come out very well out of all of them (the realization: "hmm, it costs more than xxx euro but does seem better 🙄 "). This automatically led me to the Prusa forum and the wealth of advice you can get here is another argument for the printer (people have similar platforms, so advices are more targeted and less generic).
For my purpose, an SLA/DLP printer may be better suited (not sure), but I don't want to venture in that chemical mess; besides I also see some possibilities with a FDM printer that the SLA/DLP do not have. So I'm willing to sacrifice some detail for that.

My purpose is not professional, and completely private. So it is a bit of an expensive "toy", but something I think I will have fun with. 😀

My question on the toolhead was not really to have a deciding argument, but rather to educate myself more on the 3D printers. 🙂

Re: tool head impact on print quality

Some advice after i sometimes pulled my hair even with this excellent printer:

1. Be absolutely sure the pinda-probe is down far enough, it will save you scratches and calibration errors
2. Replace the y-pully shaft with a smooth one at least i had terrible squeaking and abrasion with the default screw
3. center the Extruder-pully shaft in the printed part and secure it with hotglue on both sides, mine came loose somehow and printing was almost
impossible and of abysmal quality until someone pointed me in the right direction

These are of course only my fixes which others might find questionable but after applying them i have a printer that just works
Sorry i'm quite offtopic now too just found it worth sharing 🙄

Re: tool head impact on print quality

Jörg, it sounds like you got a good understanding of the topic and if you are looking for a reasonably priced reliable gem workhorse the MK3 is hard to beat IMHO.

The flex plate alone is a great feature. I had the MK2 for only 2 weeks before selling it for the newly announced MK3 and getting prints off the print bed was not easy at all!

Print quality on the MK2 was actually better compared to 2017 MK3, but with the new firmware and profiles it has been a very reliable machine for me!

Contrary to others I have had no mechanical issues, I built it carefully and it has been working without issues. I did install better rods and bearings, but not really necessary.

I asked because I think the MK3 sits in a sweet spot, but with limitations in terms of print size (not the best for tiny and not possible to print huge) and materials (super exotics).

I also watched a friend struggle with cheaper printers and was very happy to have spent more. I prefer using my time to design and print stuff than to rebuild and tune my printer...

The MMU is also an interesting option, I am just not sure how it would work with materials that need different temperatures.

Anyway, as said you seem to know what is important to you and I can only say I am very happy with the Prusa MK3

Cheers! George

Re: tool head impact on print quality

Jörg, it sounds like you got a good understanding of the topic and if you are looking for a reasonably priced reliable gem workhorse the MK3 is hard to beat IMHO.

Well, I have considered 3D printers in the past, but never made the jump. Now I decided to do it, so I started educating myself on the topic. 🙂

I asked because I think the MK3 sits in a sweet spot, but with limitations in terms of print size (not the best for tiny and not possible to print huge) and materials (super exotics).

At the moment, I'm not too bothered with maximum print size, so that does not limit me. Detail is more important to me, but apart from going sla (which I don't want to due to the chemicals), there may not be many better options at a reasonable price point and without too much hassle. 🙂
Although upgrading is a possible with most open source printers, I like the fact that prusa provides upgrade paths with their hardware and support. So that is also interesting, basically contribution to my feeling that it is a good platform to start with.
Thanks for the comments!