Prusa MINI: Smart and compact 3D printer • Hacker News Board

Re: Prusa MINI: Smart and compact 3D printer

#101

Post by [deleted] » Sun, Oct 13, 2019, 4:34 AM UTC

dfasdfasd wrote: post #77

jrockway wrote: post #58

Earlier quoted context omitted.

Yeah, I posted a few comments here without actually watching their marketing video, and didn't realize it had those two things. Upgrading to get those features seems like a good idea, to compete with the cheaper models. I don't think I would have engineered a new board and control stack just to get a web interface and a screen. Their last model (the i3 MK3S) has headers to accept a Pi Zero, and that seems like a good…

> I just want a USB serial port that accepts gcode. I have plenty of computers with much better screens (and SSL stacks) around for doing something more powerful ;) That's fair, but then you've added an extra processor which adds a lot of cost. I don't want to tie up a full computer and the associated space just to run my printer. Many people don't have a spare computer they can dedicate to printing either.

[deleted]

Re: Prusa MINI: Smart and compact 3D printer

#102

Post by jrockway » Sun, Oct 13, 2019, 4:34 AM UTC

dfasdfasd wrote: post #77

jrockway wrote: post #58

Earlier quoted context omitted.

Yeah, I posted a few comments here without actually watching their marketing video, and didn't realize it had those two things. Upgrading to get those features seems like a good idea, to compete with the cheaper models. I don't think I would have engineered a new board and control stack just to get a web interface and a screen. Their last model (the i3 MK3S) has headers to accept a Pi Zero, and that seems like a good…

> I just want a USB serial port that accepts gcode. I have plenty of computers with much better screens (and SSL stacks) around for doing something more powerful ;) That's fair, but then you've added an extra processor which adds a lot of cost. I don't want to tie up a full computer and the associated space just to run my printer. Many people don't have a spare computer they can dedicate to printing either.

I just use a Raspberry Pi in a case that mounts to my i3, but I do realize that $35 is an order of magnitude more expensive than even an ultra luxury ARM microcontroller. I also realize that the Micro SD storage system that the Pi uses would never work in a consumer electronics product. (This is why the compute module has eMMC.)

Re: Prusa MINI: Smart and compact 3D printer

#103

Post by jrockway » Sun, Oct 13, 2019, 4:47 AM UTC

dfasdfasd wrote: post #74

jrockway wrote: post #50

Earlier quoted context omitted.

The price seems fine to me. This is going to print a lot of useful parts for people and comes with great software for both your computer and the printer that you can hack and modify. If this is anything like my i3, then it's going to have high quality parts (Noctua fans!) and come in kit form to let you assemble it yourself so you know where everything is if something breaks and you need to repair it. I am surprised…

> While it is something Reddit endlessly complains about (despite having no software engineering experience) While I agree Reddit's obsession with weird technical details is annoying, this is a pretty arrogant position. I've written motion control code for both 8-bit and 32-bit designs, and the difference is bigger than "read a string and pulse an IO a few times". The Atmega has been outdated for the past 10 years, t…

Sure, but now they are a small company that has to maintain two separate codebases. Even big companies like Google can't keep their Android and iOS apps at feature parity, so something has to give and it's the early adopters with old hardware that is just not going to get any new features. Or they are going to have twice the software engineering overhead.

I get why you would start from scratch with an M4. I don't get why you would maintain two different codebases commercially, though.

(As for the motion control aspect, at the feedrates of 3D printers, I don't think you get anything from a faster processor. Motion control is not what's limiting print speed or accuracy.)

Re: Prusa MINI: Smart and compact 3D printer

#104

Post by ex3ndr » Sun, Oct 13, 2019, 5:14 AM UTC

monkmartinez wrote: post #2

I don't like it for a few reasons; 1. It looks like you are going to fight "ringing" with lack of rigidity. 2. Its a bowden extruder... which I suppose is a necessity due to the lack of structure. Still I would rather have direct drive on every machine. 3. It's very expensive. You can buy an Ender for $200 or less on sale... or around $230 normal price. Upgrade the board to a 32bit Bigtreetech for $60 with Trinamic d…

Isn't they have SLS machine?

Re: Prusa MINI: Smart and compact 3D printer

#105

Post by tumes » Sun, Oct 13, 2019, 6:14 AM UTC

alphagrep12345 wrote: post #17

Why does everyone need a 3d printer? Maybe this statement would sound as ludicrous looking back as asking why does everyone need a PC in the 1980s. However, I still don't understand why would a regular person need a 3d printer? Mass marketed goods are always cheaper due to economies of scale. And would you really want to put in the effort to make your own chair, etc?

This will sound frivolous and ridiculous, but I have a toddler with constantly changing tastes and it's a nice way to be able to engage with and encourage their interests. For example, cars have been a huge deal lately, and being able to 1) print a bunch of logos for room decorations and 2) put the logos in areas that the kiddo finds onerous to encourage them to go there (e.g. How many cars can you name while we get changed for preschool) has been a life saver.

Plus it's nice to be the hero around the house when I can solve random maintenance problems with a quick search on Thingiverse or a couple of hours of designing and printing. Not sure it has literally paid for itself since I got one, but it has definitely be more useful than I expected and I would say it has been borderline indispensable for my household.

Re: Prusa MINI: Smart and compact 3D printer

#106

Post by tumes » Sun, Oct 13, 2019, 6:19 AM UTC

dwoozle wrote: post #21

alphagrep12345 wrote: post #17

Why does everyone need a 3d printer? Maybe this statement would sound as ludicrous looking back as asking why does everyone need a PC in the 1980s. However, I still don't understand why would a regular person need a 3d printer? Mass marketed goods are always cheaper due to economies of scale. And would you really want to put in the effort to make your own chair, etc?

I print a lot of stuff around the house with a toddler. I printed guards to prevent him from turning on the oven, a insert for the piano that prevents him from pressing the auto play demo, a shim to get a drawer to close more smoothly, a shampoo caddy that hooks around our shower stall, a storage system for small hardware, a set of clips for the computer cords to keep them organized, a doohickey to strip leaves off o…

Ha, I thought I was being novel pointing out how convenient it was for solving the myriad problems that come with parenthood. I printed a bunch of car logos for my vehicle-obsessed kid to stare at, name, and futz with during diaper changing time and it has figuratively paid for itself in terms of mitigating piddling power struggles.

Plus I cannot express the collective relief my spouse and I felt when I was able to repair a poorly designed part on the malfunctioning coffee maker in an hour's time. We're solving the real problems here.

Re: Prusa MINI: Smart and compact 3D printer

#107

Post by Arcanum-XIII » Sun, Oct 13, 2019, 6:50 AM UTC

drudru11 wrote: post #56

j-pb wrote: post #8

I'm glad that prusa has stayed true to his open hardware pledge all these years, while continuing to push the reprap ideals. Everybody is complaining about the price, but c'mon this thing is designed printed and assembled in Prague, the EU. It creates local jobs for people with fair wages, social security and good quality of life, we should strive to have more of our stuff produced in the west. Happy to see him desig…

Price seems totally reasonable to me. Whenever I research the cheaper printers, I read about all the upgrades people have to implement. This ends up costing more time and $$.

Can’t agree more. I bought a Creality Ender 3, and added since: a new bed plate, a leveling sensor, a raspberry pi to control it

For the future, I know I’ll replace the fans, and probably the main board

That’s without adding my time: updating the firmware (overheating protection seems cool), calibrating and configuration of the various bit (like the probe position relative to the hot end), finding the correct slicer and config for it.

Now it works fine.

Still, it cost me way more than the list price to get to this point. A prusa mini would have been a better investment !

Re: Prusa MINI: Smart and compact 3D printer

#108

Post by IshKebab » Sun, Oct 13, 2019, 6:53 AM UTC

jrockway wrote: post #48

m0xte wrote: post #45

Earlier quoted context omitted.

Note: former EE. I’ve taken it and the provided power supply to bits before I even fired it up. 1. They’re IRLR3103PBF operated within their SOA. They’re fine. Most MOSFETs fail short due to the construction of the MOSFET. I’ve actually got a few scars on my arms from the buggers exploding on me misusing them on purpose as RF PA’s as a ham. I’ve seen them blow up in various bits of expensive US made kit too (tektroni…

I think he is referring to a step motor controller as a "stepper". People love the fact that Prusa uses Trinamic drivers instead of no-name drivers. I personally don't understand why step motor control is something that needs to be outsourced. Just stick an H-bridge between the microcontroller and the motor and improve the control algorithm with every release.

I've done manual h-bridge style control and it just can't match a proper driver. You're going to get a ton more vibration and less power.

I use Leadshine ones normally. They're big but also very reasonably priced and work very well.

Re: Prusa MINI: Smart and compact 3D printer

#109

Post by thrax » Sun, Oct 13, 2019, 6:54 AM UTC

alphagrep12345 wrote: post #17

Why does everyone need a 3d printer? Maybe this statement would sound as ludicrous looking back as asking why does everyone need a PC in the 1980s. However, I still don't understand why would a regular person need a 3d printer? Mass marketed goods are always cheaper due to economies of scale. And would you really want to put in the effort to make your own chair, etc?

I use mine for designing and building robot parts. I can design, print, and test like 5 different component designs per day. The difference this makes in quality of construction is insane. Even if I had a full tool tool shop I wouldn't be able to iterate like this. It's truly incredible.

Re: Prusa MINI: Smart and compact 3D printer

#110

Post by ekr » Sun, Oct 13, 2019, 7:09 AM UTC

j-pb wrote: post #8

I'm glad that prusa has stayed true to his open hardware pledge all these years, while continuing to push the reprap ideals. Everybody is complaining about the price, but c'mon this thing is designed printed and assembled in Prague, the EU. It creates local jobs for people with fair wages, social security and good quality of life, we should strive to have more of our stuff produced in the west. Happy to see him desig…

> It creates local jobs for people with fair wages, social security and good quality of life, we should strive to have more of our stuff produced in the west.

I don't really agree with that argument from a humanitarian perspective. That would simply further increase the vast economic inequality between the west and the rest. Even with lower wages, people in China are better off with more jobs than fewer. People in the Czech Republic for instance have more safety nets, more alternatives and opportunities.