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Problem with 3D printing is how slow it really is. I do see a path for better printing quality and overtime becoming indistinguishable from injection molding, b

Problem with 3D printing is how slow it really is. I do see a path for better printing quality and overtime becoming indistinguishable from injection molding, but I do not see any path for beating a 15 second cycle time. Printing a coffee mug can take whopping 8 hours, depending on specifics of quality and the machine. I feel like Injection Molding is far more amazing, interesting, intriguing and challenging process than 3D printing and yet, it gets zero media coverage. Before people respond to this - yes, I know the pros/cons of 3D printing and it certainly has place in manufacturing processes. Just pointing out the media hype around 3D printing which I thought would die down after 2015 or so... but it continues to overwhelm news sources. Edit: Goddamn it HN, why are you all responding to the pros/cons of 3D printing? My complain is about media coverage and how click baity engagement metrics propelled 3D printing into this glorified do-all-world-changing-technology. It disproportionately gets attention, was just using injection-molding as a talking point. There are so many interesting manufacturing techniques. Every MBA exec wants their engineers to explore 3D-printing without knowing its downsides, thanks to the stupid media.

sfifs 6y ago
As with nearly all capabilities in all fields, you're trading off flexibility, quality, throughput and speed to market. You're also trading off cost on the vectors of capex vs. opex. Injection moulding gives high quality and throughput with low flexibility and relatively high capex. That makes it fit for use for some cases and not for others. In my home 3d printer for instance, i can download and print a snowflake or some small toy my child wants to hang on the Christmas tree that she is missing in about 20 mins which otherwise would entail a trip to the store or ordering online and waiting. However, if i were to print all the decorations she wants to hang, it would take an inordinate amount of time and I'm better off making the trip to the store.
notRobot 6y ago
Injection molding is established technology and nothing new, and is much harder to DIY, which is why it gets less media coverage. The beauty of 3D printing is that you need no molds. You can print all sorts of stuff with the same printer in the same config.
- systemvoltage 6y ago
  You nailed it. The problem now is that every exec wants their engineers to investigate 3D printing even if it makes zero sense because of all the media hype in last decade.
avmich 6y ago
> Problem with 3D printing is how slow it really is. I think 3D printing is a really scalable approach. You can have a large 3D printer with tens or maybe much more printing heads, all working in parallel on the same large part or the whole product.
- mxcrossb 6y ago
  The benefit of 3D printing is flexibility. If you’re going to print at scale to make up for time, you’ve left the realm of flexibility and are now in the world of mass production.
  - jacquesm 6y ago
    Not necessarily. You could have many printheads side-by-side leaving you still very general in terms of what you can do but much faster.
    - systemvoltage 6y ago
      Nevermind energy consumption, floor space, maintenance, inconsistency in quality, loading-unloading times, postprocessing / cleaning, etc. 3D printing is not really scalable. Folks that suggest we can just buy 10,000 3D printers to replace 8 injection molding machines haven't really stepped into a high volume factory, much less operate one.
      - jacquesm 6y ago
        Energy consumption of other manufacturing methods is also quite high, for instance, injection molding is super energy intensive, as are most forms of casting and machining. It's clear that 3D printing is no substitute for injection molding, stamping or or other such mass fabrication methods. But, like with every other manufacturing method: it is complementary, there are applications for all of these. And yes, I've stepped into factories, and worked with/for them, beside that I had a metal workshop and was partner in an early CAD/CAM company. So FWIW I think I understand the limitations of the tech quite well, and I think that if 3D printing could be sped up by a factor of 100 or so (which is definitely in the realm of the possible) that the other disadvantages would matter a lot less than they do today.
ipsum2 6y ago
Maybe this is too off topic, but I've always wondered why injection molding couldn't be done cheaper (albeit slower) by just milling aluminum to be used as molds. Why is there such a large gap between 3d printing something and setting up an expensive ($50k+) and time consuming (months) injection molding station?
- petertodd 6y ago
  Aluminum is used for injection molds: https://www.protolabs.com/resources/blog/injection-molding-aluminum-vs-steel-tooling/ https://www.protolabs.com/resources/blog/injection-molding-a... https://www.moldmakingtechnology.com/articles/lets-be-clear-about-aluminum https://www.moldmakingtechnology.com/articles/lets-be-clear-... tl;dr: the molds aren't as durable, and can't do certain things as well as steel molds can. But for small volumes and simpler designs that doesn't matter, so they are quite commonly used.
  - atupis 6y ago
    Next logical step is 3d-print those Aluminum molds.
    - s1artibartfast 6y ago
      Why? CNC machining provides better quality and is faster. You can CNC a simple mold in minutes with precision that exceeds any 3D printing technology.
      - VBprogrammer 6y ago
        One possible reason would be to allow geometry which isn't easily milled. Perhaps cooling jackets, for example, could be incorporated into the mold for example.
        avianlyric 6y ago
        Beyond the cooling jackets there isn’t really going to be anything hard to mill. If the geometry is hard to mill, then it’s almost certainly inappropriate for injection moulding (assuming you actually want to extract your injection moulded object from the mould).
onion2k 6y ago
Problem with 3D printing is how slow it really is. I think you need to start thinking about manufacturing as more than just the mass production of identical products. 3D printing isn't at all suitable if you want to make 10,000 identical items. That doesn't make it useless.
- systemvoltage 6y ago
  I didn't say it is useless.
- Frenchgeek 6y ago
  We do get 3D printed parts from time to time at work: They usually need to have brass inserts put in them, which mean milling the printed holes to size too. Since the part is fairly complex, milling the part wouldn't be that much of a time saver. I'd say 5~7 hours print-job on each, depending on the printer, milling it could be done in half that easily, but a qualified operator's time cost a fair bit more than someone keeping an eye on two (or more) printers while doing paperwork. (As long as they don't need more than the ten pieces we get (at most) at a time at least.)
numpad0 6y ago
Give me a $399 Chinese injection molding gear copied from an open source design by a guy in Europe -- I mean, that's how 3D printing culture started, but the FDM printer technology itself did exist and were used, albeit at small scales in professional contexts, just like how industrial injection molding exists right now.
- jononor 6y ago
  Would by immediately for our makerspace - where we already have CNC machines that we can make alu molds with.
knaq 6y ago
It wouldn't have to be slow. Print on the inside of a spinning drum. That way, you don't have to reverse direction. Print from a whole row of nozzles or lasers or whatever. That way, yet another dimension doesn't require reversing movement. That leaves just one axis if laying something down like an inkjet printer. If curing with a laser, the final axis can be handled by the laser simply crossing the needed distance.
jacquesm 6y ago
The revolution will be when we can use 1000's of printheads in parallel. I don't think that's SF, more of an engineering problem. A bit like a 'dot matrix' printer for PLA.
arminiusreturns 6y ago
I've been really interested for a while now in titanium, and while I think laser sintering is a really cool application, something caught my eye when trying to find videos about the material: some of the titanium-alloy hammers you can buy at the hardware store are made by molten metal casting in ceramic molds. For some reason it really fascinates me to see titanium being used that way, because it's not the way most places use it (it is a notoriously hard metal to work with). I wonder, are laser sintering and other techniques fundamentally slow or can they be improved to be more competitive? https://youtu.be/p1Vk2hMO0ME?t=83 https://youtu.be/p1Vk2hMO0ME?t=83
- lylecheatham 6y ago
  They are pretty fundamentally slow because of the constraints from the melt pool. Because you are trying to locally melt the material (lots of energy) and then immediately solidify it, you pretty much have to use a melt pool under a certain size and go under a certain speed to avoid making a total mess of the part. Also a significant amount of energy goes to waste as it gets dissipated by the material, and the powder feedstock is extremely expensive as it needs to be a certain size of round powder which is hard to manufacture.
imtringued 6y ago
>I feel like Injection Molding is far more amazing, interesting, intriguing and challenging process than 3D printing and yet, it gets zero media coverage. The cheapest desktop injection molding machine [0] I have seen costs $12500 and it's not very capable. Yeah sure it is intriguing and interesting and challenging just like a $200k CNC machine is interesting but how can you be surprised that there is no community of "home gamers" with these machines? The real injection molding machines are huge, bloody expensive and most of them have been moved to China. Just look at the size of the final products: https://youtu.be/n7JWPxk92fY?t=857 https://youtu.be/n7JWPxk92fY?t=857 There are also lots of quality problems because injection molding is a process where you have to mess around with the settings and do multiple production runs before you figure out how to get optimal results. Your 3D printer is slow but reliable in comparison. You have very high confidence that once you tune the printer itself (not the specific injection molding production run) the vast majority of your prints will succeed on first print without you having to do anything. This means you can easily produce one off parts at low cost. It's easy to see why 3D printing is popular. It's cheap and just works both in terms of reliability and the size of the objects you can make. Meanwhile with injection molding that $12500 machine is barely capable of anything a hobbyist would want and that's without considering that you need to design your own molds and then machine them yourself because if you are going to outsource the mold you might as well outsource everything and who wants to make an article about "hey you can contact these companies to produce injection molded parts"? Everyone already knows that this is something companies do. [0] https://www.apsx.com/desktop-injection-molding-machine https://www.apsx.com/desktop-injection-molding-machine
- s1artibartfast 6y ago
  I think you two are making two compatible points: 1) Injection Molding is far more amazing, interesting, intriguing and challenging 2) There is wider market for home 3D printing than injection molding It really comes down to what you are trying to do and what you need your parts for. Also, there absolute is a community of home machinists. I have met a couple people with home CNCs, and many more with very capable machine shops.
  - Gravityloss 6y ago
rstuart4133 6y ago
> Problem with 3D printing is how slow it really is. Yeh, it's slow. But the article is talking about "The ability to build a one-off product such as a boat or small yacht, directly from CAD". I dunno about you, but I've designed and paid for injection molds, and there is nothing cheap or fast about producing the first one. We were a small company, those molds cost us a substantial fraction of our capital. I would not describe the feelings engendered by unpacking and checking that first one as magical. Words that spring to mind are hope and dread, and eventually relief when we realised it would not be that expensive to move through holes in PCB's by 0.5mm, and adjust metal jigs, and resignation that the aesthetics of the thing were not quite as we expected, but would do. Now a technology that allowed us to print something in 24 or 48 hours for a few thousand that was actually useable in the field - that would have looked absolutely magical. Being able to print something size of a boat hull that is strong enough to sail is almost unbelievable, even now.
- notahacker 6y ago
  The more interesting comparison point might be other CNC machining techniques which share the ability to create one off products directly from CAD with raw material, but seem to get a fraction of the attention of 'printing'. Leaving aside them being less suited to some use cases than 'printing' (and much more suited to others), is computer controlled manufacturing using an additive process really that much more magical than computer controlled manufacturing using a subtractive process?
  - jstanley 6y ago
    You'd be throwing an awful lot of material away if you tried to machine a boat out of a solid block of plastic. Subtractive manufacturing can give you a higher-quality result and can use a wider range of materials, but the machinery costs more because it needs to be stronger, and the materials cost more because you throw away everything that doesn't go into the final part.
    - reitzensteinm 6y ago
      Surely if you do it at scale the removed material can be recycled fairly cheaply?
baxtr 6y ago
I think you make an excellent meta point. I would love to know why this happens. Why are some technology super hyped and others aren't? Maybe it is a stochastic process and somehow one term gets amplified and gets the attention of the MBAs and consultants. Dunno. Love to hear some theories
- dmurray 6y ago
  I don't think it's just a random process. The coolest-sounding technologies are the ones where you can describe to a layman how it works, but they've still rarely or never seen something that works that way. 3d-printing is perfect tech for this: the principle is graspable by anyone, it makes for cool stop motion videos, yet it's still rare in practice. Injection moulding is too commonplace: we've cast metal in moulds for thousands of years. A cool name helps as well, of course. 3D printing is definitely sexier than "additive manufacturing".
- 2muchcoffeeman 6y ago
  In this case I think it’s obvious if you know the pros and cons of 3D printing. 3D printing has a major pro: It may be slow to make 1 thing, but I can make anything I want change it quickly. I got a 3D printer a couple years ago. It’s pretty amazing. I can recreate broken parts, design improvements to existing things and prototype them without any help. These days with so much emphasis on reducing our environmental footprint, why would be interested in mass production?
- saberdancer 6y ago
  3d printing is hyped because you can get a 3D printer at home and have fun prototyping. Injection molding is a industrial process and isn't really accessible to people.
- blihp 6y ago
  It's usually a function of how much time/energy/money companies in a space put into generating the hype. There are teams of people at the better funded companies working to arrange interviews, plant stories, have influencers promote things and so on... all in an attempt to build awareness and eventually help them increase sales. It's basically an early stage marketing strategy until it's known how big the market is and how big a piece of it a given company is able to get and then more traditional marketing approaches take over. Worst case: the company runs out of money which will also turn off the hype machine.
hyperpallium2 6y ago
Isn't it getting exponentially cheaper and faster? That's newsworthy.
blihp 6y ago
In some applications the turnaround time either doesn't matter or can be overcome. (i.e. with FDM printing it's pretty trivial to use 2..N print heads to get an increase of 2..N in part production) Also, this happens with virtually every new technology. See AI, blockchain etc. In every company that a given technology potentially impacts/applies to, at some point there is an Executive asking 'what is our strategy for X?' which results in one or more projects related to X being spun up. Eventually most of these efforts will fizzle/fade but there will be a subset of use cases where there will be a (possibly surprising) benefit that offsets the slow speed / limited resolution / whatever that makes 3D printing worth using in real production environments. There are also some instances where 3D printing (whether FDM, SLA, SLS etc) can produce a better result than existing alternatives like injection molding. It's just another tool in the toolbox.
- StavrosK 6y ago
  > In some applications the turnaround time either doesn't matter or can be overcome. (i.e. with FDM printing it's pretty trivial to use 2..N print heads to get an increase of 2..N in part production) Not if you only need one, which is true for the vast majority of prints.
avianlyric 6y ago
> My complain is about media coverage and how click baity engagement metrics propelled 3D printing into this glorified do-all-world-changing-technology. I do think this is a surprise, injection moulding is a technique as old as dirt (well really plastic). You wanna see crazy coverage for injection moulding go back to the 1910s when the technique was starting to take off. At the end of the day there just aren’t any big innovations in injection moulding to talk about, it all minor process improvements, may of which are happening behind closed doors, hidden as company secret sauce. 3D printing on the other hand. Is such an comparatively underdeveloped and under-utilised technique that just sneezing next to a 3D printer is a form of news worth innovation.
wolfretcrap 6y ago
Raw material for 3d printing is ultra cheap specially when you try making your own filament from plastic pellets which sell for dirt cheap: https://medium.com/endless-filament/make-your-filament-at-home-for-cheap-6c908bb09922 https://medium.com/endless-filament/make-your-filament-at-ho...
mrlala 6y ago
Um why would there need to be 'media coverage' around technologies that everyone knows about and has basically been around forever? Media coverage dominates new technology [3d printing]... SHOCKER I TELL YOU!
meragrin_ 6y ago
> Edit: Goddamn it HN, why are you all responding to the pros/cons of 3D printing? Your complaint about media coverage was a whole sentence. Sentence and a half being generous. The complaint itself looks like a related comment at the end rather than the main point. Most of your post was pros/cons which was not clearly linked to media coverage. It really does look like a post about injection molding vs 3d printing.
ehnto 6y ago
I wonder if you had put your paragraphs in the other order, you might have had better luck. I was absolutely about to reply with some discussion on 3D printing, until I noticed the edit keyword and so read that first. I know it should be on the reader to fully read a comment, but it's the internet, so I adjust my comments sometimes to make sure my point is across before people jump ship.
Wowfunhappy 6y ago
> Edit: Goddamn it HN, why are you all responding to the pros/cons of 3D printing? My complain is about media coverage Because the appropriateness of rosy media coverage is dependent on the actual potential of 3D printing.
detaro 6y ago
For media coverage, does injection molding have flashy new use cases etc? My (non-expert) impression is that injection molding is the "boring default" for many use cases, and thus improvement in it won't see much coverage. (+ the specific submission is on a website specializing on 3D printing as a topic). If you show me an industrially made part and say "they injection molded that", the reaction is "sure, as you would", not "Oh? that's interesting, why did they do that?". Similar to how news will rather report on unusual building materials rather than run stories to remind people that bricks are cool too. (and if a home buyer insists on using something fancy new over bricks or whatever default would be more appropriate, that's their fault) That's not to say that defaults actually are boring if you deal with them directly, I find people explaining details of things like injection molding fascinating, but "we improved X in a standard industry process" just isn't as easy to make briefly interesting to mass audience and thus gets reported less.
- lylecheatham 6y ago
  Apple actually gets a decent amount of coverage for their very impressive injection moldings. Most advancements in IM today are not in the ability to make complex parts, but more in the ability to make them pretty. Apple makes many parts with extremely tight tolerances with almost no visual defects, and within the industry it's understood that it's extremely hard to make your IM parts look like Apple's for that reason.
  - detaro 6y ago
    Yes, even mainstream media covers that every now and then (e.g. "Apple just bought an entire company making X to make even better macbooks/iPhones/..."), but as the parent poster complained 3D printing is getting more attention. Whereas "within the industry" is exactly the thing I'm talking about: the threshold for getting into more mainstream media is not necessarily related to actual importance and different from what field-specific or even just enthusiast perception focuses on. E.g. the bits and pieces I know about injection molding mostly come from "maker-type" publications that, while of course also talking about 3D printing a lot, also cover entry-level discussions of what happens if you try taking something to larger-scale production - and "forget about your product looking like an Apple product" is high on that list ;)
dfischer 6y ago
This kinda misses the point of the core. 3D printing transfers power inward vs outward. When this happens innovation explodes as the average individual has much more ability to produce on their own. Localized manufacturing is a subtle huge boom similar to computation.
panabee 6y ago
thanks for the comment. what are some other manufacturing techniques you think warrant more attention and research?
salt-licker 6y ago
This is an excellent point. 3D printing will likely never replace injection molding for plastic parts above a volume of a few thousand. This is well known in the industry but largely unexamined by the media. High-strength 3D printing however, of composites / metal, has a much higher market ceiling. Can certainly be cost-competitive with CNC and probably also expendable mold casting in the short-term.
snarfy 6y ago
The real money is selling large format 3D printers. For what they are they sure cost a premium.
rajnathani 6y ago
All these boats getting 3D printed (also those mentioned in the article) are made from composites, primarily carbon fiber or fiberglass based composites. Injection molding for plastic parts is easy and fast, however the current process it takes to make carbon fiber composites is highly energy intensive (one needs huge ovens), time consuming, expensive, and some approaches can even be highly labor intensive. This is also the reason why only the more expensive cars in the market have carbon fiber bodies as opposed to all cars/vehicles in the market. An example of the process of carbon fiber construction today from Koenigsegg's cars: https://www.youtube.com/watch?v=504I_hJDFck https://www.youtube.com/watch?v=504I_hJDFck

sfifs 6y ago

As with nearly all capabilities in all fields, you're trading off flexibility, quality, throughput and speed to market. You're also trading off cost on the vectors of capex vs. opex. Injection moulding gives high quality and throughput with low flexibility and relatively high capex. That makes it fit for use for some cases and not for others. In my home 3d printer for instance, i can download and print a snowflake or some small toy my child wants to hang on the Christmas tree that she is missing in about 20 mins which otherwise would entail a trip to the store or ordering online and waiting. However, if i were to print all the decorations she wants to hang, it would take an inordinate amount of time and I'm better off making the trip to the store.

notRobot 6y ago

Injection molding is established technology and nothing new, and is much harder to DIY, which is why it gets less media coverage. The beauty of 3D printing is that you need no molds. You can print all sorts of stuff with the same printer in the same config.

systemvoltage 6y ago
You nailed it. The problem now is that every exec wants their engineers to investigate 3D printing even if it makes zero sense because of all the media hype in last decade.

avmich 6y ago

> Problem with 3D printing is how slow it really is. I think 3D printing is a really scalable approach. You can have a large 3D printer with tens or maybe much more printing heads, all working in parallel on the same large part or the whole product.

mxcrossb 6y ago
The benefit of 3D printing is flexibility. If you’re going to print at scale to make up for time, you’ve left the realm of flexibility and are now in the world of mass production.
- jacquesm 6y ago
  Not necessarily. You could have many printheads side-by-side leaving you still very general in terms of what you can do but much faster.
  - systemvoltage 6y ago
    Nevermind energy consumption, floor space, maintenance, inconsistency in quality, loading-unloading times, postprocessing / cleaning, etc. 3D printing is not really scalable. Folks that suggest we can just buy 10,000 3D printers to replace 8 injection molding machines haven't really stepped into a high volume factory, much less operate one.
    - jacquesm 6y ago
      Energy consumption of other manufacturing methods is also quite high, for instance, injection molding is super energy intensive, as are most forms of casting and machining. It's clear that 3D printing is no substitute for injection molding, stamping or or other such mass fabrication methods. But, like with every other manufacturing method: it is complementary, there are applications for all of these. And yes, I've stepped into factories, and worked with/for them, beside that I had a metal workshop and was partner in an early CAD/CAM company. So FWIW I think I understand the limitations of the tech quite well, and I think that if 3D printing could be sped up by a factor of 100 or so (which is definitely in the realm of the possible) that the other disadvantages would matter a lot less than they do today.

ipsum2 6y ago

Maybe this is too off topic, but I've always wondered why injection molding couldn't be done cheaper (albeit slower) by just milling aluminum to be used as molds. Why is there such a large gap between 3d printing something and setting up an expensive ($50k+) and time consuming (months) injection molding station?

petertodd 6y ago
Aluminum is used for injection molds: https://www.protolabs.com/resources/blog/injection-molding-aluminum-vs-steel-tooling/ https://www.protolabs.com/resources/blog/injection-molding-a... https://www.moldmakingtechnology.com/articles/lets-be-clear-about-aluminum https://www.moldmakingtechnology.com/articles/lets-be-clear-... tl;dr: the molds aren't as durable, and can't do certain things as well as steel molds can. But for small volumes and simpler designs that doesn't matter, so they are quite commonly used.
- atupis 6y ago
  Next logical step is 3d-print those Aluminum molds.
  - s1artibartfast 6y ago
    Why? CNC machining provides better quality and is faster. You can CNC a simple mold in minutes with precision that exceeds any 3D printing technology.
    - VBprogrammer 6y ago
      One possible reason would be to allow geometry which isn't easily milled. Perhaps cooling jackets, for example, could be incorporated into the mold for example.
      - avianlyric 6y ago
        Beyond the cooling jackets there isn’t really going to be anything hard to mill. If the geometry is hard to mill, then it’s almost certainly inappropriate for injection moulding (assuming you actually want to extract your injection moulded object from the mould).

onion2k 6y ago

Problem with 3D printing is how slow it really is. I think you need to start thinking about manufacturing as more than just the mass production of identical products. 3D printing isn't at all suitable if you want to make 10,000 identical items. That doesn't make it useless.

systemvoltage 6y ago
I didn't say it is useless.
Frenchgeek 6y ago
We do get 3D printed parts from time to time at work: They usually need to have brass inserts put in them, which mean milling the printed holes to size too. Since the part is fairly complex, milling the part wouldn't be that much of a time saver. I'd say 5~7 hours print-job on each, depending on the printer, milling it could be done in half that easily, but a qualified operator's time cost a fair bit more than someone keeping an eye on two (or more) printers while doing paperwork. (As long as they don't need more than the ten pieces we get (at most) at a time at least.)

numpad0 6y ago

Give me a $399 Chinese injection molding gear copied from an open source design by a guy in Europe -- I mean, that's how 3D printing culture started, but the FDM printer technology itself did exist and were used, albeit at small scales in professional contexts, just like how industrial injection molding exists right now.

jononor 6y ago
Would by immediately for our makerspace - where we already have CNC machines that we can make alu molds with.

knaq 6y ago

It wouldn't have to be slow. Print on the inside of a spinning drum. That way, you don't have to reverse direction. Print from a whole row of nozzles or lasers or whatever. That way, yet another dimension doesn't require reversing movement. That leaves just one axis if laying something down like an inkjet printer. If curing with a laser, the final axis can be handled by the laser simply crossing the needed distance.

jacquesm 6y ago

The revolution will be when we can use 1000's of printheads in parallel. I don't think that's SF, more of an engineering problem. A bit like a 'dot matrix' printer for PLA.

arminiusreturns 6y ago

I've been really interested for a while now in titanium, and while I think laser sintering is a really cool application, something caught my eye when trying to find videos about the material: some of the titanium-alloy hammers you can buy at the hardware store are made by molten metal casting in ceramic molds. For some reason it really fascinates me to see titanium being used that way, because it's not the way most places use it (it is a notoriously hard metal to work with). I wonder, are laser sintering and other techniques fundamentally slow or can they be improved to be more competitive? https://youtu.be/p1Vk2hMO0ME?t=83 https://youtu.be/p1Vk2hMO0ME?t=83

lylecheatham 6y ago
They are pretty fundamentally slow because of the constraints from the melt pool. Because you are trying to locally melt the material (lots of energy) and then immediately solidify it, you pretty much have to use a melt pool under a certain size and go under a certain speed to avoid making a total mess of the part. Also a significant amount of energy goes to waste as it gets dissipated by the material, and the powder feedstock is extremely expensive as it needs to be a certain size of round powder which is hard to manufacture.

imtringued 6y ago

>I feel like Injection Molding is far more amazing, interesting, intriguing and challenging process than 3D printing and yet, it gets zero media coverage. The cheapest desktop injection molding machine [0] I have seen costs $12500 and it's not very capable. Yeah sure it is intriguing and interesting and challenging just like a $200k CNC machine is interesting but how can you be surprised that there is no community of "home gamers" with these machines? The real injection molding machines are huge, bloody expensive and most of them have been moved to China. Just look at the size of the final products: https://youtu.be/n7JWPxk92fY?t=857 https://youtu.be/n7JWPxk92fY?t=857 There are also lots of quality problems because injection molding is a process where you have to mess around with the settings and do multiple production runs before you figure out how to get optimal results. Your 3D printer is slow but reliable in comparison. You have very high confidence that once you tune the printer itself (not the specific injection molding production run) the vast majority of your prints will succeed on first print without you having to do anything. This means you can easily produce one off parts at low cost. It's easy to see why 3D printing is popular. It's cheap and just works both in terms of reliability and the size of the objects you can make. Meanwhile with injection molding that $12500 machine is barely capable of anything a hobbyist would want and that's without considering that you need to design your own molds and then machine them yourself because if you are going to outsource the mold you might as well outsource everything and who wants to make an article about "hey you can contact these companies to produce injection molded parts"? Everyone already knows that this is something companies do. [0] https://www.apsx.com/desktop-injection-molding-machine https://www.apsx.com/desktop-injection-molding-machine

s1artibartfast 6y ago
I think you two are making two compatible points: 1) Injection Molding is far more amazing, interesting, intriguing and challenging 2) There is wider market for home 3D printing than injection molding It really comes down to what you are trying to do and what you need your parts for. Also, there absolute is a community of home machinists. I have met a couple people with home CNCs, and many more with very capable machine shops.
- Gravityloss 6y ago

rstuart4133 6y ago

> Problem with 3D printing is how slow it really is. Yeh, it's slow. But the article is talking about "The ability to build a one-off product such as a boat or small yacht, directly from CAD". I dunno about you, but I've designed and paid for injection molds, and there is nothing cheap or fast about producing the first one. We were a small company, those molds cost us a substantial fraction of our capital. I would not describe the feelings engendered by unpacking and checking that first one as magical. Words that spring to mind are hope and dread, and eventually relief when we realised it would not be that expensive to move through holes in PCB's by 0.5mm, and adjust metal jigs, and resignation that the aesthetics of the thing were not quite as we expected, but would do. Now a technology that allowed us to print something in 24 or 48 hours for a few thousand that was actually useable in the field - that would have looked absolutely magical. Being able to print something size of a boat hull that is strong enough to sail is almost unbelievable, even now.

notahacker 6y ago
The more interesting comparison point might be other CNC machining techniques which share the ability to create one off products directly from CAD with raw material, but seem to get a fraction of the attention of 'printing'. Leaving aside them being less suited to some use cases than 'printing' (and much more suited to others), is computer controlled manufacturing using an additive process really that much more magical than computer controlled manufacturing using a subtractive process?
- jstanley 6y ago
  You'd be throwing an awful lot of material away if you tried to machine a boat out of a solid block of plastic. Subtractive manufacturing can give you a higher-quality result and can use a wider range of materials, but the machinery costs more because it needs to be stronger, and the materials cost more because you throw away everything that doesn't go into the final part.
  - reitzensteinm 6y ago
    Surely if you do it at scale the removed material can be recycled fairly cheaply?

baxtr 6y ago

I think you make an excellent meta point. I would love to know why this happens. Why are some technology super hyped and others aren't? Maybe it is a stochastic process and somehow one term gets amplified and gets the attention of the MBAs and consultants. Dunno. Love to hear some theories

dmurray 6y ago
I don't think it's just a random process. The coolest-sounding technologies are the ones where you can describe to a layman how it works, but they've still rarely or never seen something that works that way. 3d-printing is perfect tech for this: the principle is graspable by anyone, it makes for cool stop motion videos, yet it's still rare in practice. Injection moulding is too commonplace: we've cast metal in moulds for thousands of years. A cool name helps as well, of course. 3D printing is definitely sexier than "additive manufacturing".
2muchcoffeeman 6y ago
In this case I think it’s obvious if you know the pros and cons of 3D printing. 3D printing has a major pro: It may be slow to make 1 thing, but I can make anything I want change it quickly. I got a 3D printer a couple years ago. It’s pretty amazing. I can recreate broken parts, design improvements to existing things and prototype them without any help. These days with so much emphasis on reducing our environmental footprint, why would be interested in mass production?
saberdancer 6y ago
3d printing is hyped because you can get a 3D printer at home and have fun prototyping. Injection molding is a industrial process and isn't really accessible to people.
blihp 6y ago
It's usually a function of how much time/energy/money companies in a space put into generating the hype. There are teams of people at the better funded companies working to arrange interviews, plant stories, have influencers promote things and so on... all in an attempt to build awareness and eventually help them increase sales. It's basically an early stage marketing strategy until it's known how big the market is and how big a piece of it a given company is able to get and then more traditional marketing approaches take over. Worst case: the company runs out of money which will also turn off the hype machine.

hyperpallium2 6y ago

Isn't it getting exponentially cheaper and faster? That's newsworthy.

blihp 6y ago

In some applications the turnaround time either doesn't matter or can be overcome. (i.e. with FDM printing it's pretty trivial to use 2..N print heads to get an increase of 2..N in part production) Also, this happens with virtually every new technology. See AI, blockchain etc. In every company that a given technology potentially impacts/applies to, at some point there is an Executive asking 'what is our strategy for X?' which results in one or more projects related to X being spun up. Eventually most of these efforts will fizzle/fade but there will be a subset of use cases where there will be a (possibly surprising) benefit that offsets the slow speed / limited resolution / whatever that makes 3D printing worth using in real production environments. There are also some instances where 3D printing (whether FDM, SLA, SLS etc) can produce a better result than existing alternatives like injection molding. It's just another tool in the toolbox.

StavrosK 6y ago
> In some applications the turnaround time either doesn't matter or can be overcome. (i.e. with FDM printing it's pretty trivial to use 2..N print heads to get an increase of 2..N in part production) Not if you only need one, which is true for the vast majority of prints.

avianlyric 6y ago

> My complain is about media coverage and how click baity engagement metrics propelled 3D printing into this glorified do-all-world-changing-technology. I do think this is a surprise, injection moulding is a technique as old as dirt (well really plastic). You wanna see crazy coverage for injection moulding go back to the 1910s when the technique was starting to take off. At the end of the day there just aren’t any big innovations in injection moulding to talk about, it all minor process improvements, may of which are happening behind closed doors, hidden as company secret sauce. 3D printing on the other hand. Is such an comparatively underdeveloped and under-utilised technique that just sneezing next to a 3D printer is a form of news worth innovation.

wolfretcrap 6y ago

Raw material for 3d printing is ultra cheap specially when you try making your own filament from plastic pellets which sell for dirt cheap: https://medium.com/endless-filament/make-your-filament-at-home-for-cheap-6c908bb09922 https://medium.com/endless-filament/make-your-filament-at-ho...

mrlala 6y ago

Um why would there need to be 'media coverage' around technologies that everyone knows about and has basically been around forever? Media coverage dominates new technology [3d printing]... SHOCKER I TELL YOU!

meragrin_ 6y ago

> Edit: Goddamn it HN, why are you all responding to the pros/cons of 3D printing? Your complaint about media coverage was a whole sentence. Sentence and a half being generous. The complaint itself looks like a related comment at the end rather than the main point. Most of your post was pros/cons which was not clearly linked to media coverage. It really does look like a post about injection molding vs 3d printing.

ehnto 6y ago

I wonder if you had put your paragraphs in the other order, you might have had better luck. I was absolutely about to reply with some discussion on 3D printing, until I noticed the edit keyword and so read that first. I know it should be on the reader to fully read a comment, but it's the internet, so I adjust my comments sometimes to make sure my point is across before people jump ship.

Wowfunhappy 6y ago

> Edit: Goddamn it HN, why are you all responding to the pros/cons of 3D printing? My complain is about media coverage Because the appropriateness of rosy media coverage is dependent on the actual potential of 3D printing.

detaro 6y ago

For media coverage, does injection molding have flashy new use cases etc? My (non-expert) impression is that injection molding is the "boring default" for many use cases, and thus improvement in it won't see much coverage. (+ the specific submission is on a website specializing on 3D printing as a topic). If you show me an industrially made part and say "they injection molded that", the reaction is "sure, as you would", not "Oh? that's interesting, why did they do that?". Similar to how news will rather report on unusual building materials rather than run stories to remind people that bricks are cool too. (and if a home buyer insists on using something fancy new over bricks or whatever default would be more appropriate, that's their fault) That's not to say that defaults actually are boring if you deal with them directly, I find people explaining details of things like injection molding fascinating, but "we improved X in a standard industry process" just isn't as easy to make briefly interesting to mass audience and thus gets reported less.

lylecheatham 6y ago
Apple actually gets a decent amount of coverage for their very impressive injection moldings. Most advancements in IM today are not in the ability to make complex parts, but more in the ability to make them pretty. Apple makes many parts with extremely tight tolerances with almost no visual defects, and within the industry it's understood that it's extremely hard to make your IM parts look like Apple's for that reason.
- detaro 6y ago
  Yes, even mainstream media covers that every now and then (e.g. "Apple just bought an entire company making X to make even better macbooks/iPhones/..."), but as the parent poster complained 3D printing is getting more attention. Whereas "within the industry" is exactly the thing I'm talking about: the threshold for getting into more mainstream media is not necessarily related to actual importance and different from what field-specific or even just enthusiast perception focuses on. E.g. the bits and pieces I know about injection molding mostly come from "maker-type" publications that, while of course also talking about 3D printing a lot, also cover entry-level discussions of what happens if you try taking something to larger-scale production - and "forget about your product looking like an Apple product" is high on that list ;)

dfischer 6y ago

This kinda misses the point of the core. 3D printing transfers power inward vs outward. When this happens innovation explodes as the average individual has much more ability to produce on their own. Localized manufacturing is a subtle huge boom similar to computation.

panabee 6y ago

thanks for the comment. what are some other manufacturing techniques you think warrant more attention and research?

salt-licker 6y ago

This is an excellent point. 3D printing will likely never replace injection molding for plastic parts above a volume of a few thousand. This is well known in the industry but largely unexamined by the media. High-strength 3D printing however, of composites / metal, has a much higher market ceiling. Can certainly be cost-competitive with CNC and probably also expendable mold casting in the short-term.

snarfy 6y ago

The real money is selling large format 3D printers. For what they are they sure cost a premium.

rajnathani 6y ago

All these boats getting 3D printed (also those mentioned in the article) are made from composites, primarily carbon fiber or fiberglass based composites. Injection molding for plastic parts is easy and fast, however the current process it takes to make carbon fiber composites is highly energy intensive (one needs huge ovens), time consuming, expensive, and some approaches can even be highly labor intensive. This is also the reason why only the more expensive cars in the market have carbon fiber bodies as opposed to all cars/vehicles in the market. An example of the process of carbon fiber construction today from Koenigsegg's cars: https://www.youtube.com/watch?v=504I_hJDFck https://www.youtube.com/watch?v=504I_hJDFck