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Can the Lix 3D Printing Pen Actually Work?
szczys (3402149) writes "Brian Benchoff used science and math to prove that the performance shown in the Lix Kickstarter video is questionable at best. Check his evidence and see if he's done an appropriate job of debunking the functionality presented."
From the Hackaday post: "While we know the video is an outright misrepresentation of what any USB 3 powered device can do, We can’t figure out if the Lix is a viable product. We’re turning to you. Can you figure out if the Lix pen actually works? All we know is the Lix pen has a 4.5 Watt power supply from a USB 3 port. It’s possible for a USB 3 powered 3D printing pen to work, albeit slowly, but the engineering is difficult and we don’t know if the Lix team has the chops."
If they hadn't cut small parts out of their video every time the pen was shown in action.
Anyone else sick and tired of the overblown hype, the ridiculous promises and the fanboi delusions? It's molten plastic. I have a hot glue gun already, thanks.
I am baffled at what problem this is solving, what need it addresses and who would buy it?
See here, this has been done before. I see your theoretical Thermodynamic analysis and raise you something that actually works.
Of course it can work, just not continuously at that feed rate.
Ever had a cheap hot glue gun where you had to wait north of a minute after not even half a stick so the internal thermal mass can heat back up to working temp? Same idea.
Hackaday's maths are wrong, they build it on the assumption that a length of filament clearly shorter than two fingers width is 13cm long. Hackaday's news quality has been going down lately, I wonder why Slashdot is quoting them more and more.
Ok, I don't know if USB3 has enough wattage to do that. I've no idea what kind of plastic they're using, and that's going to be the most important factor here. As far as we know the things they created will melt if left in the window on a warm day. If that were the case, I'm fairly sure USB3 would have enough wattage.
When I was much younger I worked for a time running injection molding machines. As with most things in a factory the machines were getting old and had issues. One of them was that they'd leak after they were put into standby. 2 very heavy steel molds would come together and a nozzle would come forward and put 30 tons of pressure behind hot plastic. When it was break time I'd put the machine in standby which would keep the plastic and nozzle hot but relieve the pressure. Well, not all the pressure was gone so the nozzle would leak rather slowly. I quickly learned that if I took a piece of cardboard I could manipulate the flow of plastic out of the nozzle and make neat shapes. They looked almost exactly what they made in those videos. I find that a bit too much of a coincidences, so I'd have to say there's at least some credibility to what they're doing.
That being said, notice you can never see their other hand? I believe they are having to manually feed the plastic. Also, I don't think they are building vertically as it appears. The plastic probably wouldn't cool fast enough to allow that. I believe they are laying the plastic out on the paper, letting it could, then moving its position and tacking it there with a spot of new plastic. This was what I'd do. I made screwy flow pots, vases, coasters, etc... Finally, I want to point on that the ability to make stuff pretty much ends with what you see in the video. There wasn't much else you could do with it. Making anything that was robust enough for actual use would be nearly impossible.
So you need a computer, or at least a power supply with a USB port, to power a heater and motor? I have some doubts about the thing being cool enough to hold, too. Your fingers are about 3mm from a 180C heat source.
3D Doodler already has one of these things. Theirs seems to work, although they speed up the video too. For both, the results look like Silly String.
As one of the comments points out, where they claim the video shows 13cm extruded in about 5 seconds the actual amount extruded is nearer to 3cm. Using the same assumptions that the article makes 3cm in 5 seconds is well within the power available from the USB port.
* It preheats some element or reservoir for a limited time duty cycle
* It just draws more power from USB ; powerbanks happily support 2A and the '900mA specced USB port' on their macbook might also capable of delivering much more.
* The pen includes a rechargable battery capable of delivering more peak current. The pen could easily hold a 1Ah 3.7V lithion cell.
* They provide an adapter to plug it in 2 USB ports
* *
A glitch a day keeps the bugs away.
That's absolutely real, there is already a product like it, but bulkier.
Even if it works this is not 3D printing, at best its a craft tool - 'printing' requires reproducibility. Move along...
This isn't so much a hand-held 3D printer as it is a hand-cramp generator.
http://www.rootstrikers.org/
To get the heat need they could mix the plactic
with chemicals which develops heat.
What we really need to do is cure cancer. We need to solve the cancer problem, because that very problem is what is affecting our world at a global level too. When we learn to cure that disease symptomatically identified as bloating of cancer cells, we will learn to stop the cycle of economic bloat, corruption and oligarchy.
Which "cancer problem"? There are over what, 200 different diseases all under the umbrella of "cancer," each requiring a different cure or preventative measure. Yeah, we need to figure out how some of the base line errors occur in cell replication et all, which will help prevent quite a few types of cancer, but there's never going to be a magic bullet -- a "cure" for "cancer."
You sound like someone who doesn't want to solve the problem.
The dangers of knowledge trigger emotional distress in human beings.
"The math is also generous, as it doesn’t consider the phase change of the filament which would require even more energy. I didn’t include this because I can’t find a reference for the heat of fusion for ABS."
A cursory read of this analysis reveals the author didn't even understand ABS is an amorphous polymer and has no heat of fusion. The second sentence of the Wikipedia ABS article mentions this. With a lapse in understanding this large, one has to wonder if the author is competent in basic thermodynamics.
i think AC declaration is about as reliable a resource as hackaday 'thermodynamics'
What we need to do is cure the world from capitalism, in particular the delusion that economic growth will be sustained forever. This mistaken belief can, and will, kill many more people than cancer. Think war.
Anyone who uses the word 'chops' in that sense, invalidates their position.
Requiem for the American Dream
If you'd have RTFA you'd see that they already referenced that 3Doodler and use it as a point of comparison.
The "cancer problem" is that everyone dies. When you stop them dying of scarlet fever (aka strep throat) they die (50 years later) of cancer.
Watch this Heartland Institute video
it can't melt the plastic fast enough.
It wouldn't have to have a motor to drive the filament. It may work like a mechanical pencil where pushing a button/lever under your finger will feed the filament into the hot-end. It would certainly be simpler and smaller that way.
electric power at all by using something like one of those propane powered cordless soldering irons. A small flame could melt the plastic and a mechanism like that used in a mechanical pencil could use finger power to push the plastic into the hot-end.
I commented on a different site that their video was crappy. It was 1.5 minutes of self promoting douche bags showing nothing. Then a bunch of useless examples of the pen starting something and then poof done, just like a crappy 80s cooking show. Then in the end I saw no purpose for the stupid pen. Basically beyond some crappy 60's style art about the most useful thing they did was oddly repair a horribly torn shirt.
So to find out that these douchebags are not probably able to deliver surprises me not. I am also willing to bet that some MBA (who thinks he is smart) has a whole business plan where they will sell the consumable used by this pen for an absolute fortune.
All I can say is that my prediction is that with all the scummyness that I have seen so far that we actually haven't seen the worst yet.
The analysis hinges on the action shown in the video being in real time, when the kickstarter page clearly states that the video has been sped up.
The 3Doodler exists, and people were making devices like that from spare 3D printer extruders for many years before that, so there's no doubt that you can melt and extrude ABS.
The only question with the Lix is whether they can convert power into melted ABS efficiently enough to do so from a USB port. Technically USB 3 can provide 100 watts of power, which is far more than is needed to melt and extrude plastic. So if USB 3, with its power budget, is their target, it's doable.
Where it's iffy is the "any USB port", which means going back to 500 mA @ 5 volt USB 1 ports, which is only 2.5 amps. If they are extremely efficient at heating the ABS (most 3D printers' extruders radiate significant heat, since power efficiency isn't the priority) it might be possible to do it. Though it might be pretty slow. The 3Doodler requires some patience, so if the Lix is a lot slower, I think they'd get a lot of complaints. Though "it's slow on very old USB ports, faster on newer USB ports" isn't a bad story.
To the people saying that you can't extrude plastic vertically - you can. I've posted pictures at http://kickrev.blogspot.com/20... . It takes some practice, and a steady hand, but it's very doable.
Enable 3D printed prosthetics!
You sound like someone who doesn't want to understand the problem.
Kickstarter has hardly had any scams. Pretty much everything I've backed has been delivered, sometimes much later than planned but delivered eventually.
If you can't tell what is probably a scam and what is not, that's a problem that will haunt you in many other ways beyond just Kickstarter...
"There is more worth loving than we have strength to love." - Brian Jay Stanley
What we need to do is cure the world from capitalism, in particular the delusion that economic growth will be sustained forever. This mistaken belief can, and will, kill many more people than cancer. Think war.
Economic growth would have been sustained if we had kept our citizens from sterilizing themselves. Too late now though.. damage is done.
-1 Uncomfortable Truth
Nothing new here and the "drawing in air in 3D" has been implemented before this.
If you're playing the "we, as a civilization, should only be focusing on our worst problems" - why pick cancer? People are dying much earlier of completely treatable diseases, or just lack of clean water and proper sanitation. I would say that on a global scale, these are worse problem than cancer, and our resources would stretch a lot longer trying to fix these problems, as they *per person helped* are relatively simple problems.
So, what are you doing to fix this problem? Other than whining on ./?
No sweat. With antibiotic resistance building, folks will start dying of scarlet fever again before they have time to develop substantial cancers. No more cancer problem.
there's never going to be a magic bullet -- a "cure" for "cancer."
And if there was, it would probably destroy the economy and educational systems around the planet.
The Team doesn't look like they are trustworthy individuals at all. They feel like what I would imagine the Russian mafia or israeli intelligence or something like that to be. Creepy, really.
Yeah 'cuz resources are infinite, right?
I don't believe that those who are dying of clean water or sanitation are considered to be 'persons' under U.S. foreign policy so really the focus here is cancer of those considered to be persons.
Well, the world is bigger than the US. Don't assume that all /. readers are from there (I, for one, is not). I hope I'm still considered as a person, even if my home country has oil & gas reserves...
As soon as you admitted to not being a person I stopped acknowledging your reply.
USB 3.0 and 3.1 can supply 5V@2A or 12V@3A or 20V@ 5 Amps.
I think with 100W available melting a little plastic should be no problem.
I double checked their Kickstarter, and they say that it comes with a USB cable and a USB power supply, that it works with USB 3 and they're looking into a USB 2 solution. So they're not saying that the LIX will work on any USB port, they're saying that it'll work on their USB power supply, and with USB 3 (which has a much higher power budget, optionally). Given that running an extruder off of a battery is a dumb idea (it likely draws as much or more power than your laptop), running on wall power makes sense. Do you really need to do freehand ABS extrusion on an airplane?
Give that, it's pretty much the same functionality as the (awesome) 3Doodler, but in a sleeker package. It uses straight filament, has a motor and an extruder. The main difference is that it runs on 1.75mm filament instead of 3mm filament. 1.75mm filament shouldn't change the power consumption - basically you need to transfer the same heat into the plastic to melt the same volume of plastic to extrude, whether it's coming in a 1.75mm or a 3mm diameter filament.
Caveat: if the LIX extrudes a thinner line of plastic, then either it'll draw faster, or use less power. The LIX says it has an 0.6mm nozzle. I'm not sure what the 3Doodler's nozzle size is - about the same size, I think. And 3Doodler just announced a range of accessories, including smaller and larger nozzles. So it'll be interesting to compare them.
I will say that, after a fair amount of testing, running the 3Doodler on curved filament from a spool didn't work out too well - it tends to jam in the straight path through the pen. That's not so much of an issue with ABS, but PLA is pretty stiff, at least the 3mm filament that 3Doodler uses, so I'd recommend using the straight filament that the vendors sell, not filament from a spool.
Enable 3D printed prosthetics!
It has buttons labeled "speed controls" so I'm pretty sure that the filament is motor driven. Manually driven filament would be way to uneven.
They also only say that it works on USB 3 or wall power, and they include a USB wall plug for anyone with USB 2.
Not sure how they got a motor small enough to fit into a pen and feed filament...
Enable 3D printed prosthetics!
Yeah 'cuz resources are infinite, right?
From a practical perspective, yes, they really are. We use property laws, artificial scarcity and built-in obsolescence to create the fiction that they aren't so a few people who were born to power can maintain control over the rest of us. But it's all bullshit.
-1 Uncomfortable Truth
And this whole time I thought it was entropy, accelerated with an almost complete lack of forethought on recycling the finite amount of raw materials that exist in the first place that was the problem....
And this whole time I thought it was entropy, accelerated with an almost complete lack of forethought on recycling the finite amount of raw materials that exist in the first place that was the problem....
You thought wrong. The earth is vast and we huddle in our cities occupying a tiny portion of it.
-1 Uncomfortable Truth
It isn't about space, you idiot. Never was, never will be.