This is an interesting wrinkle to making 3D printers.
The process is related to the earliest methods where layers of plastic or metal powders are each sintered using a laser or focused light source.
Or layers of liquid resin is hardened using a laser.
As opposed to the newer methods which directly add elements by melting plastic.
The mechanical costs can be quite low in cost and primarily in the X-Y scanning mirror deflectors.
The low cost results from nearly no moving parts except for the scanner.
I presume the plastic resin is is hardened in the presence of the salt water and the laser.
Does anyone know about the chemistry he is using?
They're using a special resin formulated for this printer, but made to be cheap compared to others(Resin for the Form1 cost $145/L, for the Peachy, it costs $60). It's not that they needed a special formula, but most commercial resins are used as a glue, and sold in large vats.
The manufacturer is http://makerjuice.com/
And the Resin datasheet http://makerjuice.com/docs/SubG-TDS.pdf
The main reason this printer is so chap is that they've almost completely eliminated electronics.
The mirrors are moved by coils, that's hooked up to the Analog output of your computer's soundcard.
The liquid level(saltwater) that is added for new layers is a drip-feed with a switch to sense the drops, connected to the analog input of the soundcard...
From the video it says a layer of resin floats on the water which he adds drip by drip. He says it takes a whole lot of drips to raise the resin 1". It must print very slow.
The best variation of this that I've seen uses a Texas Instruments DLP digital cinema chip and a very bright light source to expose and activate the resin. It's much faster as the exposure is for the entire field at a time. When I read about it a few years ago I understood the developer was in the process of patenting it. I'm not sure where it went after that. This printer would not be $100 though; more like $10K-30K, but it would be much much faster than than any of the XY methods.
Let's remember that one of the first 3D print processes used paper, laser cut one sheet at a time, then bonded together. That's still a viable method for some designs.
Ingenious, if it works as advertised. I particularly like the salt water reservoir under the resin, dripping in to raise the resin level and minimize resin volume & cost.
Use of the computer's soundcard & mike input is cheap & novel. Better? Time will tell.
Best of all is the guy's video presentation of his progression from hacksawed mirrors and gnawed wood through the current still obviously handmade model.
Hope the guy makes it. He lists his brother and investor ny name.
I read recently that the patents on the laser-hardened-polymer 3D print method have either expired or are about to expire. I think we'll be seeing a lot more of this kind of development in the months to come.
What I don't get about the "$100" unit is the laser they're using. It looks like the kind of low-power device you'd use to tease a cat. 'Not sure how that can be used to harden a polymer, unless the polymer is very sensitive to light and the work needs to be done in a darkroom or light-tight housing.
According to the comments the current laser is 20mW.
Seems the resin is most sensitive to light at shorter than 400nm. It also needs to be stored in opaque containers, and has a max shelf life of 6 months.
Not to mention non-linearities and stiction in the galvanometers. All that aside, however, the sample that he did looks pretty good.
Does anyone know how durable this material is? The laser lithography models I've seen are rather brittle compared to those made of extruded ABS.
-Phil
Agreed on both counts, nice resolution and probably brittle from my experience with SLA parts. May require finish work, molding and casting to get a strong clean part.
He's siphoning the salt water out of the top tank through the drop measurer, saving the cost of a pump. All things considered, it's an ingenious system, but perhaps a PITA to set up and use periodically. If particularly sensitive to sound card and other PC settings, it may be preferable to dedicate a PC to it, which adds hidden costs.
He pitches portability as a feature, which is somewhat odd. I haven't seen people clamoring for that, and like a dedicated PC, I suspect that once you set this up and adjust the nuances into a good working configuration, best results will be obtained by NOT moving it and mucking about with all the variables. I wonder if you must drain the resin and corrosive salt water after each use? There are often significant convenience tradeoffs in any cost-reduced item.
Ok;
I think I understand why salt water is used.
The MakerJuice is slightly denser than water so salt is added to make the salt water denser than the goop.
Based on the video stream and the project description at Kickstarter, does somebody noticed if the laser building block stays at a fixed level atop the building tank, or it also floats up, as salted water drops are added to it?
You bring up an interesting question. There's only one laser beam -- not two intersecting ones. If the liquid polymer is clear, at what Z-level does the link-bonding occur? An what prevents that from happening at other Z-levels in the liquid polymer?
Don't ruin it for me, PhiPi. IMO you're the repository of all useful knowledge.
PFFFT! No offense to any chemists, but I elected to test out of Chem 102 in college because I hated Chem 101 so much; and it got me out of doing the labwork. It was those dang little ceramic crucibles that kept tipping over and dumping their payload all over the fussy analytical balance pans. Well, that, and having to wash labware. Yuck!
Does anyone ever get the feeling that these Kickstarters could be fraudulent?
Of course they COULD be fraudulent, its up to us to determine if we feel they are worth RISK.
Recall a short while ago, sub $50,000 3D printers were obviously impossible. Recall the $500 printrbot was declared impossible. It took a while to ship, and its not the best on the planet, but it works as advertised. Recall a filament extruder was impossible, until the Lyman Filament Extruder.
They got six times funding in three days. Obviously they don't need another $100, we can just wait and see if they deliver or not. Before we call fraud, bear in mind that sometimes these geezers can be clever.
You bring up an interesting question. There's only one laser beam -- not two intersecting ones. If the liquid polymer is clear, at what Z-level does the link-bonding occur? An what prevents that from happening at other Z-levels in the liquid polymer?
-Phil
Phil
Refraction is my bet!
As the UV rich laser light reaches the interface, its been decomposed or dispersed and does not significantly increases bonding.
I'm not totaly sure of the dispersed salt effects in the optics behaviour of the compounded system, nor any possible ionic bonding between resin molecules, salt and H2O that support or negates my thoughts.
If I totaly failed, my Optics Physics professors will start rolling in their graves, trying to freed themselves from their otherwise peaceful eternal rest, just to pull my feet at dawn, when I finally became tired enough to attempt some sleep.
I'd just realized that there is an extra item to take into account.
Perhaps the link-unbounded polymer also has very different optical properties from the link-bounded one.
This can enhace dispersion a lot at the interface level and decrease the link-bounding rate.
Also the presence of water (and perhaps salt) acts as a chilling, limiting the radius of influence of each laser bonding spot.
Not exactly the same, but similar to the way many eletrically applied coloidal paints do behave, by self limiting coating thickness according applied voltage differential and paint composition.
It would be interesting if someone could make some tests and check things like temperature raise and perhaps gas bubbles buildup, as a function of exposure time.
There are things like this that make me miss the 'old good times' where I could just 'skip' some lectures, to take a deep dive at the lab and just 'burn' something, whose smell resembled some weird and freaky dinner!:nerd:
The speed may not be a concern for too many as it's now at $246K, and trending towards $1900K
What does this refer to? The Veloso is said will be priced at $4K. It has a small (looks like ~100mm(2)) stage, but incrementally larger stages would be possible without going into the $100Ks. (The unit I was thinking of is much larger, and would be in the $upper 30Ks range easily. It uses digital cinema grade projector optics, whereas I think the Veloso uses consumer grade components.)
A big problem with DLP projectors is that the black pixels can never be all the way black. There's always some light leakage due to the way the mirrors vibrate. So the resin has to be sensitive enough for a reasonable exposure time, but not so sensitive that the "black" areas also become exposed.
A quick look on the Google Intranets shows a number of projects using DLP-exposed 3D printers. I gotta get out more often.
Here are some parts made by a DLP printer of a similar design:
His dollar figures referred to the Kickstarter commitment, not to the price of competitive units. The gist was that if that many people are interested, speed must not be a big deal.
Nothing much is an issue at $100. It could stink up a room and people would still pay that. So I'm not sure the Kickstarter commitment has bearing on what features would be desirable. It's nice to see the interest, though, as it will likely motivate people to explore more.
Mickster
Posts: 2,694
Comments
Maybe someone can show me how that is not possible.
The process is related to the earliest methods where layers of plastic or metal powders are each sintered using a laser or focused light source.
Or layers of liquid resin is hardened using a laser.
As opposed to the newer methods which directly add elements by melting plastic.
The mechanical costs can be quite low in cost and primarily in the X-Y scanning mirror deflectors.
The low cost results from nearly no moving parts except for the scanner.
I presume the plastic resin is is hardened in the presence of the salt water and the laser.
Does anyone know about the chemistry he is using?
Duane
The manufacturer is http://makerjuice.com/
And the Resin datasheet http://makerjuice.com/docs/SubG-TDS.pdf
The main reason this printer is so chap is that they've almost completely eliminated electronics.
The mirrors are moved by coils, that's hooked up to the Analog output of your computer's soundcard.
The liquid level(saltwater) that is added for new layers is a drip-feed with a switch to sense the drops, connected to the analog input of the soundcard...
Let's remember that one of the first 3D print processes used paper, laser cut one sheet at a time, then bonded together. That's still a viable method for some designs.
-- Gordon
Use of the computer's soundcard & mike input is cheap & novel. Better? Time will tell.
Best of all is the guy's video presentation of his progression from hacksawed mirrors and gnawed wood through the current still obviously handmade model.
Hope the guy makes it. He lists his brother and investor ny name.
What I don't get about the "$100" unit is the laser they're using. It looks like the kind of low-power device you'd use to tease a cat. 'Not sure how that can be used to harden a polymer, unless the polymer is very sensitive to light and the work needs to be done in a darkroom or light-tight housing.
-Phil
Seems the resin is most sensitive to light at shorter than 400nm. It also needs to be stored in opaque containers, and has a max shelf life of 6 months.
Or did I hear it wrong?
Mickster
Yeah, that struck me as odd at first, but then realized two channels, one X, one Y, so you would have 2^32 pixels.
Of course you have that whole precision vs. accuracy issue to deal with...
C.W.
Does anyone know how durable this material is? The laser lithography models I've seen are rather brittle compared to those made of extruded ABS.
-Phil
Agreed on both counts, nice resolution and probably brittle from my experience with SLA parts. May require finish work, molding and casting to get a strong clean part.
He's siphoning the salt water out of the top tank through the drop measurer, saving the cost of a pump. All things considered, it's an ingenious system, but perhaps a PITA to set up and use periodically. If particularly sensitive to sound card and other PC settings, it may be preferable to dedicate a PC to it, which adds hidden costs.
He pitches portability as a feature, which is somewhat odd. I haven't seen people clamoring for that, and like a dedicated PC, I suspect that once you set this up and adjust the nuances into a good working configuration, best results will be obtained by NOT moving it and mucking about with all the variables. I wonder if you must drain the resin and corrosive salt water after each use? There are often significant convenience tradeoffs in any cost-reduced item.
I think I understand why salt water is used.
The MakerJuice is slightly denser than water so salt is added to make the salt water denser than the goop.
Duane J
-Phil
-Phil
Don't ruin it for me, PhiPi. IMO you're the repository of all useful knowledge.
Yanomani
You bring up an interesting question. There's only one laser beam -- not two intersecting ones. If the liquid polymer is clear, at what Z-level does the link-bonding occur? An what prevents that from happening at other Z-levels in the liquid polymer?
-Phil
Physics was much cleaner and way more fun.
-Phil
Of course they COULD be fraudulent, its up to us to determine if we feel they are worth RISK.
Recall a short while ago, sub $50,000 3D printers were obviously impossible. Recall the $500 printrbot was declared impossible. It took a while to ship, and its not the best on the planet, but it works as advertised. Recall a filament extruder was impossible, until the Lyman Filament Extruder.
They got six times funding in three days. Obviously they don't need another $100, we can just wait and see if they deliver or not. Before we call fraud, bear in mind that sometimes these geezers can be clever.
Phil
Refraction is my bet!
As the UV rich laser light reaches the interface, its been decomposed or dispersed and does not significantly increases bonding.
I'm not totaly sure of the dispersed salt effects in the optics behaviour of the compounded system, nor any possible ionic bonding between resin molecules, salt and H2O that support or negates my thoughts.
If I totaly failed, my Optics Physics professors will start rolling in their graves, trying to freed themselves from their otherwise peaceful eternal rest, just to pull my feet at dawn, when I finally became tired enough to attempt some sleep.
Yanomani
I'd just realized that there is an extra item to take into account.
Perhaps the link-unbounded polymer also has very different optical properties from the link-bounded one.
This can enhace dispersion a lot at the interface level and decrease the link-bounding rate.
Also the presence of water (and perhaps salt) acts as a chilling, limiting the radius of influence of each laser bonding spot.
Not exactly the same, but similar to the way many eletrically applied coloidal paints do behave, by self limiting coating thickness according applied voltage differential and paint composition.
It would be interesting if someone could make some tests and check things like temperature raise and perhaps gas bubbles buildup, as a function of exposure time.
There are things like this that make me miss the 'old good times' where I could just 'skip' some lectures, to take a deep dive at the lab and just 'burn' something, whose smell resembled some weird and freaky dinner!:nerd:
Yanomani
What does this refer to? The Veloso is said will be priced at $4K. It has a small (looks like ~100mm(2)) stage, but incrementally larger stages would be possible without going into the $100Ks. (The unit I was thinking of is much larger, and would be in the $upper 30Ks range easily. It uses digital cinema grade projector optics, whereas I think the Veloso uses consumer grade components.)
A big problem with DLP projectors is that the black pixels can never be all the way black. There's always some light leakage due to the way the mirrors vibrate. So the resin has to be sensitive enough for a reasonable exposure time, but not so sensitive that the "black" areas also become exposed.
A quick look on the Google Intranets shows a number of projects using DLP-exposed 3D printers. I gotta get out more often.
Here are some parts made by a DLP printer of a similar design:
http://www.3ders.org/articles/20120405-miicraft-a-pico-projector-based-home-built-dlp-3d-printer.html
His dollar figures referred to the Kickstarter commitment, not to the price of competitive units. The gist was that if that many people are interested, speed must not be a big deal.
-Phil
Nothing much is an issue at $100. It could stink up a room and people would still pay that. So I'm not sure the Kickstarter commitment has bearing on what features would be desirable. It's nice to see the interest, though, as it will likely motivate people to explore more.
-- Gordon
* my mind is thinking fun thoughts ..*