Designing a 3D METAL printer - Page 2
Close
Login to Your Account
Page 2 of 4 FirstFirst 1234 LastLast
Results 21 to 40 of 74
  1. #21
    Join Date
    Jan 2007
    Location
    Flushing/Flint, Michigan
    Posts
    6,082
    Post Thanks / Like
    Likes (Given)
    238
    Likes (Received)
    4896

    Default

    Why does the field of 3-D printing feel so much like robotics and AI in the 80's ?

    "All we need is few break-throughs and these will certainly happen given the pace of technology".
    This despite the fact that those with unlimited cash have not been able to do it well.
    I do think it will work eventually, but I don't think I will be around to see it.

    Not to dissuade people from going into it.
    I can see it as a great way to suck money from investors in the short term. I know some guys who made a lots of money chasing artificial intelligence and robots in every house.
    If I believed in this I would not be going open source, always good to market "magic" to those with big wallets.
    Bob

  2. #22
    Join Date
    May 2005
    Location
    Austin, TX
    Posts
    4,404
    Post Thanks / Like
    Likes (Given)
    1259
    Likes (Received)
    1188

    Default

    Quote Originally Posted by CarbideBob View Post
    Why does the field of 3-D printing feel so much like robotics and AI in the 80's ?
    "All we need is few break-throughs and these will certainly happen given the pace of technology".
    Very good point Bob. I remember vividly when AI and especially Expert Systems were all the rage in the late 80's. Nowadays it's Cloud Computing and Social Media. Cloud Computing, known in the 2000's as Network Appliances, and known in the 90's as Client/Server

  3. Likes Oldwrench liked this post
  4. #23
    Join Date
    Jul 2006
    Country
    UNITED STATES
    State/Province
    Arizona
    Posts
    4,381
    Post Thanks / Like
    Likes (Given)
    17525
    Likes (Received)
    4086

    Default

    Quote Originally Posted by jdj View Post
    I always asked why they couldn't cast impellers and had to machine them from solid. Do you (or anyone) ACTUALLY mean to tell me that this new 3D METAL printing has surpassed a technology that has had MUCH MORE TIME to be finessed? Pardon my skepticism, but...
    Skepticism is normal. 30 years ago, wire EDM was slow as shit. Today, wire EDM it is very fast and cost effective for the right parts, but band saws are still the logical choice for cutting off a piece of stock. DMLS is the same thing. You are not going to economically print a simple shape whereas milling or turning would be far cheaper to produce the part--especially in high quantity. Low volume, extremely intricate and expensive parts (aerospace, medical, etc) lend themselves well to DMLS.

    Mechanical properties of castings are usually far inferior compared to barstock, and forgings are superior to barstock. Some materials are acceptable as cast, whereas titanium impellers are usually made from forgings when speaking of gas turbine engines to get the highest strength-to-weight ratio as possible. The impeller in your turbocharger is usually cast aluminum though.

    If DMLS parts have a higher strength compared to castings, that means the parts can be designed lighter and still have the same strength as the original casting. Aerospace is all about reducing weight down to the grams. Casting flaws are greatly reduced with DMLS as well. Also, the leadtime between changes goes to almost zero vs re-tooling a casting.

  5. #24
    Join Date
    Jun 2002
    Country
    CANADA
    State/Province
    British Columbia
    Posts
    2,069
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1355

    Default

    Hi All:
    This is a great thread; I've been looking with interest at this technology for some time, and have rehearsed many of the arguments in my mind that I'm hearing on the forum, so we're thinking in very similar ways.
    So I decided to test my assumptions directly and did two things.

    First I ordered a smallish, moderately complex part (basically a 2" diameter, "C" shaped piece with two little co-planar flanges on the ends) from one of the few prototype facilities who has an EOS machine, and had it sent to me just as it comes off the machine with no post processing whatsoever (they'll polish or shot peen or glass bead the parts for you if you request it).

    I originally issued RFQ's to two companies; one was Morris Technologies the other shall remain nameless for reasons that will become apparent later.
    Morris Technologies is now owned by GE and responded to my RFQ with demands for a mountain of information about my company and very solemn declarations to sign...Homeland Security at work I'm sure. (I'm up in Canada, so I represent a security risk and all that other pious waffle but I digress).
    The other company said "sure" so I went with them.

    The second thing I did was to contact EOS and ask for all of the information they could provide.
    I have a project that I thought would be perfect for this technology; it's in the veterinary medicine field, and the parts I'm currently machining from billet are more expensive to make than I'd like.
    With this as an incentive to take me seriously, I got a good initial response from the sales team, but no substantive answers to the many technical questions I have.
    I will have to pester some more, I think!

    So here are my findings:
    Gentlemen, don't sell your machine shops off to invest in one of these machines just yet, and here's why:
    1) The part was expensive; about 30% more than a part machined from plate
    2) It was dreadfully inaccurate in some quite specific ways.
    3) It was rougher than guts

    Features that were supposed to be flat and co-planar were not; and they were out by a lot (more than 5 degrees out of co-planarity on a part 2" long; parallel surfaces 0.315" diameter and 0.200" apart out by more than 0.010" etc etc)
    Features that were supposed to have sharp corners did not.
    The surface did not polish cleanly even with quite aggressive stock removal, and there was a visible step in the build where the build-in-progress was disturbed (a forklift driving by next door??)
    Where it did quite well was in producing all the fancy blended radii that were going to have to be hand- dressed onto the billet part, and when I first pulled the part from the box, it LOOKED like what I'd modeled in Solidworks, so I thought it was going to be great until I looked more closely.

    Overall it was not a success, and was unuseable for the application which demanded a decent level of precision and a nice surface finish; so it was a $450.00 experiment that failed and was not salvageable by any reasonable means (I made a billet part for the customer).
    But now I know!!

    So here's what I think in general:
    For a certain class of part it's a wonderful advance for which new applications will present themselves that we haven't even thought of yet.
    Smallish, complex but low tolerance geometry together with low volumes and high value are perfect parts for this.
    Tailored materials and anisotropic material properties are another domain where you can do cool new things.
    Additive and subtractive processing together (as was mentioned with the Matsuura) will let you do amazing things too.

    For run of the mill parts like the vast majority of mechanisms require however, it has zero hope of competing now and forever.
    Here's why I think that's true:
    1) It's a process that needs lots of time and a lavish energy budget to make even a single small part, and both go up as the cube of the build size.
    2) The fact that it's a thermal process means distortion and thermal stress in the part as the part is successively built, with a new hot layer being deposited onto a cold layer (which is why my C shaped part curled so badly).
    3) The physics of droplet cooling govern the resolution of all kinds of geometry like the sharpness of corners, and the verticality of vertical walls built up in successive layers.
    4) There is a basic lack of material versatility in two profound ways; first the difficulty of avoiding cross contamination as a particular powder is changed out to a new, different powder; second, the limited powders available for processing.
    5) It's severely anisotropic; in X and Y the material properties are quite good; in Z they're terrible, just as is true for every layered build process in any material.

    Now, as Robin Coope pointed out, he and I are conspiring as to how we can get our mitts onto one of these.
    So why in hell, having just knocked the process severely, am I intending to invest effort into this?
    The answer lies in the nature of the work we do together, for which this technology has a great deal of promise.
    I think it's going to be a super tool if you have the right kinds of parts to put on it.
    I think we have the right kinds of parts and Robin has an avenue into that market that most of us never even get a sniff at.
    By the way, don't ask; it's a secret, and if we tell you we'll have to kill you!!!
    Cheers

    Marcus
    Implant Mechanix – Design & Innovation - home
    Vancouver Wire EDM -- Wire EDM Machining

  6. Likes Toms Wheels, AndyF, lazlo, grg12, Oldwrench liked this post
  7. #25
    Join Date
    Feb 2007
    Location
    Boston MA
    Posts
    904
    Post Thanks / Like
    Likes (Given)
    216
    Likes (Received)
    671

    Default

    Quote Originally Posted by Pete F View Post
    Do you have any links? I'm curious to see it in action.

    Personally I'm far more confident in the future of 3D printing than some seem to be here, at least when it comes to plastics. I definitely believe that well within my lifetime each home will have a 3D printer and many things that would be manufactured in bulk and distributed will instead be printed at home as one-offs. Call me a dreamer, but even I was very close to building a 3D printer for casting patterns but decided I didn't have enough call for it.

    Metals? Yeah maybe a lot further away yet, but once affordable plastics are refined I don't think metals will be that far behind.

    Pete
    There are many existing fabrication processes like casting, machining, forging, blanking, injection molding, blow molding, building from plate, etc. All of those processes have their pro's and con's. Most all the people I've talked to that imagine a future where we push a button and a thing is 3D printed for us have little understanding of the tradeoffs of those processes (I don't mean you, I mean the layman). Those folks think all of the shortcomings of 3D printing will somehow be solved... the fact that it is slow, inaccurate, not strong, etc. But there is no basis for the belief that all of those processes will be solved.

    It's like when CNC machines first came out. I heard how they were the future and how some day, we would all have a CNC machine and you would just load something in and out would come a finished part. But that ignores time, cost, structural strength, etc. A cast part will never be as strong as a forged part just because of the nature of the process. It's not a technology limitation, but a limitation of the laws of physics. Same with 3D printing. A 3D printed part will never be as strong as an injection molded part of similar size and thickness. And there will never be the range of printable materials as there is for injection molding. And because 3D printing melts a material and deposits it in small quantity, whereas injection molding melts a material and deposits it all at once, molding will always be faster.

    So when people think that injection molding will be replaced with 3D printing, they also assume that the cost of consumer goods will stop being important in the future, and that the strength of materials will cease to be important, or the size of things will cease to be important. I say there is no way any of those things ever happen. Rather, cost, size and strength will become more and more important. I think we've all seen that in machining...our machines are more precise and faster than ever... and that doesn't make those machines more applicable to general use - it makes them much more specialized and expensive. It would be reasonable for a layman to have a metal lathe in his garage 50 years ago. It's totally unreasonable for a layman to have a Mazak Integrex in his garage today.

    As 3D printers become more capable, they will get more specialized and their uses will be more and more obscure. There will be complicated parts where 3D printing is used because the shortcomings of time and expense are worth it for the benefits of geometry complexity.

    It's a neat field to be in, but it's changing so fast that the investment in equipment must be massive.

  8. Likes Oldwrench liked this post
  9. #26
    Join Date
    Jul 2006
    Country
    UNITED STATES
    State/Province
    Arizona
    Posts
    4,381
    Post Thanks / Like
    Likes (Given)
    17525
    Likes (Received)
    4086

    Default

    Excerpts from July 2012 SAE article about DMLS:

    Aerospace leads in additive manufacturing

    “Compared to traditional methods where you have to build parts with multiple steps or need multiple parts brazed together, additive manufacturing allows you to combine these into one process” to reduce cost and time, Horine explained to AE.

    “Some of our biggest successes are making parts for customers where we combined multiple components into a single part,” agreed Tim Warden, VP of Sales and Marketing at Morris Technologies, a leader in the use of metal-based additive manufacturing.

    The company started developing such parts in 2003 and now boasts 21 additive manufacturing machines running 13 various materials. They employ both direct metal laser sintering (DMLS) from EOS as well as electron beam melting (EBM) from Arcam.

    One example of parts consolidation is a part once composed of 26 individual machined components that were braised or welded together to form a working unit. Using metals-based additive manufacturing, Morris created a single part in a single process. Using such a simple method for making complex parts also means lighter components optimized for strength in only critical areas.

    Low production rates are also a factor in its popularity in aerospace. “Remember, in aerospace, 50 to 100 parts a year is production, unlike automotive where production means 100,000's of parts,” said Warden.

    "Ninety percent of the parts that we make from our additive machines we do some type of secondary machining operations using our installed CNC equipment.”
    Castings commonly go through post machining operations on critical features, but are usually cheaper to produce than a 100% machined component.

    From the stuff I have read, Morris was about 10 years ahead of their nearest competitor. The intricate DMLS parts we had made looked absolutely atonishing (no post processing) compared to the parts we had made a few years earlier.

  10. #27
    Join Date
    Jul 2006
    Location
    Australia (Hobart)
    Posts
    3,022
    Post Thanks / Like
    Likes (Given)
    421
    Likes (Received)
    1933

    Default

    Quote Originally Posted by Pete F View Post
    Metals? Yeah maybe a lot further away yet, but once affordable plastics are refined I don't think metals will be that far behind.
    Pete
    ..... at a WAG of 3 orders of magnitude increase in energy expenditure. Which doesn't mean that I wouldn't try to get my hands on one, of course.

    PDW

  11. #28
    Join Date
    Jul 2008
    Location
    Sydney, Australia
    Posts
    3,753
    Post Thanks / Like
    Likes (Given)
    2054
    Likes (Received)
    1279

    Default

    Yes well I'm sorry to swim against the tide, but I'm afraid I can't agree with some of the arguments that are being put forward. The average consumer product is not especially high tech and intricate. Sure there are plenty of examples that are, but I'm literally looking around my desk now and I see a paper tray (full ... sadly), a coffee mug (empty ... even sadder), a pen holder thingie etc etc etc. All punched out by the squillion in some Chinese factory, where they go in to an elaborate supply chain before reaching me here. I also see computer monitors, a keyboard, and myriad other "high tech" pieces of equipment that will be continued to be manufactured in specialised facilities for as long as I can foresee. Go in to the kitchen and we have cupbords full of plastic containers etc. none especially high tech.

    As energy and therefore transport costs increase, I firmly believe we will see an era where transporting crap from one side of the world to the other, just because it's cheaper to punch it out on the other side of the world, will diminish, and it will be printed at or close to the final user.

    As I say, more than happy to swim against the tide here, but I've seen enough of the plastics to see where it's all going. It's the way it went with conventional 2D printing (ask an Australian book seller how they're doing!), and it will, in my humble opinion, be the way it will it will go with 3D printing, for SOME products.

    My 2 cents' worth of opinion.

    Pete

  12. #29
    Join Date
    Jul 2006
    Location
    Australia (Hobart)
    Posts
    3,022
    Post Thanks / Like
    Likes (Given)
    421
    Likes (Received)
    1933

    Default

    Quote Originally Posted by Pete F View Post
    As I say, more than happy to swim against the tide here, but I've seen enough of the plastics to see where it's all going. It's the way it went with conventional 2D printing (ask an Australian book seller how they're doing!), and it will, in my humble opinion, be the way it will it will go with 3D printing, for SOME products.

    My 2 cents' worth of opinion.

    Pete
    I'd like you to be correct but transport costs are going to have to rise a LOT first.

    Current example - it's cheaper to mine, transport by rail, cross-load, transport by ship, smelt, manufacture and *ship back* to country of origin red and black dirt than it is to turn that same stuff into steel locally. Leaving out actually making anything from that steel.

    I love the idea of 3D printing and I'm certain you're right for niche areas.

    PDW

  13. Likes hanermo, Oldwrench liked this post
  14. #30
    Join Date
    Feb 2007
    Location
    Boston MA
    Posts
    904
    Post Thanks / Like
    Likes (Given)
    216
    Likes (Received)
    671

    Default

    Quote Originally Posted by Pete F View Post
    Yes well I'm sorry to swim against the tide, but I'm afraid I can't agree with some of the arguments that are being put forward. The average consumer product is not especially high tech and intricate. Sure there are plenty of examples that are, but I'm literally looking around my desk now and I see a paper tray (full ... sadly), a coffee mug (empty ... even sadder), a pen holder thingie etc etc etc. All punched out by the squillion in some Chinese factory, where they go in to an elaborate supply chain before reaching me here. I also see computer monitors, a keyboard, and myriad other "high tech" pieces of equipment that will be continued to be manufactured in specialised facilities for as long as I can foresee. Go in to the kitchen and we have cupbords full of plastic containers etc. none especially high tech.

    As energy and therefore transport costs increase, I firmly believe we will see an era where transporting crap from one side of the world to the other, just because it's cheaper to punch it out on the other side of the world, will diminish, and it will be printed at or close to the final user.

    As I say, more than happy to swim against the tide here, but I've seen enough of the plastics to see where it's all going. It's the way it went with conventional 2D printing (ask an Australian book seller how they're doing!), and it will, in my humble opinion, be the way it will it will go with 3D printing, for SOME products.

    My 2 cents' worth of opinion.

    Pete

    3D printing does not save appreciably on transport costs, and any savings are more than eaten up by energy costs. The printer does not create the plastic - the plastic is loaded into the machine. That plastic still must be manufactured and transported to the consumer, which is not really any different than the cup being manufactured and transported to the consumer.

    One could argue that there is an additional step of transport of the materials from the manufacturer to the molder... but locating close to suppliers is already something that is done by manufacturers (like automotive manufacturers locating close to rail transport). There is also the fact that a 3D printer will always be more wasteful for two reasons. First, there will always be break downs and mistakes when something is done by an untrained person vs being done in a large manufacturing company on a production line with the bugs worked out. Second, it will always consume more energy. For injection molding, you are can realize huge volume efficiency benefits - it's a lot cheaper energy wise to have a warehouse in a cheap-rent-cheap-energy location cranking out 1,000,000 widgets per month than it will be to have 1,000,000 individual 3D printers located in 1,000,000 homes with 1,000,000 different energy costs all making one individual cup.

  15. Likes Oldwrench liked this post
  16. #31
    Join Date
    Dec 2007
    Location
    Netherlands
    Posts
    100
    Post Thanks / Like
    Likes (Given)
    9
    Likes (Received)
    21

    Default

    As said before, 3D printing will mostly be used for one-offs or special products. This is a really good example of what it can do. Good luck machining this with your CNC:

    Case Stories - (Im)possible crossing - Compolight

  17. Likes Pete F liked this post
  18. #32
    Join Date
    Apr 2013
    Location
    Canet, France
    Posts
    6
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    It is great to see such a lively discussion on this subject! I am always surprised by how few people know about 3D printing (let alone in metal), and the meh, complacency, with which it's met.

    @ lazlo
    The EOS and Matsuura machines are used for prototyping and one-offs. According to the American Machinist articles (I linked above), they've never been used in production, for obvious reasons.
    That is largely true, but what has changed is that the prototypes can be used in real world situations now because their strength is greater or equal to production parts. This opens up the possibility of 'mass producing' customized designs. Here is a good example of additive manufacture (aka 3D Metal Printing) being used in mass production: http://www.3ders.org/articles/201304...-printing.html

    @ jdj -
    I always asked why they couldn't cast impellers and had to machine them from solid. Do you (or anyone) ACTUALLY mean to tell me that this new 3D METAL printing has surpassed a technology that has had MUCH MORE TIME to be finessed? Pardon my skepticism, but...
    I think I have mentioned that EOS has reported an increase in strength as opposed to forged parts. This and the ability to print any geometry (internal structures etc) really sets the technology apart.

    As has been mentioned, 3D printing will never ever replace injection molded cups. The more complex the part however, the more sense it makes to print it. That is the defining point - it takes the same amount of time to make a simple metal part as it would to make a similar sized part with thousands of inclusions and chambers. The benefits of this tech will come in the for of more efficient parts.

    As Philabuster pointed out...

    DMLS is the same thing. You are not going to economically print a simple shape whereas milling or turning would be far cheaper to produce the part--especially in high quantity. Low volume, extremely intricate and expensive parts (aerospace, medical, etc) lend themselves well to DMLS.
    A very good example: Aerospace industry adopting 3D print technology « Ponoko – Blog

    To quote from the article:
    Reducing the weight of an airplane by just one kilogram can result in fuel savings of $3,000 per year
    The simplest way to speed up the 3D Printing production process is to parallel print, have many machines printing at the same time. However this is not practical when each sintering machine costs $1,000,000.

    The big Additive Manufacture companies are closed source, they have pumped tones of cash into a few engineers and have made super expensive machines in a hope to turn a profit. Big companies go for it because it is the only option. We are hoping that by open sourcing 3D Metal Printing we can make it more accessible.

    @ implmex, very interesting reading your experience with these companies... could I re-post it on my forum?

    @ Pete F
    The average consumer product is not especially high tech and intricate.
    This technology will translate into more efficient cars, airplanes etc, as has been mentioned, this is not something that will replace the injection molded cup for example - it has it's own rather powerful role to fill.


    @SRT Mike -
    it's a lot cheaper energy wise to have a warehouse in a cheap-rent-cheap-energy location cranking out 1,000,000 widgets per month than it will be to have 1,000,000 individual 3D printers located in 1,000,000 homes with 1,000,000 different energy costs all making one individual cup.
    And that just makes sense. Where 3D Metal Printing is doing well is for complex more efficient designs.

    If more people had access to 3D Metal Printers, this world would be a much more efficient and better designed place. That is our goal anyway!

  19. #33
    Join Date
    Jul 2006
    Location
    Australia (Hobart)
    Posts
    3,022
    Post Thanks / Like
    Likes (Given)
    421
    Likes (Received)
    1933

    Default

    Quote Originally Posted by metalbot View Post
    If more people had access to 3D Metal Printers, this world would be a much more efficient and better designed place. That is our goal anyway!
    If more people had access to 3D metal printers, the world would be awash in even more guns.

    Whether you consider this a good thing or a bad thing is a matter for the individual. I'm just saying, this is what will happen. Life with these printers would become more interesting anyway.

    PDW

  20. Likes Oldwrench liked this post
  21. #34
    Join Date
    Jul 2008
    Location
    Sydney, Australia
    Posts
    3,753
    Post Thanks / Like
    Likes (Given)
    2054
    Likes (Received)
    1279

    Default

    This technology will translate into more efficient cars, airplanes etc, as has been mentioned, this is not something that will replace the injection molded cup for example - it has it's own rather powerful role to fill.
    My opinion is different, but that's all it is, merely an opinion. I think it's not just about efficiency, it's about the ability for consumers to ultimately personalise the good they "buy". Many of the things in our home make no sense if one looks at it purely from a logical, efficiency perspective (though as I said above, I do believe this will be a factor). Right now I can hear our bread-maker running in our kitchen. Logically why on earth would anyone own a bread maker? In Australia we can wander in to the local supermarket and buy good bread for a buck. Literally. It costs many times that to make our own. So it will be with 3D printers, people will make household items, customised to precisely their own specifications using an easy to use GUI interface simply because they can.

    Anyway, I was working in the workshop this morning when this story was broadcast on the news. It reminded me of this thread Cookies must be enabled. | The Australian I was working with a colleague a few weeks ago who is also a full-time student in bio-medicine working in this field. It was fascinating talking with him and it's quite amazing what they can do now. It's not "almost here" it IS here, but because it involves human organs the process to get it approved, even for clinical trials, is long and convoluted.

    Pete

  22. #35
    Join Date
    Jul 2006
    Location
    Australia (Hobart)
    Posts
    3,022
    Post Thanks / Like
    Likes (Given)
    421
    Likes (Received)
    1933

    Default

    Quote Originally Posted by Pete F View Post
    My opinion is different, but that's all it is, merely an opinion. I think it's not just about efficiency, it's about the ability for consumers to ultimately personalise the good they "buy".
    I think I already said that in my post before yours :-)

    FWIW I agree with you. 1st World society has gone waaay beyond the concept of 'need' already. If these things can be made for less than, say $5K and are minimally useful, they'll sell like - iPads.

    PDW

  23. #36
    Join Date
    Apr 2013
    Location
    Canet, France
    Posts
    6
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    So coming back to the original challenge, designing a 3D Metal Printer, I have a few questions that I would like to just put out there... these questions are mainly to do with the metal and engineering work associated with project (I am unfamiliar with this field being an electronics guy mainly).

    Ok, regarding the 'powder system' (the powder system is all of the components that handle the powder) the biggest challenge facing us is in this aspect is precision. In order to make the printer affordable, we need to use smaller powder layers and finer powders. We have sourced pure titanium and TI-A6-V4 alloys down to 3 microns.

    The difficulty comes in spreading a fine (~30um) layer of this powder due to electrostatics, imperfections etc... Three things are needed for this to happen.

    1 - We need a very flat build surface. Basically, it needs to be a very flat metal plate. We want a consistent layer of 30um over an area at minimum 150mm^2 . How would one source a precise part like that? A tolerance of less than 5um over that whole surface area would be needed if we are going to keep the sintering consistent, we don't want one end of powder layer to be 60um thick and the other 20um. So what kind of cost would that incur?

    2 - That very flat build surface will be connected to a linear actuator, a ball screw driven by a stepper motor in order to get the build surface to move down a very precise amount... so for the build platform to move down 30 um you would have to calculate the number of steps the motor would have to turn.

    What is the best type of ball screw to use for a high precision application like this? Also what is the best way to mount the ball screw and motor to the build platform.

    3 - The powder needs to be spread in a squeegee type fashion. This is the simplest method for spreading powder layers. The distance the build platform drops sets the layer thickness, all the powder 'roller' does is push the powder over the dropped area. The excess powder will just fall into the recycling container. What we obviously don't want is breaks in the powder layers, which is hard to do with such fine layers due to electrostatic adhesion. So what shape would be best for the powder roller or spreader? A cylinder (as in the illustration below)? Perhaps a right angle with a sharp edge. I am wondering how much the shape of the powder spreader will affect the evenness of the layers.

    powder-system.jpg

    Other questions which I will save for a later date are to do with cladding the 3D Printer frame and making it gas tight... one idea was to purchase an industrial fridge and modify it as an enclosure .

    We are trying to document all this info into the wiki so that we don't go in circles and can actually get some forward momentum going...

    Best, Jethro.

  24. #37
    Join Date
    Feb 2004
    Location
    peekskill, NY
    Posts
    23,554
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    3715

    Default

    "...people will make household items, customised to precisely their own specifications using an easy to use
    GUI interface simply because they can."

    Ok this sparked my interest.

    The gedankenexperiment: a good 3D metal printer exists. It's in your house.

    What do you make?

    What would you *want* to make?

    Why does it have to be metal, and how is it better than what you can buy
    off the shelf now?

    How does it disrupt the existing supply chain and marketing for every other
    piece of houshold equipment that you use right now?

    Ground rules: nothing with wiring, nothing with compressed gasses.

  25. Likes digger doug, Oldwrench liked this post
  26. #38
    Join Date
    May 2005
    Location
    Austin, TX
    Posts
    4,404
    Post Thanks / Like
    Likes (Given)
    1259
    Likes (Received)
    1188

    Default

    Quote Originally Posted by metalbot View Post
    The EOS and Matsuura machines are used for prototyping and one-offs. According to the American Machinist articles (I linked above), they've never been used in production, for obvious reasons.
    That is largely true, but what has changed is that the prototypes can be used in real world situations now because their strength is greater or equal to production parts. This opens up the possibility of 'mass producing' customized designs.

    Here is a good example of additive manufacture (aka 3D Metal Printing) being used in mass production:

    3ders.org - GE to mass-produce critical jet engine part use 3D printing | News & 3D Printing News

    That's a copy of the American Machinist article about GE buying Morris Technologies (which uses EOS machines) last December. They haven't started making anything, let alone mass production.

    Like every other 3D Printing article for the last 30 years, "
    GE's aviation division, the world's largest supplier of jet engines, is to use 3D printing technology to produce a fuel nozzle for use in jet engines."

    Re-read Implex's outstanding post about the part he he made by Morris Technologies on an EOS machine. They've got decades of refinement to go...


    Quote Originally Posted by implmex View Post
    For a certain class of part: Smallish, complex but low tolerance geometry together with low volumes and high value are perfect parts for this.
    Additive and subtractive processing together (as was mentioned with the Matsuura) will let you do amazing things too.

    For run of the mill parts like the vast majority of mechanisms require however, it has zero hope of competing now and forever:

    1) It's a process that needs lots of time and a lavish energy budget to make even a single small part, and both go up as the cube of the build size.
    2) The fact that it's a thermal process means distortion and thermal stress in the part as the part is successively built, with a new hot layer being deposited onto a cold layer (which is why my C shaped part curled so badly).
    4) There is a basic lack of material versatility in two profound ways; first the difficulty of avoiding cross contamination as a particular powder is changed out to a new, different powder; second, the limited powders available for processing.
    5) It's severely anisotropic; in X and Y the material properties are quite good; in Z they're terrible, just as is true for every layered build process in any material.

  27. Likes Oldwrench liked this post
  28. #39
    Join Date
    May 2005
    Location
    Austin, TX
    Posts
    4,404
    Post Thanks / Like
    Likes (Given)
    1259
    Likes (Received)
    1188

    Default

    Quote Originally Posted by Pete F View Post
    It reminded me of this thread Cookies must be enabled. | The Australian I was working with a colleague a few weeks ago who is also a full-time student in bio-medicine working in this field. It was fascinating talking with him and it's quite amazing what they can do now. It's not "almost here" it IS here
    Pete, that's not what I'm getting from that article:

    "Australian scientists are researching the construction of human body parts by using 3D printing

    Researchers from Melbourne's St Vincent's Hospital ... believed it would be possible to manufacture living tissues like skin, cartilage, arteries and heart valves using cells and biomaterials within five years.
    By 2025, scientists could fabricate complete functional organs, tailored for an individual patient."

    So the researchers are saying they have nothing, yet. But that within 5 years they might be able to make small samples of skin tissue, and within 15 years make organs.

    I've run advanced technology projects long enough to know that when the researchers tell you a time-frame, if you double it, you're still on a very aggressive schedule
    Cool idea though!

  29. #40
    Join Date
    Jul 2008
    Location
    Sydney, Australia
    Posts
    3,753
    Post Thanks / Like
    Likes (Given)
    2054
    Likes (Received)
    1279

    Default

    Actually they've already made human organs from scratch, a liver I believe.

    Bioprinters already exist right now. My colleague was working on tissue cell scaffolding. The technique he was developing didn't use 3D printing, however there was a competing technique that does use 3D printing. 3D printing is already out there, just sometimes it's not in the form machinists may associate with. Don't ask me about any of the medical side of things, I don't know much about it at other than what I was told and have read. I did however help him develop a technique to accurately measure his little Frankensteinian creations. I insisted as a result he mentioned me when he accepted his Nobel prize. Apparently it was a deal. Woo Hoo!


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •