Care to help me select a 3D Printer?

Discussion in 'General Electronics Chat' started by strantor, Nov 29, 2013.

  1. strantor

    Thread Starter AAC Fanatic!

    Oct 3, 2010
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    I'm looking to purchase a 3D printer with my tax return, around Jan-Feb. My goals are as follows:
    expected budget is $500-$1,000, hopefully closer to the $500 mark.
    I'd like to be able to print something 16" long, 8" tall.

    I'm not seeing anything that satisfies both of those, so the second one is least important.

    I've never even seen a 3D printer, so I don't know what I'm looking at when I look at what's on the market. Seems like, since the majority of the affordable kits are open source, I am seeing a lot of radically different variants of something, all going by the same name. So if you're going to provide a recommendation, please provide a link; otherwise we might be talking about two totally different things.

    Right now, this is the one I've got my eye on. What do you think? Good? no? Is this type of printer capable of printing overhead? What I mean is, for example, if I wanted to print a hollow sphere or a pipe, can it do that? what would support the inside while you print "up-and-over?"
     
  2. strantor

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    Here's a 12"X16"X10" for $800.
     
  3. sirch2

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    Jan 21, 2013
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    I've been thinking about getting a 3D printer for the last year or more and keep putting it off due to cost vs. performance.

    Recently I have been considering getting a CNC Router/Engraver instead and then fitting it with an extruder - that way I would have both a CNC Router an a 3D printer. It would have less Z axis range than a 3D printer but could engrave and drill PCBs, panels, etc.
     
  4. HTPham

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    Dec 7, 2012
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    Wow, if the print area really is that big then $800 is awesome. Bought my Printrbot LC V1 (6"x6"x6") for $800, which is obsolete now since http://printrbot.com/shop/assembled-printrbot-plus/ (9"x8"x8") replaced it.

    Printers mostly have a 45-50 degree print limit until they start printing in midair, which doesn't work unless it's bridging a gap.

    Printing Torture test(you can see what I mean if you look at the top of the circles): http://solidoodletips.wordpress.com/2012/12/04/slicer-torture-test/torture_1/

    Bridging: http://www.3dgeni.us/a-bridge-too-far/

    Pipes will look like pipes but you might have to polish a bit, unless you print that pipe vertical.

    You can of course turn on "print supports" which prints a fragile snap off support for overhangs http://3.bp.blogspot.com/-YiWpHkTY7...twMVwQd-Jr8/s600/smart-doll-3d-printing-1.png
     
    Last edited: Nov 29, 2013
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  5. praondevou

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    I have no idea when it comes to to 3D printing.

    How about this one: http://www.peachyprinter.com/

    The project was funded through kickstarter I think. I don't know if it's already available.
     
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  6. GopherT

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    Do you have any interest in building your own from Internet plans (RepRap) or are you looking for a turn-key system? For $800 you can build something very nice and have the full support of a growing community and opportunity to upgrade part-by-part as you see fit.

    The turn-key system is had to modify and resolution is fairly poor. A heated build chamber is almost required for parts with any strength (so layers fuse together better).

    We have had a lot of fun with our RepRap Buying linear bearings and hardened guide rods made all the difference (vs plastic bushings). Our Resolution beats some $10k printers. We have sent parts to university of Texas El Paso for their benchmarking study so the $10k figure did not come from me.


    You can get started for $300-400 and make improvements from there. We have about $700 into ours. 9" x 9" x 9" build chamber. We found a sound-proof box used for old tractor-feed printers to keep offices quiet. It works great as a thermally insulated space for a heated build chamber.



    http://reprap.org/wiki/RepRap
     
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  7. strantor

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    Thanks, but that doesn't look like it will be able to deliver the resolution that I need, and I'm not sure about the material. It would be good for the kids to make little bracelet charms and toys, but as for what I need, I don't think it's up to the job.
    I'm not opposed to building it; actually I would prefer to assemble it so I understand it's inner-workings beyond being just a magic black box. But I don't really want to spend hours and days/weeks tracking down all the parts, or having them printed, and paying separate shipping for each little part. I have been looking at kits, since they seem to be perfect middle ground; a little bit cheaper than turn-key, but not exhaustive in searching for parts.
     
  8. strantor

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    So, it looks like the RigidBot 12"X16"X10" is going to be a wash, for now at least. Some independent research indicates that the RigidBot is a crowd-funded project that, while receiving 30X more money than they requested, has yet to release anything. Release date keeps getting pushed back and people are getting frustrated and pulling out. I doubt I could get it by tax season.

    So, this sends me back to RepRap designs, of which all seem to be limited to 200mmX200mmX100mm. I don't want to pay that much, or at all, for something that won't let me do what I want.

    So I'm wondering why all the reprap designs I've seen are limited to this small envelope. Is it a limitation of the software or firmware or hardware or what? Is there anything that would prevent me just buying the reprap electronics and fitting them to my own mechanical design which is much larger (say, 16"X48"X16")?

    Also, if I'm going to be building my own structure, I'd like to be able to use it for other stuff in the future, like CNC routing (possibly CNC milling if robust enough), CNC laser cutting, CNC plasma cutting, PCB engraving, novelty engraving, etc. - a truly multi-purpose CNC platform. For this reason, I'd like to fundamentally change the setup; instead of having the X axis controlled by moving the table back and forth, I'd like to have all 3 axes controlled from the top - a gantry on a gantry, and the whole top moves up and down for a Z axis.

    Will the reprap electronics and software let me get away with these design changes? Will the same software allow me to perform all the other functions that I want other than 3D printing? If not, is there other software that will work with the reprap electronics to perform all the other functions that I want?
     
  9. GopherT

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    The reprap software is flexible and I think there are subsections on the reprap link that I posted.

    Bigger build volumes are very possible with the software.

    Bigger build volumes raise an issue because the print bed needs to be heated and will require higher wattage power supply. Not a huge issue as 1200 watt power supplies are now available. You generally need 1 to 1.5 watts per square inch to maintain 120 C bed.

    Starting out with a smaller frame is not bad because the steel is the cheapest part. It just takes time to rebuild. The stepper motors, arduino, Ramps Shield, SD Card / display Shield, the power supply and 'hot end' (extruder) are all reusable. The bearings for the x and y on the moving bed can be reused - you just need longer rails.

    As you get bigger and bigger, the weight increases and the max printing speed slows (otherwise errors start as you slip steps). You also need a very flat surface with no sag. To do that and grow much beyond 10 inch spans, you need some expensive rails. We use an extruder with 0.3 mm nozzle. That means the span cannot sag more than about half that.

    Surprisingly, one of the biggest issues with 3D printing is that the filament does not stick to the bed. Sag, low temp and incompatible bed material cause the lack of adhesion.

    By the way, reprap software development continues constantly with self-tuning PID and variable acceleration of the stepper motors to minimize slippage of steps. I haven't looked what us going on since i haven't installed any updates lately (my son has the printer on campus this year). I am thinking about building another one for home.
     
    Last edited: Nov 30, 2013
  10. GopherT

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  11. THE_RB

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    I know people love their 3D printers, but from my point of view a CNC router/engraver is a much more useful machine.

    The big benefit of a 3D printer is that it can make hollow shapes (voids inside). Pretty much everywhere else it is worse; less resolution, less surface finish, issues with temperatures, sag etc, and being forced to use a limited usefulness material.

    A CNC router/engraver can machine things out of lots of different materials with quite high precision, can make tiny gears and mechanisms, cut or engrave metals like brass and aluminium, wood, or plastics. Also can engrave PCBs and front panels for projects.

    Anyway it's just my opinion, but to me a 3D printer is a fun toy, but a well setup CNC router/engraver is a very useful and powerful tool. :)
     
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  12. GopherT

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    One other cool feature of 3D printing is that you can print parts with 50% or less fill ratio with honeycomb fill patterns to make extremely light weight parts with much higher stiffness per weight than machines or moulded parts.

    I completely agree with RB that a CNC is more useful because of all the reasons he said. It is just nice to have DiY precision fabrication capabilities at home. Maybe the next tool will be a CNC instead of a second 3D machine.
     
  13. strantor

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    does this look legit to you guys? I know its open source so anybody is allowed to sell them, but I'm wondering about quality. I will probably go look at his stuff later this week.
     
  14. GopherT

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    It looks like he has done a really nice job of tracking down all the parts for you. The guy seems to have a solid investment in launching a new business - a website like that is not cheap or easy to build. It looks like he is in it for the long haul and, therefore, wants you to be happy, successful and recommend him to others. If he lets you stop by his shop, even better and less risk.
     
  15. Metalmann

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    Dec 8, 2012
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    I think I would have used at least 3/4" MDF and 1/2" drill rod.

    How big is this machine, capabilities?
     
  16. GopherT

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    8 x 8 x 8"

    It really depends on the acceleration of the print head along the x-y plane. Not much time is lost indexing up the z-plane slowly. Less rigid materials just require slower print times. 3/8" (or 10mm rods are the standard for this size printer and they work well. I have not used the MDF frame design. My son had the same criticism though. He is a metal Man (I guess metalman's is too).
     
  17. strantor

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    Yeah the MDF frame is what's got me leery. Everything I see online is laser cut wood or aluminum. I haven't seen the MDF frame or read anywhere that it's a good solution.
     
  18. strantor

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    also I haven't run across "PrintrBoard Rev E " in any of my reprap reading.
     
  19. GopherT

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    Printerboard is the latest and greatest - revision e is the latest. This guy is up to date.
    http://reprap.org/wiki/Printrboard
     
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  20. strantor

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    I'm driving 90miles (x2) this evening to go look at his wares. If I am confident in the MDF frame, I'm coming home with one tonight.
     
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