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New build : 5 controller + CAM options - Your opinions please!

Discussion in 'Controller Boards' started by Agamemnon, Apr 25, 2014.

  1. Agamemnon

    Agamemnon Well-Known
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    Hi folks,

    I, like you, have become hooked with the obsession that is DIY CNC! I've started planning my first build, and have come to understand that I should properly figure out my electronics (and software) first.

    I have come up with some options and would appreciate your advice. (Links at bottom of post if you're interested).

    GRBL vs. tgFX vs. Linux CNC
    As a first time user/builder, I have no experience with using or setting up the controller/CAM software for CNC.
    So, I'm not sure if I should start "small" (/simple?) with an Arduino + GRBL, or if I should start with a more capable processing system. As a result, I am also considering tgFX (on a TinyG setup), or Linux CNC (via a PC, and possibly later on a Beaglebone Black). Difficult decision!

    Either way, I plan to make an initial build that has a relatively small footprint and doesn't need fast movements. I plan to make this rigid enough (possibly fixed gantry) to machine aluminium blocks and plates, in order to build a larger, stronger and faster unit later. This means that I would like to select electronics and software that can be used when upgrading to a more powerful system.

    My basic electronics cost breakdown is as follows. (Without shipping costs, or power supplies - requirements still to be worked out)


    Option 1 : GRBL; $92 total
    Arduino Uno ($30) + gShield ($20) + 3x DRV8825 drivers (3x $14) = US$92 system with replaceable 2.2A/45V drivers, PC required.
    :: Pros : USB connection to PC; cheap, simple setup; drivers cheap and replaceable if blown.
    :: Cons: 3 axis only; weak processor (this matters, right?)
    [​IMG] [​IMG] [​IMG] UnoR3 + gShield + DRV8825

    Option 1b: [$105 Upgrade of Option 1: Driver upgrade] $197
    Option 1 ($92) + replace the Pololu-style drivers with offboard Massmind.org THB6064AH drivers (3x $35) = $197
    :: Pros : Good drivers for the price; Can be done later to minimise up-front costs.
    :: Cons : Requires some electronics knowledge to work it out; not sure if the arduino can handle the voltage.


    Option 2: tgFX $130
    TinyG board ($130), with integrated DRV8825 drivers = US$130 system with embedded 2.2A/45V drivers, PC required.
    :: Pros : USB connection to PC; more powerful processor than Arduino (I think); can have more than 3 axes; smoother movements than GRBL.
    :: Cons : More expensive; embedded drivers could be a problem if blown.
    [​IMG] TinyG

    Option 2b: [$105 Upgrade of Option 2: Driver upgrade] $235
    Option 2 ($130) + replace the Pololu-style drivers with offboard Massmind.org THB6064AH drivers (3x $35) = $235
    :: Pros : Good drivers for the price; Can be done later to minimise up-front costs.
    :: Cons : Requires some electronics knowledge to work it out; not sure if the TinyG can handle the voltage; the
    embedded drivers become unnecessary extra cost.
    [​IMG] THB6064AH


    Option 3: Linux CNC $133
    CNC4PC "C10S" breakout board ($28) + 3x Massmind.org THB6064AH drivers (3x $35) = US$133 system with 4.5A/50V drivers, PC required.
    :: Pros : Good drivers for the price
    :: Cons : C10S requires a PC with a serial port; complex software; drivers are kits that need to be assembled.
    [​IMG]C10S

    Option 3b: [$75 Upgrade of Option 3 : embedded mini-PC] $208
    Option 3 ($133) + Beaglebone Black mini-pc ($45) + Xylotex BBB_25 shield ($30) = US$208 system with 4.5A/50V drivers, no PC required.
    :: Pros : Can be done later to minimise up-front costs; removes need for extra PC; and resolves the parallel port problem; minimises footprint.
    :: Cons : BBB for CNC still in early development so might be difficult to set up.
    [​IMG] [​IMG] Beaglebone Black + BBB_25 shield


    Option 4: [Linux CNC on embedded mini-PC] $220
    Beaglebone Black mini-pc ($45) + Probotix "PBX-BB" breakout board ($70) + 3x Massmind.org THB6064AH drivers (3x $35) = US$220 system with 4.5A/50V drivers, no PC required.
    :: Pros : Removes need for extra PC; and resolves the parallel port problem; minimises footprint; PBX-BB looks like a well featured breakout board.
    :: Cons : BBB for CNC still in early development so might be difficult to set up;highest upfront costs.
    [​IMG] Beaglebone Black + PBX-BB


    Option 5: [GRBL at first, Linux CNC later] $92 + $133 or $208 or $220
    Start off using GRBL with Option 1, then upgrade to Option 1b, then switch to LinuxCNC with Option 3/3b/4.
    :: Pros : Low initial costs; learn the basics on a simple system; progressive upgrades so costs are spread over time.
    :: Cons: By the end of the upgrade cycle I will have an unused "Option 1" set left over... though that might be a good excuse for another project! :)


    Options considered but decided against for various reasons :
    Mach3 CAM software: No thanks, I'm through with Microsoft. This means that Smoothieboard Smoothstepper, and all the USB breakout boards are also out. [EDIT]
    Otherplan CAM software : OS-X only. I'm prepared to consider it, but given that I want to eventually upgrade to an embedded PC solution like the Beaglebone, I think that Otherplan is unlikely to fit well.
    Gecko G540 breakout/driver package: Very nice, but too pricey. Maybe later...
    Other drivers like Probotix 7.8/4.2/2.5, Keling 5042/5056/6050, Xylotex 3-in-1 / 4-in-1, STMicro L298N/ST6472, Linistepper. All considered, but I think that the when considering the "Amp*Voltage/Cost" ratio, the DRV8825 and THB6064AH drivers come out on top.

    So that's it!
    Please add your comments/thoughts to this overall plan, as well as my electronics and software options. As a guide, my preference is to spread costs out over time when it comes to upgrades. I would also prefer to work with a single CAM software rather than learning one and then switching to another, though you think there's only minor differences then let me know. Finally, my old spare pc doesn't have a serial port, nor does it have place to add a card to the motherboard, so my preference is a non-serial port solution, although I could buy an old pc without much cost/trouble.

    Some final questions I am yet to figure out:
    :: How much more complicated is the learning curve for LinuxCNC compared to GRBL or tgFX?
    :: Are controllers / breakout boards restricted by what driver Amperage/Voltage they can handle? (ie, are Options 1b/2b even possibilities?)
    :: Assuming I match my stepper motor choices with the max rated Amps for my drivers, what Voltage/Amperage power supply is correct for (3x)DRV8825 2.2A/45V drivers, and (3x)THB6064AH 4.5A/50V drivers?


    Some links:
    DRV8825 driver : http://www.pololu.com/product/2133
    THB6064AH driver : http://www.piclist.com/techref/io/stepper/THB6064/index.htm
    CNC4PC "C10S" breakout board : http://www.cnc4pc.com/Store/osc/product_info.php?cPath=33&products_id=696
    Probotix "PBX-BB" breakout board : http://probotix.com/index.php?view=product&path=16&product_id=204

    What about my physical design?
    I haven't got too far on this. I do know that I will be using v-Slot extrusion and solid delrin wheels, and hopefully some cheap-ish c7 ballscrews (I have one 500mm already). I am split between a movable x-axis gantry (preferred) or a fixed gantry and a movable x-axis bed, but will ultimately make my decision according to the size of ballscrews I am able to obtain, and whether a fixed gantry setup will still leave me enough usable area to create side plates for a larger machine.

    Thank you all for your help!
     
    #1 Agamemnon, Apr 25, 2014
    Last edited: Apr 26, 2014
    Mark Carew likes this.
  2. bhalkett

    bhalkett Journeyman
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    I just want to point out that Smoothieboard does not require a pc. It has Linux drivers (http://smoothieware.org/linux-drivers). It can also run completely host (pc) free using a sd card (http://smoothieware.org/sd-card).

    I've been "playing" with beaglecnc (Beaglebone Black running LinuxCNC) lately on my current cnc router. It seems to work well though it's a bit harder to configure that the full flown LinuxCNC running on a "full" computer.

    Cheers,
    Brian
     
  3. Agamemnon

    Agamemnon Well-Known
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    Hi Brian,
    Thank you for that correction! I was actually trying to refer to the Smoothstepper (which I believe is Windows only), but got my wires crossed (ha) over the name similarities. I actually think i've had them crossed for a while, having read about smoothstepper first, and then always dismissed the smoothieboard thereafter.

    Thanks - I will now look into this as another mini-pc option :)

    PS: If you are ever inclined, I would be very interested to read about your experiences with the Beaglebone Black and CNC. What hardware setup did you use, what challenges did you encounter, and do you see it as a way forward? I have read a very small amount about the BBB's PRUs, and how useful they aparrently are, so am also wondering if you had to do any tweaks (some python scripts?) to get them running / optimised. Food for thought in my brain anyway :)
     
  4. andrew

    andrew Journeyman
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    I considered a few of these options and went with the TinyG. It took a few hours to find the right combination of firmware and tgfx build and set the configuration. Now I'm working on interfacing it to my spindle controller. I'm happy with the choice so far.
     
    Ed Betlinski likes this.
  5. steelspinner

    steelspinner Well-Known
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    The Massmind drivers are pretty good. I have been testing one for while. The only downside I have found is some mid range motor resonance/noise. I have used the Smoothstepper in the past, it is a great unit and works very well.

    Another option for you might be a Kflop and Kstep. They are a little bit more expensive ($250 for the Kflop, $199 for the Kstep) but they are VERY configurable and have a lot of features that other motion controllers in the same price range don't have. The selling point for me is being able to put encoders on the axis and have a true closed loop system (no lost steps).

    Link: http://www.dynomotion.com/KFLOP.html
     
  6. Agamemnon

    Agamemnon Well-Known
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    Th
    Thanks for the feedback and suggestions. I have heard of Kflop though hadn't considered it initially because of uninformed expectations about price. After my research I've come to understand it could easily end up in that ballpark so I'll go back and have another look.

    For anyone who may be going down the same pathway as me, here's something I've learnt recently:
    High driver amperage is important for high performance, but don't forget to match up stepper ratings too. Steppers perform best when driver amps are equal to or exceed the stepper amp rating - and are limited by this too. Limitations: a driver rated and running at 2A running a stepper rated at 4A will only be able to get 50% of the steppers rated torque. The other way around is fine :)
    What's the implication? If starting off with weaker electronics, but thinking about buying big steppers to cater for future upgrades, be warned...
     
  7. steelspinner

    steelspinner Well-Known
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    Something else to keep in mind with the stepper motors is that bigger isn't always better. You have to look at the phase inductance. Higher induction results in a faster torque curve drop off (lower usable rpms). Generally the smallest motor that will work for the needed torque with the lowest phase inductance will perform better that larger overkill motors. The inductance that you should be looking for will be below 2.5mh ideally below 1.8mh. With inductance higher than this the usable rpm range drops drastically.

    Don't forget voltage. The higher voltage you run the higher the usable rpms. Ideally you should run your motors at: V=32 x sqrt(motor inductance). This usually ends up being higher than most drivers can handle, unless you get high voltage drivers. This allows the best motor performance without over heating. Stepper very rarely run at full amperage and only for very short period of time. Driver current is important but correct voltage will give much more noteworthy real world performance.

    Watch out for high torque for size (ie. nema 23 motors with >400 in/oz), they generally have a very low torque drop off, rpm wise, due to high inductance. They are fine for slow speed operation but anything above about 150-200 rpm have almost no torque unless you run them at very high voltage. High voltage drivers can get pretty expensive. Also, larger motors have a larger rotor inertia. This means slower response to speed and direction changes: meaning higher voltage for the same performance.

    IMHO, you should look at wattage needs of your machine. (Watts = IPM * Lbs / 531) Lbs is the weight of the heaviest thing you have to move, including cutting force. If your system needs 100 or less watts use a stepper motor. This usually falls in the nema 17 to mid sized nema 23's. Watts between 100 and 200 can be a stepper motor or a servo. The usable motors would be mid to large nema 23's. Higher than 200 watts USE SERVOS. Large steppers generally have very poor performance (for the reasons I said above).

    A good source for info about stepper drivers is: http://www.geckodrive.com/faq.html

    They make EXCELLENT products. Not always the best for every machine but very, very good.
     
    andrew and Agamemnon like this.
  8. Agamemnon

    Agamemnon Well-Known
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    Many thanks - looks like a stack of good advice! Certainly will be something I factor in to my final decisions.
     
  9. steelspinner

    steelspinner Well-Known
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    I'm sure you will find what is right for you. :thumbsup:
     
  10. andrew

    andrew Journeyman
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    steelspinner - Great post!
    The rating on these things can be confusing even for someone with a background in motor operation and theory. To make things worse, a lot of sellers don't give you these numbers. Oriental Motor Company (stepperonline) is one place that will give you those numbers. I'd recommend them if you really want to find the right motor with these calculations. -I have no affiliation with that company.-
     
  11. Ronald van Arkel

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    @Agamemnon: Useful first post, thank you for that, it gave me a start.

    @All: I've been looking around for a more powerful solution than an Arduino and use an Intel Galileo instead; This board has more options for I/O like a RJ45 connected network controller AND even space for a mini-PCI card that could be used I think (not sure) for a Solid State Drive (mSATA). It also has a 400MHz 32bit CPU that is capable to run Windows or Linux directly plus it has a natively much more calculation power (floating point), read could be smoother to control our CNC projects, compared with the Arduino. It is pincompatible with the daughterboards of the Arduino (3.3 and 5.0 Volt) so that's not a problem, but I´m looking for software... I'm more a computer guy and love to work with Windows in compare with Agamemnon :D, I'm here if you need help on computers by the way!

    Ive found this so far:
    http://forum.conceptforge.org/viewtopic.php?f=6&t=95
    And will keep looking and updating when I've found more options!:brb:

    I know there is the BeagleBone Black, based on an ARM CPU.
     
    #11 Ronald van Arkel, May 9, 2014
    Last edited: May 9, 2014
  12. Agamemnon

    Agamemnon Well-Known
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    Np :)


    RE : Software
    Well, the first thing that comes to mind is definitely Mach3. That certainly appears to be the go-to software for the Windows platform, and there is a ton of information out there to assist with setting it up / troubleshooting. It looks pretty good, though the downside is that there is a cost for the software.

    RE: Hardware / Intel Galileo
    The primary difference between the Arduino setup vs Mach3 (or LinuxCNC) is that the PC hardware itself is used to send signals to the breakout board and drivers. So, I'm not sure that the Arduino daughterboards would even be required for use with the Galileo, so long as the Galileo was running Windows and you had a basic breakout board. Ie. "Option 3" from my original post would probably work fine, though not 3B.* You would need to use the mini-PCI card slot to install a parallel port interface for the C10S breakout board, as I doubt the Galileo has one. The upside about using Windows though, is that a number of other breakout boards out there support USB interfaces to Windows, so that opens up your options a lot and could mean you can avoid the PCI card requirement for the C10S.

    * I say not 3B, because the Beaglebone is essentially a replacement to your laptop/desktop/Galileo, and as far as I know there's no Windows / WinME / virtualising hacks that will work with it. But Linux will, <nudge! nudge!>, and even with a pretty GUI in case youre concerned about command line voodoo. :)
     
  13. Mark Carew

    Mark Carew OpenBuilds Team
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  14. Ronald van Arkel

    Staff Member Resident Builder Builder

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    After 4 weeks the lost son is back :blackeye:.

    I was breaking my head on building a Spanish version (for Mexico) of OpenBuilds... :spam:

    Any way, the Galileo isn't supported by most "do-it-yourself" projects and almost no one talks about it on several forums, so, forget that one for now.

    The Beaglebone is a good option indeed, lots of free information and software, fast as well and a lot of daughter-boards.

    But, I've been looking at the ones Mark is pointing out, the ones that you can find in the OpenBuilds part store. Those boards have all you might wish for; I like personally the MKIII but a MKII has all that I need especially when I'm going to build a router. But, it uses Windows (no Linux/Android plans are made by them) so that's a no-go for you... or?

    Now, I do like a good Linux GUI but I'm okay with voodoo too ;). (and no bling needed as long as it's stable and can be upgraded (no problem, I know)).

    I'm waiting for the steppers to come in so I can place my first order, for an OX, on OpenBuilds WITH an MKII!:thumbsup:
     
  15. Robb

    Robb New
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    Has anybody looked at running linuxcnc on a udoo quad board? Will it even work? My 750 x 100 Ox is using a tinyg controller, and use my Mac for tgfx and am getting ready to try vcarving via VMware on a windows 7 guest VM.
     
  16. Agamemnon

    Agamemnon Well-Known
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    Good to see the OpenBuilds magic is spreading!

    As for controllers, I'll check out the OB MKII and MKIII, though I would still prefer a linux option instead of windows. At the end though, any OS will be fine so long as the system performs!

    To that end, I've been working backwards from my electronics decision tree, to determine exactly what current drivers I require, and thus have been spending a large amount of time working on a force/inertia/torque/power spreadsheet, in order to determine exactly what stepper I need. I know there's lots of rough estimate ways of working out the stepper size, but I like to know the "why", and this had led me down a whole new rabbit hole! Interesting outcomes though. I'll post the spreadsheet once I've finished it. Out of interest, what steppers did you order?
     
  17. Ed Betlinski

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    @Agamemnon Thank you for your insightful analysis of the different controls. I too have been scratching my head trying to figure out what to use with my OX build when I get the parts and start building. Being retired I thought I should learn how to use grbl, but have been learning Linux for the past few months and LinuxCNC is also of interest. I don't like the idea of a desktop computer with a parallel port to run it or Mach3 for that matter. I also like the idea of a small, complete controller, I think they call it an embedded system to eliminate the desktop computer.

    I saw an Instructable of a RaspberryPi Alamode CNC Controller, which made sense and looked great. However, many people advised me that the Pololu drivers were not strong enough for the Stepper Motors OpenBuilds supplies. Then I ran across one of your options of a BeagleBone Black with a cape for the system. Not being particularly strong in electronics, I kept researching this and found the following:

    1. The new Rev C of the BBB now has 4GB of eMMC which is also faster and comes installed with Debian.
    2. A gentleman by the name of Charles Steinkuehler at blog.machinekit.io has developed a 4GB SD card for the BBB with LinuxCNC.
    3. BBB will now run LinuxCNC.
    4. There are many capes made for the BBB, some for 3D Printers and some for CNC, including some with Parallel ports. Listing at blog.machinekit.io/p/hardware-capes.html.
    5. You could plug this into external drivers or kits purchased on ebay or amazon, to drive stronger Stepper motors and still run LinuxCNC from the BBB.

    Unless I am completely missing something, I think this can be developed into a compact complete controller for not only the OX, but also a 3D Printer or other OpenBuilds project. There are small LCD screens to incorporate into the controller along with small wireless keyboard and mouse. I have checked the Adafruit web site and they list quite a few variations. There is even a cape called the Rosetta Bone which can run grbl and LinuxCNC with a Ramps board or Cramps Board that Charles Steinkuehler developed, for the smaller Stepper Motors running maybe a Lazer cutter or engraver.

    What I would like to know is if this makes sense and would be a good way to go. You mentioned the cost in your write-up. Does it become more cost effective without the need for a desktop computer with a parallel port? I am looking for as much input as I can get before I make the final decision to buy the parts. Any input would be appreciated.
     
  18. Agamemnon

    Agamemnon Well-Known
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    Hi Ed,
    Glad that this discussion has helped generate some ideas.

    I agree that life would be better with a self-contained electronics system, which is why I thought the Beaglebone (or something like it) would be a good choice. I researched a number of similar mini-pcs, and settled on the Beaglebone Black as the preferred choice, primarily because there's been a decent amount of CNC-related work on it already, but also because the BBB a PRU (Programmable Realtime Unit) which is perfect for CNC. Rev C makes it even better, and at its price point its simply fantastic.

    In my write-up above, I'm assuming that people are going to be using a cheapo second-hand PC, preferably with a parallel port included, but otherwise with a parallel port card added ($30, maybe less). There's lots of old PCs available these days, usually for next-to-nothing. If, however, youre thinking that you need to buy a new PC just for these purposes then I would definitely be looking at a BBB instead!

    When it comes to controller units, I think it really comes down to how many volts they can pass through to the driver, and how many volts and amps your drivers can handle. With stepper motors, more volts = more speed, and more amps = more torque. As stated above, the watts generated by the motor are worth considering as your overall gauge, because Power (Watts) = Voltage (Volts) * Current (Amps). Calculate how much torque and speed you require, including figuring out drive type and drive lead, then get an estimated wattage required, then use this to figure out your driver requirements (Amps / Volts), then find a motor that matches these requirements. I have a big spreadsheet in the works that will give you some comprehensive figures and calculations, without the brainwork. Watch this space!
     
  19. andrew

    andrew Journeyman
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    Good thoughts Ed and Ag. The beaglebone is a sweet piece of kit. Should be the perfect "heart" for cnc controller. I just couldn't find the right combination of other bits (hardware and software) to make the complete solution.
    I went for the simple usb tinyg controller, so I can give some thoughts on that. The hardware is nice. A single board has what you need, and I just plug in a netbook. It provides for a 12v fan, spindle ppm, coolant, limit switches, etc. Drivers are on board (not modules). Good chips. The firmware has real nice motion control algorithms. I thinks it's built off grbl with a bit more processor to leverage. The gcode sender should be the simplest part, but it falls flat. For me at least. It's all java, and I hate java. The thing has bugs and memory leaks galore. I've tried windows and linux. So, I wrote some shell scripts to shoot the gcode, but the details of the flow control are more complex than you would expect. So, it's working for me but I don't have a nice jog interface or a proper feedhold implementation. I don't think I could recommend it right now.
     
  20. Ed Betlinski

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    @Agamemnon Thanks for your thoughts. I did look into a parallel port card for my computer, but I didn't like the idea of a big desktop computer which more or less anchors me to one spot. I was thinking more on the line of a laptop or netbook, whick could be moved easily with the CNC router, which is why I was looking for an "All in One" style Controller with the BBB. Thanks for reminding me about Ohm's Law. My Physics Prof spent a year pounding it into our heads and now I didn't have the sense to check it out. I guess that after 40 years or so I could get away with it. I will watch for your spreadsheet. Thanks
    @andrew I read a lot about the Tinyg and some people are very passionate about it. I just never thought it would fit the need for a CNC router as I mentioned in my original query. Besides, I learned the hard way that if there is a chance for something to blow, the driver, it should be easily replaceable. On the Tinyg or the gShield for that matter, the drivers are soldered to the board and if they go you either have to replace the whole board or de-solder the driver chip and solder on a new one. That was always the beauty of the Ramps board with the Pololu drivers. The drivers didn't cost that much and could be easily replaced. Your comments about this board justify my thoughts about it. Of course they do say it is still under development on most websites that sell the unit.
     
  21. Agamemnon

    Agamemnon Well-Known
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    @Andrew Thanks for your contribution. I really like the look of the TinyG, particular its smoothed move profile algorithm. Unfortunate that there's programming problems in the interface! Is it tgfx that is generating the java errors? I came across this forum post regarding external interfacing options using a terminal emulator (COOLTERM): http://www.shapeoko.com/forum/viewtopic.php?f=26&t=506&start=10 - have you tried that? What are your scripts written with? I've seen some stuff on the net about Python interfacing with grbl, and would definitely be looking to do the same with TinyG if thats an option.

    @Ed I looked into the TinyG wrt using external drivers, and it is possible use them. This means that you can use different drivers if required, or wire in extras should the built-in ones get blown. Personally, I think this option is really important, otherwise I wouldnt consider this as an option at all! If you search the Synthetos website you will find the specifics of how to set this up.
     
  22. Zootalaws

    Zootalaws Veteran
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    I like the idea of the TinyG, but the 2A limit means it's really only suitable to the hobbyist.

    I would like to make CNC a part of my business, but finding the right combination of kit is proving difficult. The stepper-motor vendors have decent priced drivers suitable for up to 4.5A, but they are an unknown quantity, based on Toshiba chips.

    The boards with good software functions seem to have a limit on the power you can put through them.

    So, high power and good support - that seems to be missing.
     
  23. Ed Betlinski

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    @Zootalaws I had a number of questions and the answers I got here generated more, which led to more research and more questions. So I decided that since I am planning to build a few units, i.e. CNC, Laser Engraver/Cutter I would buy a few different controllers and try some different types to determine which performs best. I am retired and have the time to do this, but am still waiting for my parts to be delivered. The electronics has come in, but not the machine parts.
    In general though, I will be using grbl. I liked the idea of a TinyG but didn't like the low Amp restriction BUT @Agamemon mentioned I could use EXTERNAL DRIVERS with the TinyG and he is absolutely correct. This means the low amp max on the board is not a problem. All this is documented in the WIKI on the TinyG and I am so glad he pointed it out to me because the more I look at the TinyG the better it looks. In doing more research, other people have just come up with other alternatives, which look good. Peter van der Walt has developed a small board that plugs into a Raspberry Pi and is working with AndrewHodel who developed GRBLweb to control the CNC process with the GrblPI CNC Control Board. Details at http://wiki.openhardware.co.za. Both these guys are contributors on the DIY CNC "How 2" and DIY CNC Communities on Google+. And Andrew has a You Tube video on GRBLweb.
    Another development that caught my eye was from John Lauer with a program to control the CNC through the TinyG called ChiliPeppr TinyG Workspace. There is a You Tube video by the same title explaining what it does and it looks good. There are a lot of add ins for this program such as the Braid Gcode File and JSCUT.
    Unfortunately, I don't yet have a machine to try these out on so can't tell you from first hand experience. All comments and the videos look favorable so I can't wait to try them.
    Another item that just got my interest is that a new version of FreeCad is out and has the ability to generate gcode you could write to a SD card. The write up spoke specifically about 3D Printing, but I think the gcode is the same - someone please correct me if I'm wrong. FreeCad is available in Ubunto Linux and should work with the Raspberry Pi.
    Things are changing so fast the if my parts don't come in soon I will be spending a lot more time researching the controls.
     
  24. Zootalaws

    Zootalaws Veteran
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    @Ed Betlinski, that's really helpful, thanks.

    It just happens that I have a bunch of MCUs, including RPi and some other dedicated Linux boards... I will definitely look at GrblPi and FreeCAD.

    I just noticed - we're neighbours ;) I'm on Borneo. You probably don't have the same problems with sourcing stuff that I do - still very much an agrarian economy over here, but with oil. So almost nothing in the way of machine parts or electronics - have to order everything in.
     
  25. Ed Betlinski

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    @Zootalaws Hi Neighbour. I forgot to mention that I also researched the Beaglebone Black, which I like a lot and found the following.

    1. The new Rev C of the BBB now has 4GB of eMMC which is also faster and comes installed with Debian.
    2. A gentleman by the name of Charles Steinkuehler at blog.machinekit.io has developed a 4GB SD card for the BBB with LinuxCAD.
    3. BBB will now run LinuxCAD.
    4. There are many capes made for the BBB, some for 3D Printers and some for CNC, including some with Parallel ports. Listing at blog.machinekit.io/p/hardware-capes.html.
    5. You could plug this into external drivers or kits purchased on ebay or amazon, to drive stronger Stepper motors and still run LinuxCAD from the BBB.
    6. Problem with the LinuxCAD is that you still need a parallel port or a parallel to serial board.

    At least with the FreeCad it runs on Ubuntu (just like LinuxCAD) and I believe Ubuntu runs on RPi. That way you could run it on the Pi and use the Arduino Shield to run the motor drivers or interface the RPi to the TinyG. Now you have all controls in one package. You may even want to add a laptop HDD for storage as some have who set the RPi up as a Home Server. There is also a Great Instructable explaining how to set up a RPi Home Server with a HDD. Check out www.instructalbes.com under Ultimate Pi Home Server.

    My intention was to get away from using a desktop Computer and use the CNC controller for everything. There is a GREAT Instructable called Raspberry Pi Ala Mode for CNC Control, which uses the ala mode board that connects to the RPi. But some people in the Google+ community advised me against using too week a motor driver for the CNC. Some said it was OK for a 3D Printer, but not a CNC. This led me to my other searches.

    I already have two RPi's and an ala mode board and a TinyG, in addition to an Arduino Uno, Due and Mega. So as you can see I can go a number of ways. I'm having trouble getting a BBB here, but I can order one in the US and have it sent to my brother and he can send it to me. I can easily have boards made here, which I think I might do for the GRBLPi CNC Control Board I mentioned in my last posting.

    I too have a difficult time sourcing stuff here. Most items here are copies and are inexpensive when made here. Most Filipinos don't have a lot of money so stores don't stock the high, or even medium priced components and there are lots of copies. But the copies are good and reliable. And the stuff I order from China or the US takes 3 months to go through Customs before I get it. I shouldn't complain too loud or it will take 4 months. :) Keep in touch. As I start building I will let you know how it is going, but it may take a while.
     
  26. Zootalaws

    Zootalaws Veteran
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