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?) 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. 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. 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. 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. 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. 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!