Largest Milled PCB yet? - Page 1
Forum section: electronics / projects

author: JanTheVan
author_rank: Newbie
timestamp: January 04, 2019, 07:13:53 pm
content: Well it feels like it could be, given the amount of time it has taken me!My ears are ringing, but the result, I think, has come out pretty well! Its not been without pain though, oh no! Wrong feed rates, bad quality cutters, snapping milling bits and the one that almost pushed me over the edge, and scrapped the 2nd attempt, WINDOW AUTOMATIC UPDATE! Yep, 3 hours in to the job, all looking good, windows decided to do an update and shut the PC down! That took a large glass of wine to get over.All in all it took about 10 hours to mill and drill, about 3 days to get the process sorted from start to finish, so pretty good, the size of the board is 8" X 12" and its double sided. I'll follow up here with a detailed how-to for people that want to give it a go themselves, until then, I've attached a few pictures of my board. Enjoy!Scott

author: xyrtek
author_rank: Regular Contributor
timestamp: January 04, 2019, 07:30:37 pm
content: Whatever it is you are doing you are doing it right, those look great, well done!!!

author: Bud
author_rank: Super Contributor
timestamp: January 04, 2019, 08:08:54 pm
content: Awsome, worth framing and hanging on the wall !

author: soldar
author_rank: Super Contributor
timestamp: January 04, 2019, 08:23:19 pm
content: Two words: spec tacular!

author: coppercone2
author_rank: Super Contributor
timestamp: January 04, 2019, 10:21:55 pm
content: wow that is slow. if i had to do that i would work on my etch tank again.it kind of sounds not worth it given the noise.

author: james_s
author_rank: Super Contributor
timestamp: January 04, 2019, 10:27:47 pm
content: While the results do indeed look great, I have to wonder if 10 hours of milling and drilling is worth it. I like the idea of CNC drilling but the etching part could be done in 20-30 minutes using photo resist or toner transfer. That board is similar in size to the largest ones I've etched at home and the result was similar although your drilling is obviously neater.

author: janoc
author_rank: Super Contributor
timestamp: January 04, 2019, 10:28:29 pm
content: Well done! However, this is pure masochism and throwing money out of the window, IMO. Photolithography + etching it would have been much faster and cheaper (never mind the dangerous dust!), then just use the CNC to drill the holes.And are you really running your CNC from a general purpose Windows machine (since auto updates are enabled)?! You are really begging for pain there.

author: David Hess
author_rank: Super Contributor
timestamp: January 05, 2019, 02:18:00 am
content: Configure the network interface to a metered connection to stop Windows from downloading updates until you do it manually.

author: beanflying
author_rank: Super Contributor
timestamp: January 05, 2019, 02:40:40 am
content: Excellent work on a huge slab of boardLove to have some more info on bits used, feeds and speeds if you could

author: coppercone2
author_rank: Super Contributor
timestamp: January 05, 2019, 11:00:14 am
content: what machine did that/

author: KL27x
author_rank: Super Contributor
timestamp: January 05, 2019, 10:39:32 pm
content: QuoteIf you are gonna drill the holes with CNC, you should generally do that first, then apply the etch resist, so's you can line the resist to the holes. It's a lot more anxiety the other way round.

author: voltsandjolts
author_rank: Unknown
timestamp: January 05, 2019, 10:54:26 pm
content: Is it actually worth owning and running a PCB mill in these days of cheap proto PCBs?According to pcbshopper.com, JLCPCB could make 10 of these double sided 200x300mm boards delivered to UK for GBP71 in 6 days.With real vias. And solder mask. And silkscreen.

author: beanflying
author_rank: Super Contributor
timestamp: January 05, 2019, 11:25:57 pm
content: Quote from: voltsandjolts on January 05, 2019, 10:54:26 pmIt is a prototyping 'option' a more typical board would be under maybe an hour turnaround. Apart from the Vias needing more manual work, silkscreen and solder masks do little for a hand assembled prototype board. Make it and decide you need to add a few more bits or tweak a trace and do it again within an hour.By then you have saved time (commercially this can be lots of $$) and got the project done so the designer and 'team' in some cases can move on when it works instead of maybe juggling several projects waiting for a board. When you have the design right then you can send it off to whoever you like.Mine gets less use now for PCB's due to cheaper small commercial lot availability and my timeline isn't an issue for most jobs. It was getting more use in timber or plastics for my other toys prior to getting a LASER and a few 3D printers.But they still have a place IMO.

author: james_s
author_rank: Super Contributor
timestamp: January 06, 2019, 12:33:40 am
content: I don't etch boards at home very often, but it's still a useful ability to have. If I need a one-off prototype I can go from CAD to a finished ready to assemble PCB in under an hour including all the setup and cleanup, even expedited processing and shipping it's gonna be several days wait to send it out, and a lot more expensive.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 06, 2019, 02:04:24 am
content: Quote from: JanTheVan on January 04, 2019, 07:13:53 pmpcb mill is a one time process, keep or trash... i've built a prototype before (its been 2 years now from the youtube date tag, its still under "alpha test" duh) to etch resist ink. the "mill" bit is just a pogo pin, anything wrong (usually missed steps) i can right away see and cancel process, board can still be reused all i have to do is add resist ink to the incorrect etched area and reprint, the same machine will also be used for drilling, just change bit, its a "Bethan" machine (BEtter THan hANd)...the latest build is 10 x 20 cm PCB, it took 2-3 hours or so iirc due to some broken 3d printed part, i have to reprint 3-4 times (before realizing something broken) on the same board before getting the right result, if not because of that, i think 1 hour most is all it takes including copper ething and correcting (manual knife cutting) the shorted traces. for double sided, i use special method for alignment, no need overblown excess area (where the pcb side area will cut off and trashed). ymmv.

author: cdev
author_rank: Super Contributor
timestamp: January 06, 2019, 03:12:29 am
content: WOW, thats just spectacular. I hope you are planning to protect it well under a good conformal coating

author: james_s
author_rank: Super Contributor
timestamp: January 06, 2019, 05:42:45 am
content: I used to trust Windows Update completely and for years it was a very useful service. Starting when they started pushing Win10 though it went downhill real fast and became in my mind a threat more serious than the threats it was meant to prevent. With Win10 consumer versions this is even worse and the automatic updates that happen without user consent are completely unacceptable. I turned off all updates ~3 years ago and everything has worked so much more smoothly. A computer should never *ever* reboot without my express permission.

author: David Hess
author_rank: Super Contributor
timestamp: January 06, 2019, 01:30:12 pm
content: Quote from: james_s on January 06, 2019, 05:42:45 amIt has only gotten worse despite Microsoft's lying assurances since it became a problem. So far I have only needed to set the network configuration to "metered" to prevent inopportune updates and reboots.I become very unhappy the first time a weeks worth of possessing time was lost. Are people expected to even do work on PCs anymore? I hope every person at Microsoft who thought this was a good idea gets lynched.

author: beanflying
author_rank: Super Contributor
timestamp: January 06, 2019, 01:47:28 pm
content: Much as they a PITA at times the typical 3D printer choice of Micro SD cards loaded with G Code beats having a PC hooked up to the machines especially when you might have one running for 10-20 hours on a job.Time for CNC router controllers to go the same way add a bit more brain and a simple interface for jogging etc. and lose the PC from being tethered as a data storage device?

author: janoc
author_rank: Super Contributor
timestamp: January 06, 2019, 01:58:41 pm
content: Quote from: beanflying on January 06, 2019, 01:47:28 pmA better solution for 3D printers is stuff like Octoprint or Astrobox - Raspberry Pi loaded with the front-end software, so that you can access, monitor and control the machine remotely. But there the Pi isn't driving the stepper motors, only feeding the G code to the integrated controller (often some Arduino-like board). Mostly saves running around with the SD cards and saves you from having to sit next to the machine babysitting it while it works because it supports cameras - so you can watch it from elsewhere in the house.And for cheap CNCs where there is often only a "dumb" controller that needs pulses for the steppers (often using parallel port!), there is e.g. Linux CNC or Mach 3 - put it on a small dedicated Linux computer and problem solved. Way more stable than relying on your Windows PC/laptop to keep going for many hours straight.Of course, if you have money (and aren't afraid to mess with the wiring), there are dedicated CNC controllers too.

author: beanflying
author_rank: Super Contributor
timestamp: January 06, 2019, 07:05:27 pm
content: Adding a PI is not a better solution to a 3D printer it does nothing to useful to the G code in terms of the print itself and is not required by the printer to operate. The apps watchdog like functions are of some use but lack in what I want for enclosure control so I will be going somewhere different for mine. A $30 wifi camera looks after my three printers if I want to take a look and at this stage I will be staying with cards for data. My previous post was background to what can be done without attached PC's or additional micros with simple boards.Adding this sort of functionality to the cheaper or home brew CNC routers needs to take some leads from the 3D printer manufacturers. There is a few forks of Marlin for linking RAMPS style boards in existence but I haven't looked into them much but as far as I am aware they still use a PC in the loop, this is the link that needs severing. PC's are as you point out not needed nor is even a LINUX board what is needed is a simple G code interpreter with some setup controls and interface and the processing needed is no more complex than 3D printers.My bigger router which I got secondhand with a PlanetCNC board already fitted is getting it's own dedicated mini PC to drive its controller with Windoze auto updating as removed as possibleThe industrial end of the market is another whole can of worms and getting well off topic.

author: janoc
author_rank: Super Contributor
timestamp: January 06, 2019, 09:35:06 pm
content: Quote from: beanflying on January 06, 2019, 07:05:27 pmAnd what "useful things with the G-code" do you want the 3D printer controller to do? (apropos, Octoprint can actually slice models for printing but doing that on a Pi is quite a masochism).The idea of Octoprint and similar is to add convenience to the machine, nothing else. If your machine has such functionality built-in, then you really don't need it (some printers actually do already) but many don't. My Mendel90 can work from an SD card and can have an LCD + encoder/button connected to it (it doesn't come with one - it was a kit printer) but I still much prefer being able to upload the ready to go G code from my "CAD" PC to the machine over the network instead of messing with cards and then the limited UI offered by the printer.If you don't find that useful, fine but I think a lot of 3D printer users will disagree with you there.Quote from: beanflying on January 06, 2019, 07:05:27 pmActually Marlin and RAMPS are a fairly terrible solution (even ignoring the design and manufacturing problems some of these boards are notorious for). Those boards are being pushed to their limits by the 3D printers already because the 8bit ATMegas on these are not exactly speed demons when it comes to the math necessary for calculating the movements. There are plenty of printers on the market which "outrun" their controllers - are capable of higher printing speeds than what the poor Arduino-compatible RAMPS board there can computationally handle.I don't see something like RAMPS being able to drive some serious motors you would find on a CNC neither, the typical "Stepstick" style drivers stuck in female pin headers these boards use simply wouldn't be able to handle the currents. Some poorly designed boards struggle even with the common NEMA 17s already, losing steps or going into overtemp shutdown on the drivers - making you lose your print in the process. Also if your CNC happens to actually use servomotors with encoders, you are out of luck, because most boards targeting 3D printers don't have any support for them. Though I believe there is at least a variant of Marlin (or perhaps GRBL) firmware that allows closed loop control if you want to make your own board.There are more modern and better boards around - e.g. Smoothieboard (some list here:http://3daddict.com/32-bit-3d-printer-board-comparison/) but those generally solve only the math slowness part by using a beefier MCU (typically some ARM), not the other issues. Those don't matter on a 3D printer but may be a problem on a CNC mill.

author: Kilrah
author_rank: Unknown
timestamp: January 06, 2019, 10:28:31 pm
content: Quote from: David Hess on January 05, 2019, 02:18:00 amEven better, flip the "don't update for a month" switch...

author: beanflying
author_rank: Super Contributor
timestamp: January 06, 2019, 10:49:14 pm
content: Quote from: janoc on January 06, 2019, 09:35:06 pmLeaving Octoprint/PI alone as it is off topic and will drag this thread further away from the OP's Post. It deserves it's own thread.We have been seeing the first 32 Bit boards getting around more and more over the last year or so, using 8 bit as some sort of a argument or point is what exactly? 8 bit apart from the bottom end of the market will be gone fairly soon IMO.Do not take the words I wrote and try to make them more than they were. I made an OBSERVATION that there were some forks of Marlin to Ramps boards that I was aware of in passing. I didn't suggest them as a solution just that people had done some work on it as I own a Laser Cutter in my tools I was interested in options when I first got it.Marlin is a fairly well developed and constantly evolving standalone interface to a CNC machine in the majority of cases it is 3D printers. There is no reason I can think of it couldn't be forked for example to a non ramps cnc router board in particular if done from scratch.At the Hobby end sizes (lets just pick 3020 and smaller) what is needed is a some modification toward a 3D printer standalone solution. Local Data storage, G Code interpretation, Interface for jogging, setup etc. You are making an assumption that the CNC board would use bottom end Chinese step stick drivers like the 5+ year old RAMPS boards to do this would be a really poor choice given what hardware is already in use and available now.So be it a Marlin, GRBL, Repetier or whatever firmware as a starting point time to lose the PC.When you leave the 3020 there is currently a large jump overall in requirements and purchase price and you are into the realms of Mach3&4 PlanetCNC etc. so likewise best left alone for another thread.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 07, 2019, 12:34:26 am
content: there is no use of super power mcu if the mechanic cannot handle the speed. once i speeded up my knock off prusa (the china master copy from where i learnt to build another machines at fraction of cost), but the result is poor print mainly due to mechanical reason iirc, so i slow it down. the atmega mcu has more time waiting than compute, i dont see any fault or jittery motion even on fast speed setting that can be narrowed down to mcu bottlenecking, i got a good GUI respond as well, no pause in motion. imho, faster mcu is mostly gimmick on better colorful GUI etc, but i maybe wrong, anyway my prusa works fine in term of mcu processing. the driver stucked in female header is not a good excuse to dismiss OSHW reprap/marlin/ramps as the header is meant to put the right driver on (extendible and configurable) if user see not enough current or missed steps, user should upgrade to bigger version motor driver and the motor, thats the idea instead of buying another new machine that costs another 3-10X. imho as a person who built some proto machines from scratches. i believe we can buy that cheap arduino + ramps shield board and then put another appropriate driver, motor and gearing system to lift a tanker.the earlier proto-bethan i showed is pretty much a standard OSHW reprap 3d printer build (arduino mega + populated ramps shield, except with different mechanism of and the short Z height and head assembly from 3d printed parts), no need to fiddle with marlin FW, just copy to mcu as is, use FlatCAM OSS to translate gerber to gcode and good to go. i only need to hack GCode for manual drilling process, ie the head will go to drill position (translated from NC Drill file), and then i will correct pcb position and hit enter (encoder button) and head will start drilling. alot better than looking at PC screen to find which hole position and then drill with freehand. 0.5 - 0.8mm drill bit and freehand dont work together nicely, i killed many bits before, before even successfully punching a hole.there is one word for faster mcu (even OSHW version), its "ex pensive". and close feedback loop motor system? few words... more more expensive than the expensive. a single stepper motor system including the close loop control board can cost few times than my prusa. let alone building complete system using 3 or 4 of that. imho CNC machine only suitable if people want to get serious in substrative CAM such as making mould, aluminium rf shield and enclosure or a some quality metallic pendant for SWMBO etc, but for scratching pcb? i dont think so. anyway a sure way to get a really working machine is go to Hitachi or Toyota factory and ask what CNC they use, buy that.

author: james_s
author_rank: Super Contributor
timestamp: January 07, 2019, 12:43:34 am
content: Quote from: David Hess on January 06, 2019, 01:30:12 pmI wish I could send them a bill for all the time I've spent fixing the issues caused by updates at a machine shop and vet clinic I'm indirectly involved with. Critical systems getting updated to a new OS before the specialized software they run is supported, updates that take place whenever they please, nevermind the fact that shutting down the system that processes payments or stores and retrieves digital xrays and medical data and locking it out for an hour or more at arbitrary times during the business day has a very real cost.I'm not one of those Linux fanboys but that's really starting to look like the only viable way forward. Not so much that Linux on the desktop is amazing, I mean it's ok but not without problems, but Windows has regressed in quality and usability to the point that I can no longer say that it's better. It's a shame too because IMO Win7 is superb, the pinnacle of MS operating system development. The very few issues it has are easily resolved, while 8 and 10 are incredibly user hostile.

author: David Hess
author_rank: Super Contributor
timestamp: January 07, 2019, 03:37:27 am
content: Quote from: Kilrah on January 06, 2019, 10:28:31 pmAnd then flip it again every month after? And if I forget, random data death? No thanks. Besides which, I have already caught Microsoft flipping it back just a day later.It is computers which are good for rote tasks, not humans. If the computer is delegating rote tasks to the human, then that is the opposite of productivity. Why is it again that Windows Explorer can no longer provide a directory sorted by folder size so I have to do it manually?XP (and I assume everything afterward) had its own set of bad behaviors. What happens when power is lost, so the UPS signals the system to shutdown because only 15 minutes of power remains, and the system responds by installing updates leading to an unplanned shutdown in the middle of the updates?Yea, I'm not bitter. Fuck you Microsoft.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 07, 2019, 08:53:25 am
content: Well complaining ms windows wont help anything, there is no better alternative productivity tools wise. You want 90's era dos command line of linux? talking to every productivity usb devices will require some sort of script no? How about everything upside down gui imac? No thanks. windows xp is still the king, nothing matches its file explorer, if i only have one tool, it will be it, all the next generation explorer vista to 10 are all toy... if i have security sensitive materials, i have the latest antivirus, or using proven encryption sw, so even if my system got hacked,all they get is garbage files. I make fresh install image, so next time my system got corrupted, 10 minutes is all it takes to get back all the fresh install sw. And continue work. its a matter of knowing and using the tool. if we have to complain about it then we are using the wrong tool. Ymmv. My protest is i will keep using xp until they make window the way it should be, at least better functionality and productivity compared to xp. But moving away from windows is not an option there is simply no other alternative.

author: Kilrah
author_rank: Unknown
timestamp: January 07, 2019, 09:32:20 am
content: Quote from: David Hess on January 07, 2019, 03:37:27 amFlip it again the next time you need guaranteed "stay on".But if you need that regularly just use group policy to set windows update to "notify only" like before.

author: janoc
author_rank: Super Contributor
timestamp: January 07, 2019, 10:48:23 am
content: Quote from: Kilrah on January 06, 2019, 10:28:31 pmThat doesn't actually work reliably and gets regularly reset by Windows. The "Home" version of Windows 10 doesn't even have this option (nor does it have group policy editor), you can only delay the installation of an update - and if you aren't quick to react, it will "helpfully" schedule a reboot for you automatically.

author: Kilrah
author_rank: Unknown
timestamp: January 07, 2019, 11:01:50 am
content: Quote from: janoc on January 07, 2019, 10:48:23 amYou can do it via registry edits (or there are tricks to enable the group policy editor).Clumsy yes, but possible.

author: janoc
author_rank: Super Contributor
timestamp: January 07, 2019, 11:11:02 am
content: Quote from: beanflying on January 06, 2019, 10:49:14 pmWell, you were talking about RAMPS. RAMPs is pretty much equivalent with 8bit AVRs, the original RAMPS was a shield for Arduino. That evolved over time into integrated all-in-one boards but the architecture remained pretty much the same.Quote from: beanflying on January 06, 2019, 10:49:14 pmMarlin itself is not much of an issue, I believe there are some forks/variants for STM32 chips and others. It is more the RAMPs/driver part of the equation which sucks if you try to reuse a common 3D printer board with a CNC machine.Quote from: beanflying on January 06, 2019, 10:49:14 pmAgain, it was you talking about RAMPS and those are almost all designed around this. If you didn't mean that, then sorry but I don't read minds yet.BTW, "Stepstick" is not Chinese, that's Pololu 's invention - a small DIP carrier board with an Allegro A4988 stepper driver (or similar - e.g. the Trinamic ones are popular) that gets inserted into female headers on the main board. When talking about "Stepstick" it is more about this form factor than anything else today. The idea behind this was to make the drivers easy to replace because the early designs they were failing regularly due to various overloading and short circuits on poorly built RepRaps (where this design comes from - RAMPS stands for "RepRap Arduino Mega Pololu Shield")And even if the board doesn't use these "plug-in" driver boards, they often use the same stepper driver chips directly on the PCB. Either way they would be very underpowered/lacking cooling for a CNC machine.OTOH, if you want to upgrade a router such as 3020, it shouldn't be too hard to interface a board running Marlin with the original electronics if it is serviceable (some are reasonably built but there are also some very poor ones around). It would need only a custom cable, removing the stepper drivers from the Marlin board (if it has any) and maybe some minor code modifications - the control interface for the "Stepstick" style stepper drivers is very similar (if not identical) to what these cheap routers use (a direction signal and a pulse for each step). That would be, IMO, better than trying to rip the old electronics out and trying to use a 3D printer board there instead.

author: Kilrah
author_rank: Unknown
timestamp: January 07, 2019, 01:07:09 pm
content: Quote from: janoc on January 07, 2019, 11:11:02 amIndeed. But while Marlin could totally serve as "g-code execution machine" on a router, for most uses you need manual controls a lot and that's all missing in it. There is a whole bunch of dev work to do to integrate jogging, offsets etc as well as everything you need a router's panel for into the UI...

author: janoc
author_rank: Super Contributor
timestamp: January 07, 2019, 04:44:46 pm
content: Quote from: Kilrah on January 07, 2019, 01:07:09 pmThat's true. I believe Marlin has some support for basic LCD/encoder based UI but that's good only for homing the machine and launching the job, not much else.I don't think it even supports stuff like work/tool offsets at all - there is nothing like it on 3D printers (there is no "work" or tool offset to speak of, you only carefully calibrate the Z axis offset and level the bed), so it would surprise me if it did. Also Marlin's G-code is a variant that is tailored for 3D printers, so it has 3D printing specific features but will likely miss features needed for a milling machine.GRBL is better option for a CNC mill in this regard:https://github.com/grbl/grblIt still doesn't have UI but at least it supports the necessary settings and the UI can be added.

author: Kilrah
author_rank: Unknown
timestamp: January 07, 2019, 10:04:37 pm
content: Marlin actually has quite a few things not related to 3D printers... it handles a spindle with adjustable speed, direction etc, laser heads,... so it could actually already include most of what's needed on the G-code side. I've gone through it relatively quickly a few months ago when I bought a cheap laser head, and successfully reconfigured and recompiled my printer's Marlin to use it, was basically not much more than uncommenting a few #defines to enable the features and find/map a suitable spare pin.Yeah there's a "move axis" feature in the UI but it's extremely clumsy, even for a 3D printer it's a pain, thankfully you rarely need it.

author: beanflying
author_rank: Super Contributor
timestamp: January 08, 2019, 12:37:17 am
content: There is some Marlin specific deviation to what might be considered 'Normal' GCode not a deal breaker by any means and I haven't tried to go through the list but it does existhttps://reprap.org/wiki/G-codeMove axis is a PITA on my Ender Pro's as I haven't played with the firmware to include a bed leveling routine YET. No intentions to put a sensor on it either. Changing that to respond to some sort of thumb controller in X & Y would be fairly straight forward. Z move on a secondary of some sort.Start Stop for tool changing exists in some form and moving the head to accomplish that must exist looking at the E3D changer some time back. I have never looked at tool offsets shouldn't they be handled in processing before the job starts?If forking Marlin or writing a GRBL UI from the ground up is the better option you would need to research thoroughly before starting.

author: IconicPCB
author_rank: Super Contributor
timestamp: January 08, 2019, 12:52:02 am
content: That is no more than an hours job on a decent milling machine.Please post Your G code file for a better estimate of time.The largest single panel I have machined is a full size 470 x580 panel with at least a dozen different designs on it.

author: janoc
author_rank: Super Contributor
timestamp: January 08, 2019, 05:28:47 pm
content: Quote from: beanflying on January 08, 2019, 12:37:17 amErm, nope. The machine operator isn't going to run the job back to the CAM guy to reprocess the file for each of his or her machines only because the tools are worn out differently on them. Furthermore, you need to update this frequently if you want to keep producing parts that are correctly sized (tools are wearing out continuously).You measure the tools (some machines can do it themselves, on others you have to remove the tool and measure it externally) and enter the measured lengths/diameters/whatever into the controller so that it can compensate when the code tells it to perform a certain move.The same story for probing/locating the work in the workspace of the machine. When milling PCBs it is not that big deal (just set the origin somewhere so that the board fits on your blank by jogging the cutter to touch the surface) but when you are actually milling slots or drilling holes into an existing piece, it matters - having this set wrong will make the machine drill/mill in wrong places or, in the worst case, crash the tool into the work or chassis, trashing both the work, tool and possibly messing the machine up as well.