CNC Plasma Table Motor/Electronics/Interface parts, in 2020? ........ - Page 1
Forum section: electronics / general

author: Smokey
author_rank: Super Contributor
timestamp: September 04, 2020, 03:29:41 am
content: I'm building a small cnc plasma table of my own design (about 24in x 24in work area) . The mechanical aspects are mostly finished, and now I need to select the motors, drives, and interface components and integrate those into the system. I only need 3 axis now, but I may want to add another 2 axis at some point.Since this is a plasma table, not a router, there is essentially no cutting force so the motors don't need to be nearly as big. I'm looking to go as inexpensive as reasonable since this is for my personal garage use, not a 24-7 business type use. I'm totally willing to do my own integration, but I don't want to reinvent anything I don't need to. Given the maturity of the tech and widespread use of similar components in lots of systems, there should be lots of good options now that may not have existed at a reasonable price before.What do you guys recommend now in 2020?What have you used?Any luck with cheap import ebay stuff?Does it make sense to look for a cnc machine stepper package or part out the motors, drives, and interface separately?Thanks!

author: Smokey
author_rank: Super Contributor
timestamp: September 04, 2020, 05:21:24 am
content: I also need a Torch Height Controller. I have a Hypertherm Powermax30 that has no THC support at the moment, so I would need a universal controller. If I had to I could upgrade but that would suck.

author: rvalente
author_rank: Frequent Contributor
timestamp: September 08, 2020, 02:57:51 pm
content: IN the DIY field you've pretty much all possibilities, there is also the good and the better.First things firsts, what would be your CNC controller? Mach3/4?These usually runs with controller boards, usually ethernet is better (smoothie board) + stepper drivers, I would say for you the cheap toshibas based are just fine.Recently, ethercat has been leading the way, check leadshine drivers, there is no interface board, just a daisy chain ethernet cable.As for the torch height, sorry, never made a plasma cutter before

author: Smokey
author_rank: Super Contributor
timestamp: September 09, 2020, 12:44:19 am
content: Getting ready to post a dump of the research and options I've been finding for stepper kits for plasma tables.I've been in automation for a while now, and if I was going high end build for a real production type machine I would totally put together a brushless servo system and I agree that especially for something like this, EtherCat would be really nice. Problem with that option is the cost vs performance. I feel like, especially with a plasma table, the motion requirements are so low that the advantages of a servo over stepper are really small and the size of the machine and number of axis I'm talking about won't make quite the rats nest of wiring that makes Ethercat really attractive.I have this conversation with one of my friends periodically. When he wants a new piece of equipment he just goes and buys the low end pro gear and gets working, but I spend a considerable amount of time getting to the bottom of all the options to find the most cost effective solution even if that means making large parts of it and spending more time getting it working. I try to justify it by saying I'm learning more along the way, but he's probably the smarter one in the end.

author: Smokey
author_rank: Super Contributor
timestamp: September 09, 2020, 01:56:55 am
content: Kits with motors and drivers:They are not all equivalent. The motors are different and some have components the others don't, like controllers and interfaces and more axis. This is more of an overview of options than a direct comparison.I also haven't used any of this stuff yet, so I can't attest to the quality or functionality.From Higher to Lower Cost:1) CandCNC BladeRunner Dragon Cut 300-4 (Bundle) =https://www.candcnc.net/store-home/bladerunner-dragon-cut-300-4-bundle/$2,525.002) CNCRouterParts 4-Drive DIY NEMA 23 Electronics Kit =https://www.cncrouterparts.com/4-drive-diy-nema-23-electronics-kit-p-75.html$765.003) Probotix 3-Axis Monster Hybrid Stepper Motor Driver Kit =https://www.probotix.com/CNC-CONTROL-SYSTEMS/CNC-CONTROLLER/3-Axis-Monster-Hybrid-Stepper-Motor-Driver-Kit$499.954) BuildYourOwnCNC 3 Axis Electronics Combo =https://buildyourcnc.com/item/electronicsAndMotors-3axis-425-elcombo$390.005) HobbyCNC HobbyCNC Combo Kit =https://hobbycnc.com/product/combo-kit/$3106) OMC-StepperOnline 3 Axis CNC Router Kit 3.0Nm(425oz.in) Nema 23 Stepper Motor & Driver =https://www.omc-stepperonline.com/3-axis-cnc-kit/3-axis-cnc-router-kit-30nm425ozin-nema-23-stepper-motor-and-driver-3-dm542t-23hs45.html?mfp=16o-ship-from%5B59%5D$188.42

author: Smokey
author_rank: Super Contributor
timestamp: September 09, 2020, 01:58:25 am
content: Controllers and Interface Cards:1) GeckoDrive G540 4-Axis Digital Step Drive (Drives + Parallel Interface)$2692) Warp9 Ethernet SmoothStepper (ESS) Controller =https://warp9td.com/index.php/products$1803) CNCdrive UC400ETH ethernet motion controller =https://www.cncdrive.com/UC400ETH.html$1304) CNCdrive UC100 USB motion controller =http://cncdrive.com/UC100.html$955)  Parallel Port 5 Axis CNC Breakout Board Interface =https://www.omc-stepperonline.com/5-axis-cnc-breakout-board-interface-mach3-cnc-router-kit-st-v2.html$10

author: Smokey
author_rank: Super Contributor
timestamp: September 09, 2020, 01:59:19 am
content: Torch Height Controllers:1) Built into CandCNC full system. See Above in Kits.$2525+2) TMC3in1 + SmoothStepper ESS =https://warp9td.com/index.php/faq/faq-mach4#HeightControlTMC3in1ESS + TMC3in1 = $180 + $399 = $5793) NeutonCNC THC =https://neuroncnc.com/products/003$4694) Proma THCSD Up/Down =https://www.eagleplasma.com/proma-thc-sd.html$350...CandCNC Universal Plasma Connection Kit (For machine without CNC port) =https://www.candcnc.net/store-home/universal-plasma-connection-kit/$142

author: 0db
author_rank: Frequent Contributor
timestamp: September 09, 2020, 08:34:52 am
content: According toLinuxCNC, the parallel port is the bestBut readhereQuoteQuote

author: 0db
author_rank: Frequent Contributor
timestamp: September 09, 2020, 02:30:58 pm
content: Quote from: Smokey on September 09, 2020, 01:58:25 amis there any schematic that internally describes this board?

author: Smokey
author_rank: Super Contributor
timestamp: September 09, 2020, 11:24:21 pm
content: This is a different board without the relay, but I think it's essentially the same otherwise. Just some optos and a power supply.https://www.electronics-lab.com/project/parallel-port-breakout-board-with-buffer-for-cnc-routers/

author: rstofer
author_rank: Super Contributor
timestamp: September 22, 2020, 07:49:42 pm
content: Don't forget to include the mass of the product when figuring the required motor torque. I would be cautious about small motors. Look around and see what the commercial equivalents are using.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 24, 2020, 11:30:56 pm
content: I've bought around 6 Nema23 motors with drivers and 2 Nema34 motors with drivers from Ali, and they all work.The "closed loop steppers" are significantly quieter in operation, and well worth the price difference.In the bigger CO2 lasers there is often a small timing belt on the motor to an intermediate axle, and then a cut open timing belt to move the gantry, and it usually adds a extra gear reducion of 1:3. These intermediate axles can be bought as spare parts for reasonable prices. I'm not sure if plastic or rubber timing belts are the best option for a plasma cutter. You may want to consider a regular bycicle chain, but don't make the sprockets too small, or you will get into trouble because those sprockets are polygons (with each teeth) and not "circles".It's probably a good idea to use these.Stepper motors loose torque at High RPM, (This gets serious above 600RPM, depending on power supply voltage) but with the 1:3 reduction you need less torque from the motor. Result is higher resolution, and more freedom in choosing the diameter of the pulley's.If you want to go LinuxCNC. I guggest to add a MESA FPGA card. I think they cost around EUR150, but the extra reliability is probably well worth it.If you want to go cheap...I've burned a Grbl clone for an STM32 into a "Blue Pill" and added some good old 74LS line driver chips to drive the opto couplers in the stepper motor drivers. Soldered it all on Matrix board.I use bCNC for driving Grbl. It's a simple program (for today's standards) but it does get the job done, and it has some nice features for post processing your CAD files. It can add stuff as tool offsets, lead in and out.It also has special features for cutting plotters, which add "swirls" in tight corners.I do not know of special features for plasma cutters in bCNC. Would any be needed?bCNC is also written in Python, and there are some 20+ plugins such as spirograph generators, puzzle pieces and such. You can study those to write your own plugins for special functions if needed.bCNC also has a Z-height "probe" function built in.Original function for this is for PCB milling, to take of the copper, and leave the glass alone, but the same feature can also be used for your probe height compensation of course.

author: beanflying
author_rank: Super Contributor
timestamp: February 23, 2023, 07:35:47 am
content: Bit of a necro post but interested if you got your table finished @Smokey?I picked up a cheap and virtually unused Chinese 6090 router a few months ago and I brought a 45Amp Plasma around a year ago and a new compressor to go with it 6 months earlier (preemptive purchase).I have done a fair bit of looking around at options for making al the bits fit together for a small table but likely when space allows a larger 1/2 sheet one. THC is a bit of a must and Proma offer a few standalone options or the all in one version I opted for as I am currently fairly time poor to want to fuss around with a more ad hock system.Tried the software out that is available with it and no fuss if that is all you want and with a generic Plasma post processor it looks like it will work fine with code produced out of Fusion 360 (simulation mode worked fine) or just with dxf's generated by it or any other CAD package then using the built in CAM part of it.Part of the benifit of this system is you can feed it (non HF) raw arc voltage and the interface has really good separation back to the controller and PC. Cracked it open and yep 2-3kV without doing any numbers.Manual and software herehttps://proma-elektronika.com/and there is some ok videos on YouTube from him and others on it as a solution and also farcebooksupport groups.Ordered the steel for the water table so things being well a month or two until I make some cuts.

author: coppercone2
author_rank: Super Contributor
timestamp: February 25, 2023, 12:47:50 am
content: I thought AVE was working on this a while back?

author: Smokey
author_rank: Super Contributor
timestamp: February 25, 2023, 07:04:11 am
content: Quote from: beanflying on February 23, 2023, 07:35:47 amLike so many things, this one got put on hold for something more important. Then I changed the design. Then I put that design on hold for something more importantSome day.

author: coppercone2
author_rank: Super Contributor
timestamp: February 25, 2023, 07:16:00 pm
content: I need to refill O2 and N2 tank to see if I can hook up my gas mixer to the plasma cutter to get nicer cuts with a slightly tuned gas mixture

author: beanflying
author_rank: Super Contributor
timestamp: March 03, 2023, 04:28:14 am
content: Quote from: Smokey on February 25, 2023, 07:04:11 amA little Inspiration to keep on going with yours.I will make a new thread for the whole project but this is a small step to tick off.My Dumb Cigweld (Esab in Oz) 45A Plasma is going RS485 smart. Proma also make separate THC modules and Isolated Voltage dividers but this all in one makes fitting it inside the box easy. All the switching bits are on the other side of an Aluminium sheet and as it is a non HF Plasma this should work out well rather than doing the same horrible things I have seen others wire up and use double sided tape or cable ties strapped outside the Plasma or wood screwed onto a wall ....

author: nctnico
author_rank: Super Contributor
timestamp: March 06, 2023, 11:59:08 am
content: While you are at it, replace the small pressure regulator with a bigger one. Those small regulators have a large pressure drop and are quite inaccurate. I retrofitted an AW3000-02 (from Aliexpress) regulator on my plasma cutter to get a more even pressure. The original one dropped nearly 1 bar while cutting.