Hey all, Thank you so much for coming by and watching this evergreen video. Please check out how I am rethinking BuildYourcnc.com and PLEASE let me know what you would like to see on that platform. If you are in the market for CNC, 3D printer, Laser components, give it a try. This is the best way to support me and my channel. Wow!! I can't believe how many awesome comments I got from this video. I am thinking of making a series for this shielding subject. To summarize the comments so far: - Shielding Methods: Various shielding techniques including using ferrite cores, and metal enclosures with proper grounding. I will add inductors to this so as to reduce higher frequency noise which we saw in the video. - EMI Sources: AC devices (like spindles and air compressors) tend to cause more EMI than DC devices. VFDs and plasma cutters are also mentioned as significant noise makers. - Voltage Considerations: choosing 24V over 5V for their CNC system due to EMI concerns. - Testing Methods: keep ground connections very short when measuring EMI to avoid creating a "magnetic antenna" effect. Don't double with motor wire on itself to limit possible cancelation of the noise. - Wire Configuration: folding test wires can reduce induction. - Video Feedback: showing worst-case scenarios early on and editing for a more natural conversational flow.
@@TouChA0 Time to grab some coffee and take a watch! Haha. just tuning in right now. Thanks for the heads up. I like when others do reaction videos as this is a great way to learn from others.
@@TouChA0 Funny, I just put a long comment on his video to touch on specific points, but it is not there. The main idea of my comment was in appreciation of his reaction and how I can learn from it. Not sure if he removed it, or it was flagged. Here is the comment I made (I saved it because I knew he may want to remove it, which, if he did, it's kind of low in my opinion) so you can understand my stance: Hey Corvetteguy50... Thanks for making this reaction video. I hope you watch some of the other videos I have on my channel. I think you will get to know me better. It's hard to get a good understanding of me from one video, but I love the information you provided and I can learn form it. I am grateful for the information. This is partly how I learn. Funny, this reminds me a a desk crit in my college days. By the way, I do use PayPal as my payment gateway. [2:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) this is my first test. In my pinned comment, you will see that I will be doing further tests including a spindle/VFD, and in a CNC setup. [6:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Good to know. I will be doing more research on this. Although I haven't seen any issues with using an USB controller for 13 years of my 17 year of my CNC journey, I will delve deeper into this. [9:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yep, I'll be doing that test. [11:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Don't have an EFM reader, but intrigued. I brought that up because I talk to many customers daily on troubleshooting issues and they don't have the expertise to know you "can't" us a multimeter. [12:43](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) I believe it does make sense, if you are troushooting as a business, or you have a CNC that is required for on-time production. (I commented! Haha). Why not market this tool? [13:45](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) I saw this on job sites where the CNC needed troubleshooting. Your comment is great and taken to heart. [15:27](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Good to know. As an aside, these terminals are rated for a much larger gauge. That b being said, I always use wire ferrules. I did speak about ferrules and not using them for this test. You skipped that section of the video. [19:12](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) That's not accurate: I experienced horrible EMI using a parallel port system back in 2007-2008 regularly is the signal wires were too close to the stepper motor wires. At that time, I had very little knowledge of shielding. [21:01](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) what is wrong with using an affiliate link? I am providing options for the buyer and selling the ones in my shop at a higher price with free technical support. If this is a perceived problem, I would like to know so I stop doing it. [22:32](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yes, you are correct, a very critical point which is pinned at the top of my comments on this video comment section. [23:35](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yes, wrong choice of words. I have a hard enough time thinking about what to say, but you are right. I am going through some pains, but that is kicking me in the butt to try to improve my website. This is just a sponsor section where I am sponsoring myself (or at least trying to). I stated in this section that I am providing curated content, items that I have experience with and know the quality. By the way, PayPal is my main gateway system for payment. The credit cards image is there to show I do accept them and at the time I put them there, PayPal was young and not trusted. [27:50](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yeah, I'm not the best at conveying my message and I need to learn the right way. [32:49](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) I remember Dave Jones talking about this way back, but I remember him saying the DC- does eventually go to earth ground, but if I am mistaken, I will mention this in my next video. However, DC- can be used for shielding, but I know it is not best practice. I will mention this, but I do mention this in a previous video where I put together a larger set of CNC electronics. Again, thank you so much for the feedback. It is ALL taken to heart.
Thank you for posting this video! I came here from some other guy's video that strangely TH-cam decided to recommend to me. After listening to his incoherent ramblings for FAR too long I put his channel on my Do Not Recommend list and found your channel. I design avionics for aircraft and spacecraft and we have to consider very similar issues that can affect sensors and actuators in those environments. Thank you for taking the time to put together an example with a scope to show some of the effects of interference. You've earned another subscriber. Please continue to post more of these types of videos.
Thank you so much!! I have a lot more investigating to do with EMI and how shielding can help. Regarding the "other guy", I never say that I know anything, and he professes to know everything. I am helped by my awesome commenters like you and everyone else that guides me and inspires me. I will never stop learning! I can't wait to continue these tests and seek more noise and seek how to eliminate it.
Okay, so I just finished watching this video. I have (3) CNCs, two of which I've built myself; one has been "employed" for a year now, while its clone is still in construction phase electrically speaking. Am building the panel for it now. And am wanting to ensure there is little to no EMI leakage, which is something that has plagued the #1 build from time to time. There doesn't seem to be a pattern, or reason for the processor to "forget" or ignore commands to start or stop an operation. From the onset, I insisted on using shielded cable for my limit switches. Though the stepper cabling provided from a supplier was not shielded. I asked a friend that has a Tormach how important to have such? But he was opinioned it was not. Yet, I'm convinced that yes, it is so! Therefore, on this 2nd clone build, all cabling is going to be shielded! Thanks for your advice. I shall use it wisely!
Commenting from my mobile, not sure if someone else has noted this, when you run the motor wires in your long loom, you are saving space by doubling the wires back in the same place, so the generated interference is being cancelled out by the return wire. To get a good concept of noise, run a pair of wires from the limit switch along the motor wires , And monitor the limit switch signals with your scope. You will get some nice noise while the motors are running and reversing direction. But for REAL noise hook up a vfd and spindle! Thanks for the content and videos, you have been a constant source of information for my own CNC buolds
Thanks for the commment, and I have a pinned comment with a summary of the comment and future test. Yes, this is a new comment regarding cancellation, but the VFD, plasma, and laser video is coming. I'm not sure if there would be a cancellation as this phenomenon would solve a lot of problems, but a test would be fun to do.
Super cool - watching now. I still have my original BuildYourCNC that I built from your plans like 16 years ago out of MDF. Going to utilize the steppers from it for a plasma CNC that I'm building. This will be very important. BTW I love the Siglent scope. - John
Wow. So cool!! Remember to separately ground your plasma torch. Hypertherm has great documentation on this. Let's see how long the equipment from way back lasts!! Keep my posted!!
From experience you always ground and use shielded cable leeds. But i have more of an issue with the specific controller card. The same card at least in the latest versions its not capable of serving synchronous movements so i would advise anyone to not cheap out on the controller card. It will save you the hours of diagnosis on why the machine doesn't move properly. This is especially bad for gantry machines where they can easily bind up and eat your leed screws for lunch. I have seen this happen way to many times to be comfortable with recommending this kind of controller card.
Great video! You covered somethings I wonder about. I have started my CNC mill build and have the controller cabinet done with everything mounted and connected. I was thinking about how to minimize any possibility of EMI coming up when I get ready to test. I did choose to set up my system (Acorn cnc) to run on 24v instead of 5v due to the concern of EMI now I wonder if that was necessary.... I shielded everything that I could except for the lengths of wires that had to have enough length to be connected to where they needed to go and grounded the shield wires.
Thanks!! Check out some of the amazing feedback in the comments. I will be doing a followup video (maybe a series) on bigger EMI offenders. At minimum, shield and potentially use ferrite beads or coils to create even better shielding.
Great video. On my first cnc I solved all of my interference issues by just removing the spindle wire from the loom and running it on its own. The VFD creates massive interference on the rest of the loom.
Excellent. I will be delving into that soon. I wan't to see if I can get the EMI eliminated in my tests so that the signal wires can still be in the same location as the other cables, like the Spindle/VFD cable.
@@PatrickHoodDaniel get a common line efi filter for the supply side to the vfd and a choke on the spindle side. Clough42 did a really good video showing how this solves all the interference issues.
@@raindeergames6104 I am currently watching that video. Thank you for the recommendation. I will be doing the VFD/Spindle tests in a future video. I may not setup the measuring method he is using (proper coil with resistor), but I will use the choke on the supply side as an added recommendation and cite his video. To measure the waveform, I will be using ABB drives instructions, but I will also be laying the signal wires in parallel to get a more "in context" EMI readings since this is what would be done in a real world scenario. Using the coiled up probe is an interesting idea though.
@@basserex4991 Not sure. I haven't used an RF meter, but the idea sounds interesting. A handheld oscilloscope could also come in handy with car audio so you can get better access to all of the components. I would also echo what @-BlackBird7 said. Grounding is a big deal as I show in the tests.
@@PatrickHoodDaniel yes i have a osciloscope. The problem is with only one Amp. Waveform is very very dirty. Noised wave ( FAT wave) But signal RCA is clear. Amp is ok because i tried other Amps and problem is too but sometimes disconect power wires from amp can help back clear sinewave but problem is back. I think its EMI, antena, xenons and more. Its not easy :/
21:34 that "stair stepping" is classic impedance mismatch between the cable and the receiver. With the limit switch closed, you essentially have a large loop, and the input on the controller is relatively high impeadance, so you end up with ringing in the cable that constructively interferes with itself as the interference from the motor leads bounces back and forth from one end of the cable to the other. If you put a resistor in series with the limit switch, that would go away. The tricky part is measuring the "characteristic impedance" of the cable - you need an LCR meter, and you need to measure the short circuit inductance and the open circuit capacitance of that cable, and then you can calculate the characteristic impedance, and terminate the cable with the correct resistor. Of course if you shield the cable, the noise induced from the motor wires never makes it in to the cable in the first place, so it's not going to ring like that, but terminating the cable properly will also lead to cleaner signals to the controller when the limit switch closes as well
Excellent comment!! Thanks!! I would have through a ringing would look more like a springing that acts like a transient response. Thank you for this education. I want to try the resistor in series on the next test. Without the use of a LCR meter, is there another way to test? Can I use the frequency of the stair step by measuring the period to determine needed values?
@@PatrickHoodDaniel Without an LCR meter, the only way is to use a fast edge generator, and a resistance substitution box (or a potentiometer), and try various values until the ringing goes away. To see an explanation of what's really happening, see a couple of videos by w2aew - "#37 use a scope to measure the length and impedance of coax", and "#88 cheap and simple TDR using an oscilloscope and 74ac14 schmitt trigger inverter". It doesn't matter that he's talking about coax, and you have plain wires - it's the same concept. Terminating the "bus" of high speed digital signals (at both ends) is also important to prevent ringing as well - an unterminated high speed digital line will destroy the signal integrity easily. Some of your explanations of what's really going on here are a bit shakey, but EMI interference is a complicated topic, and most EE's don't have good explanations either, unless they've specifically researched and looked into it (probably because they've run into signal integrity issues) as well. It's not a subject that's taught in typical undergrad curriculums, though it really should be, as CPUs and even micro controllers get faster and faster, it's very easy to run into problems.
@@PatrickHoodDaniel You could also try using a twisted pair for the limit switch - both shielded and unshielded. Just cut apart some ethernet patch cables for unshielded twisted pair. Ethernet twisted pair should have a characteristic impedance around 120 ohms, so you shouldn't need to measure it.
@@gorak9000 I like the idea of using a pot to ring out the ringing! Haha. I love these types of experiments. This is how I learn. I will make sure to watch those videos before the next tests. I'm sure this may merge into my uC videos some day. Loving your comments. Thank you so much!
2:18 Those have 2 channels! The third BNC is a external trigger input. If you are not used to work with oscilloscopes I would strongly advise getting a portable or USB scope that has individual isolated channels because it's very easy to short things and blow up something if you are not careful (especially with bench scopes since all channels are grounded and earthed). PS : NEVER try to measure mains voltage with a scope unless you REALLY know what you are doing.
Thanks. Will do. Part of the way I learn is by creating videos on the subject. I do not have many hours on an oscilloscope, so the comment is greatly appreciated. I want to get to know my PoScope a little better, so I will use that on the next tests.
I want to add that as per your comment, I am seeking more education on measuring 3-phase output for the VFD I will be testing soon. Even though I didn't talk about testing AC anything in this video, and not even elude to doing so, your comment came at the right time before I decide to test AC with my oscilloscope. Although, this scope had gotten a lot of use over the years and wouldn't have concerned me if it did fail due to my ignorance. It would have just caused me to get a better one, and do more research. Life is a great teacher.
Keith in the UK has written a book and he says that he has issues with wires going to end stops that aren't shielded causing issues . Keith has a TH-cam channel where he builds and flies RC planes using a CNC foam cutter. Thanks for the video
Thank you kindly for watching. That is probably due to the older 5V limit switch connections. I remember where the older parallel breakout boards used a few of the parallel pins to serve as inputs. Even with some conditioning, those signals are relatively weak. I remember many customers back around 2007-2014 or so needing to make modifications to avoid this. Shielding is definitely the way to go as an overall solid system. Additionally, my explanation at 24:09 may be one of the issues many had because the signal wire had no path to ground depending on the NO/NC configuration.
Not absolutely, but it is best practice. I show this more specifically on this video: th-cam.com/video/5kHnuWQ2lr0/w-d-xo.html at timestamp 28:23. You can use the DC- to ground the shielding only if there is not other option. You should always shield to the body of the CNC enclosure.
Generally, DC doesn't create a huge amount of EMI. AC does as it generally has higher voltage (220v-240v) and frequencies (50-60hz) and this is what really causes noise, especially switching things on and off, which causes EMI spikes - the data lines act as an antenna, picking up those signals and causing step interruption. Two sources I've found that really cause issues are AC spindles (my Kress brushed spindle is a nightmare) and my air compressor which uses an AC motor can flood the workshop with EMI. AC motors work by energising phases, effectively switching them on and off really fast and that is the source of the noise (think "switching" PSU - the clue is in the name)
Whether in DC or AC systems, the process of switching-turning current on and off-creates sharp transitions in current and voltage. These transitions generate high-frequency components, which can radiate as EMI. The rapid switching creates harmonics that can extend into the radio frequency (RF) range, leading to interference in nearby electronic devices. People often confuse pulsed DC with AC because both can generate EMI, especially when switching is involved. However, they are fundamentally different. AC naturally alternates, while pulsed DC involves periods of on and off states, leading to distinct types of interference. It's the switching in both AC and DC systems that is often the root cause of EMI, not the mere presence of AC. This is why devices like switching power supplies, regardless of whether they are rectifying AC to DC or working within a DC system, are significant sources of EMI. In a SMPS (switch mode power supply) it is not the AC part that creates EMI but the DC part where the switching occurs. Those are actually DC-DC converters since the AC is directly converted to DC and the voltage "conversion" happens in the DC part. This is also why they can work with DC input because they are actually a DC converters.
@@ppdan This is a really good comment and why I don't see the interference from AC cords. In my tests, I am trying to imitate where cables and wires would be placed in a typical CNC setup. The wires and cables may not come close to the actual devices like switch mode power supplies, but I can test these circumstances. What do you think?
My limit switches kept triggering from router noise. I put capacitors near the switch to hold a charge (with resistor at micro controller to charge). Never had a problem since!
@@TheRainHarvester Sure. Where in the world are you located? I use and offer CAMBAM because I know the developer (met him in the Austin MakerFaire in 2007). I am very interested in talking about software with people that care about the software.
@@TheRainHarvester I just watched your video on GatorCAM. I also looked at the price! Why such a low price? Is this an introductory price until you have more features worked in?The V-bit lettering is a feature that is quite impressive and might be the only reason folks purchase v-carve, which is very expensive.
@@PatrickHoodDaniel I'm in central Texas. I'd like to talk to you! I've followed you since all your color-animal cnc inventions (since 2014?)!! Maybe i should go up in price. But upgrades will be free for anyone getting in early. I've got BIG plans for v-bit carving I think even the other expensive packages don't support! I really do not like RENTAL software!!
Just watched corvette's video, that is 18 minutes i will never get back (twice speed), also read your looooong reply, i did not bother to comment on it at all as talking from a couch is useless, he should make a video but i sincerely doubt it. Your reply was very civilized, despite him not being much. Regards.
Oh my god, why didn't I watch it at that speed!! Yeah, the couch thing... Ugh! I'm sorry you lost your time, butt I hope you were able to get some enjoyment out of my very long chit-chat.
@PatrickHoodDaniel thank you for your time to reply to all this, much appreciated, and for helping others. I try to help people building cnc machines daily on the forum, where i find it quite difficult to properly explain shielding and grounding, and since you did a good job, i will gladly point them your way. Again, thank you very much. P.S. i have build logs of all my machines on the linuxcnc forum look for tommylight
A cross-hatch weave of all your wires around a core of 1/2 inch cotton rope will help mitigate any antenna effects, and is often used in high-end audiophile grade speaker cable for eliminating RFI signal noise. A second option would be to use a shielded coaxial cable, depending on how powerful the background EMI radiation environment is. And the third option for extreme measures is to not use copper wire at all and instead use fiber optical links, which except for the emitter and receiver are basically immune to EMI interference. That would be like in a case where your machine was operating in close proximity to a high voltage em field such as a high voltage transformer or Tesla coil.
Sounds like the building of an inductor with some extra twisting. Sound like a solid plan. The fiber optic opinion I sell with my plasma THC controllers. Those are definitely a good idea. Thanks for the suggestions!
@@BrentLeVasseur buildyourcnc.com/item/electronicsAndMotors-electronic-component-plasma-thc-plasmaControllerAndSensor and buildyourcnc.com/item/electronicsAndMotors-electronic-component-plasma-thc-plasmasens-Sensor
@@PatrickHoodDaniel If only I had a workshop where I could put that stuff, I’d love to get a CNC machine and plasma cutter. Unfortunately I live in a small two bedroom apartment.
Others have already suggested this but if you want a useful scenario you really do need to redo these tests with the spindle motor wires instead of the axis control control wires. The induced current from the spindle would be much greater.
Thanks for the comment and yes, I put this in my pinned comment for what needs to be put into the next video. I may make a series because different CNC technologies (Plasma, Laser, Spindle based, Router based, etc) has interferences from disparate sources and each deserves their own video.
I use ferite cores on my data lines and also have a metal enclosure with a dedicated ground which goes via an earth wire to a ground spike outside my workshop. All components in the enclosure have a connection to the ground bolt in a star configuration (dont hook up in series as you will get a ground loop!)
Thanks!! I briefly talked about the enclosure aspect at the end of the video. It is important. I will make a followup video on other aspect, including the enclosure, but I will also include the sue of ferite cores and coils for induction to reduce the higher frequency noise.
Are data lines really a big problem since they mostly don't run for big distances along motor lines? Limit switches can be a real pain because those run along lots of stuff that can create interference. To be honest, the only CNC I ever owned is a small table version that I used to make PCBs and the problem I encountered was that switching the DC spindle would "trip" limit switches.
@@ppdan No, data (or pulse) lines are not a big problem as that is why I didn't do those tests. However, the closed loop motors have encoder cables. These are always shielded and I have never seen them with ferrite cores, but that doe snot mean that they would not benefit from ferrite cores.
Hi Patrick. Clinton here from South Africa. Hope you keeping safe during the storm. I have a quick question. I'm running Mach3, with a Mach3 usb controller card (the red one) do you have any videos on connecting a router or plasma cutter to this card (switching and pin allocation) did a quick browse and didn't seem to find anything. If so, could you please link the video? Thanks. And keep safe. Keep up the great work.
I do, but the video is in the members area. I have been moving some of the videos to the members area to benefit the paying members. However, I am happy to talk about it in a livestream on the Tuesdays and Thursdays that I focus on CNC stuff (1:00 pm Eastern). Hope to see you there.
My input- you looped the conductors for the motor back over themselves. That causes a lot of cancelation in the induced field to the adjacent signal wires. And yeah- a brushed spindle motor will make a much messier signal than the steppers because of the higher current and possibly higher dv/dt
Yeah, I got the same comments from others. I need to retest for those conditions. I will be testing with a spindle, but I wasn't planning on testing with brushed routers. There are still a lot of CNC router enthusiasts using routers, so maybe I should. It would make for some worst case scenarios. Thanks for the comment!
@@PatrickHoodDaniel thanks for the reply! Make sure it’s a brushed spindle (like I have on my desktop machine) because the commutator makes for very high dv/dt when it switches polarity!
hi i used this controller for my cnc. machine runs smooth but sometimes machine pauses, in the middle of g code running, for a second and resumes again without any warning or indication and randomly repeats that. sometimes it pauses and moves in wrong direction damaging the job and tool. i coudnt figure out the actual fault. i udes shielded wires too.
Not sure what the problem could be. The fact that it ran in the opposite direction tells me that the direction signal wire may have gotten interference, or is a loose connection. The direction signal is either high or low. If it was high, then the connection broke, it would go low (depending on how it is wires and if it is active high or active low.
I think you will find the "interference" at the millivolt levels is actually much lower than you saw. The reason is your ground clip and the wire it is connected is a HUGE magnetic antenna. Keep your ground ULTRA SHORT, using a ground clip on your probe, ...ditch the ground wire for these type of measurements!
@@stevenbliss989 thank you kindly for the comment. An incorrect ground probe setup doesn't explain the moments where I measure absolutely no interference. The same ground connection was used.
@@PatrickHoodDaniel You are right but he does have point. Always probe ground and tip as close as possible. Also, while a normal x1 probe has no problem measuring signals up to 15-20MHz and your scope only has a 25MHz bandwidth (which is more than enough for what you are doing there), personally I use a x10 probe (or switchable probe switched to x10) to have less capacitive load introduced by the probe. But this is me and using a x1 probe for what you are doing there is perfectly fine. Just keep that in mind if you ever measure things at higher frequencies (especially square waves), a x1 probe has limited bandwidth. PS : I have seen cheap x1 probes that would already struggle with 5MHz making square waves look like crap.
Just came across your stream, very interesting. I am not sure of the reason of folding the test wires. I believe by doing so reduces induction along the wire’s length. Try testing without the single fold. The current flowing produces a field that is opposite the return wire, producing a zero field. We used to make bifilar coils that were effectively just resistors.
Personally I think you would likely have a larger issue by testing the wires running next to the router or spindal wires. I believe that the noise of a brush 120v motor and a VFD spindal would cause a much greater issue on the wires, especially the switch wires.
I had a couple of issues when I had a brushed router motor on mine in the beginning. I ended up buying tome ferrite snap ons and snapping them on the router power cables, and it resolved the issue. I have a feeling that the Z axis which has all of the wires running to it is the most susceptible. The Z axis has a router, a stepper motor and a limit switch. All wires run to that. And the router power being parallel to those other wires I think is the most likely source of many CNC issues. Shielded wires to the Z axis is definitely the best option to eliminate those issues. Buy sometimes those ferrite snap ons can help in a pinch. Just my 2 cents
Hi nice video! It would be interesting if you hooked up a plasma cutter or a vfd and did the same tests. Those are the two biggest noise makers that I know of. Thanks
If I might make a suggestion, excellent and valuable video, shouldn't discount that in the beginning. Also, if you showed the worst case in the beginning, it would provide motivation to watch the rest.
you have been a great resource on matters cnc. however, id ask that you edit your videos to appear more of a natural conversation instead of snappy clips put together. meaning no offense, but it makes it a bit difficult to follow along
@@brianxavier8873 haha, I don't think you would like to see that. There's like 5 minutes between each thought. One day, when I get more accustomed to being on camera, maybe the thought patterns will stick closer together. Maybe I'll invest in a teleprompter.
For sure, but no puck-up lines is no rejection and no pick-up either. I don't have any experience in poor quality pick-up lines, but I once gave a girl a rose in a mall and that worked.
@@tomaberisha5688 Great! Thanks! I love LinuxCNC. Before I got into using Mach3, I was a totally dedicated LinuxCNC user. I also used LinuxCNC for my pick and place machine with all kinds of awesome gcode coding. Much appreciated on the share.
Hey all, Thank you so much for coming by and watching this evergreen video. Please check out how I am rethinking BuildYourcnc.com and PLEASE let me know what you would like to see on that platform. If you are in the market for CNC, 3D printer, Laser components, give it a try. This is the best way to support me and my channel.
Wow!! I can't believe how many awesome comments I got from this video. I am thinking of making a series for this shielding subject. To summarize the comments so far:
- Shielding Methods: Various shielding techniques including using ferrite cores, and metal enclosures with proper grounding. I will add inductors to this so as to reduce higher frequency noise which we saw in the video.
- EMI Sources: AC devices (like spindles and air compressors) tend to cause more EMI than DC devices. VFDs and plasma cutters are also mentioned as significant noise makers.
- Voltage Considerations: choosing 24V over 5V for their CNC system due to EMI concerns.
- Testing Methods: keep ground connections very short when measuring EMI to avoid creating a "magnetic antenna" effect. Don't double with motor wire on itself to limit possible cancelation of the noise.
- Wire Configuration: folding test wires can reduce induction.
- Video Feedback: showing worst-case scenarios early on and editing for a more natural conversational flow.
you don't see this cha nnel
cnc corvette guy 50 he is doing a reaction for this video
@@TouChA0 Time to grab some coffee and take a watch! Haha. just tuning in right now. Thanks for the heads up. I like when others do reaction videos as this is a great way to learn from others.
@@TouChA0 Just watched it in it's entirety. I like the feedback that he gave and I can definitely learn from it.
@@TouChA0 Funny, I just put a long comment on his video to touch on specific points, but it is not there. The main idea of my comment was in appreciation of his reaction and how I can learn from it. Not sure if he removed it, or it was flagged. Here is the comment I made (I saved it because I knew he may want to remove it, which, if he did, it's kind of low in my opinion) so you can understand my stance:
Hey Corvetteguy50... Thanks for making this reaction video. I hope you watch some of the other videos I have on my channel. I think you will get to know me better. It's hard to get a good understanding of me from one video, but I love the information you provided and I can learn form it. I am grateful for the information. This is partly how I learn. Funny, this reminds me a a desk crit in my college days.
By the way, I do use PayPal as my payment gateway.
[2:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) this is my first test. In my pinned comment, you will see that I will be doing further tests including a spindle/VFD, and in a CNC setup.
[6:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Good to know. I will be doing more research on this. Although I haven't seen any issues with using an USB controller for 13 years of my 17 year of my CNC journey, I will delve deeper into this.
[9:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yep, I'll be doing that test.
[11:00](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Don't have an EFM reader, but intrigued. I brought that up because I talk to many customers daily on troubleshooting issues and they don't have the expertise to know you "can't" us a multimeter.
[12:43](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) I believe it does make sense, if you are troushooting as a business, or you have a CNC that is required for on-time production. (I commented! Haha). Why not market this tool?
[13:45](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) I saw this on job sites where the CNC needed troubleshooting. Your comment is great and taken to heart.
[15:27](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Good to know. As an aside, these terminals are rated for a much larger gauge. That b being said, I always use wire ferrules. I did speak about ferrules and not using them for this test. You skipped that section of the video.
[19:12](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) That's not accurate: I experienced horrible EMI using a parallel port system back in 2007-2008 regularly is the signal wires were too close to the stepper motor wires. At that time, I had very little knowledge of shielding.
[21:01](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) what is wrong with using an affiliate link? I am providing options for the buyer and selling the ones in my shop at a higher price with free technical support. If this is a perceived problem, I would like to know so I stop doing it.
[22:32](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yes, you are correct, a very critical point which is pinned at the top of my comments on this video comment section.
[23:35](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yes, wrong choice of words. I have a hard enough time thinking about what to say, but you are right. I am going through some pains, but that is kicking me in the butt to try to improve my website. This is just a sponsor section where I am sponsoring myself (or at least trying to). I stated in this section that I am providing curated content, items that I have experience with and know the quality. By the way, PayPal is my main gateway system for payment. The credit cards image is there to show I do accept them and at the time I put them there, PayPal was young and not trusted.
[27:50](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) Yeah, I'm not the best at conveying my message and I need to learn the right way.
[32:49](th-cam.com/video/zZf4yfEVGJY/w-d-xo.html) I remember Dave Jones talking about this way back, but I remember him saying the DC- does eventually go to earth ground, but if I am mistaken, I will mention this in my next video. However, DC- can be used for shielding, but I know it is not best practice. I will mention this, but I do mention this in a previous video where I put together a larger set of CNC electronics. Again, thank you so much for the feedback. It is ALL taken to heart.
@@PatrickHoodDaniel yutube remove comment links as i had said
Thank you for posting this video! I came here from some other guy's video that strangely TH-cam decided to recommend to me. After listening to his incoherent ramblings for FAR too long I put his channel on my Do Not Recommend list and found your channel. I design avionics for aircraft and spacecraft and we have to consider very similar issues that can affect sensors and actuators in those environments. Thank you for taking the time to put together an example with a scope to show some of the effects of interference. You've earned another subscriber. Please continue to post more of these types of videos.
Thank you so much!! I have a lot more investigating to do with EMI and how shielding can help. Regarding the "other guy", I never say that I know anything, and he professes to know everything. I am helped by my awesome commenters like you and everyone else that guides me and inspires me. I will never stop learning! I can't wait to continue these tests and seek more noise and seek how to eliminate it.
Okay, so I just finished watching this video. I have (3) CNCs, two of which I've built myself; one has been "employed" for a year now, while its clone is still in construction phase electrically speaking. Am building the panel for it now. And am wanting to ensure there is little to no EMI leakage, which is something that has plagued the #1 build from time to time. There doesn't seem to be a pattern, or reason for the processor to "forget" or ignore commands to start or stop an operation. From the onset, I insisted on using shielded cable for my limit switches. Though the stepper cabling provided from a supplier was not shielded. I asked a friend that has a Tormach how important to have such? But he was opinioned it was not. Yet, I'm convinced that yes, it is so! Therefore, on this 2nd clone build, all cabling is going to be shielded! Thanks for your advice. I shall use it wisely!
Thank you for watching the video!! I agree... Absolyutely it is. I will be making more tests with bigger EMI offenders.
Commenting from my mobile, not sure if someone else has noted this, when you run the motor wires in your long loom, you are saving space by doubling the wires back in the same place, so the generated interference is being cancelled out by the return wire.
To get a good concept of noise, run a pair of wires from the limit switch along the motor wires ,
And monitor the limit switch signals with your scope.
You will get some nice noise while the motors are running and reversing direction.
But for REAL noise hook up a vfd and spindle!
Thanks for the content and videos, you have been a constant source of information for my own CNC buolds
Thanks for the commment, and I have a pinned comment with a summary of the comment and future test. Yes, this is a new comment regarding cancellation, but the VFD, plasma, and laser video is coming. I'm not sure if there would be a cancellation as this phenomenon would solve a lot of problems, but a test would be fun to do.
Yes, zig zaging back on them selves is a good way of overcoming loops.
Loops creates a inductor
Super cool - watching now. I still have my original BuildYourCNC that I built from your plans like 16 years ago out of MDF. Going to utilize the steppers from it for a plasma CNC that I'm building. This will be very important. BTW I love the Siglent scope. - John
Wow. So cool!! Remember to separately ground your plasma torch. Hypertherm has great documentation on this. Let's see how long the equipment from way back lasts!! Keep my posted!!
From experience you always ground and use shielded cable leeds. But i have more of an issue with the specific controller card. The same card at least in the latest versions its not capable of serving synchronous movements so i would advise anyone to not cheap out on the controller card. It will save you the hours of diagnosis on why the machine doesn't move properly. This is especially bad for gantry machines where they can easily bind up and eat your leed screws for lunch. I have seen this happen way to many times to be comfortable with recommending this kind of controller card.
Great video! You covered somethings I wonder about. I have started my CNC mill build and have the controller cabinet done with everything mounted and connected. I was thinking about how to minimize any possibility of EMI coming up when I get ready to test. I did choose to set up my system (Acorn cnc) to run on 24v instead of 5v due to the concern of EMI now I wonder if that was necessary.... I shielded everything that I could except for the lengths of wires that had to have enough length to be connected to where they needed to go and grounded the shield wires.
Thanks!! Check out some of the amazing feedback in the comments. I will be doing a followup video (maybe a series) on bigger EMI offenders. At minimum, shield and potentially use ferrite beads or coils to create even better shielding.
@@PatrickHoodDaniel I look forward to it!!! once I get my mill dialed in I will be doing a plasma too. Cheers!
@@-BlackBird7 Excellent!
Great video. On my first cnc I solved all of my interference issues by just removing the spindle wire from the loom and running it on its own. The VFD creates massive interference on the rest of the loom.
Excellent. I will be delving into that soon. I wan't to see if I can get the EMI eliminated in my tests so that the signal wires can still be in the same location as the other cables, like the Spindle/VFD cable.
@@PatrickHoodDaniel get a common line efi filter for the supply side to the vfd and a choke on the spindle side. Clough42 did a really good video showing how this solves all the interference issues.
@@raindeergames6104 Excellent. I will watch that video. Thanks!!
@@raindeergames6104 I am currently watching that video. Thank you for the recommendation. I will be doing the VFD/Spindle tests in a future video. I may not setup the measuring method he is using (proper coil with resistor), but I will use the choke on the supply side as an added recommendation and cite his video. To measure the waveform, I will be using ABB drives instructions, but I will also be laying the signal wires in parallel to get a more "in context" EMI readings since this is what would be done in a real world scenario. Using the coiled up probe is an interesting idea though.
Hello! I have big problem od EMI im my car audio system. What you think about ferrite magnets to a wires ? Its can Help ? Thanks!
@@basserex4991 yes, that will work, but it would be good to find the source and shield that.
@@PatrickHoodDaniel With cheap (70$) RF Field Meter can i find easy source of this problems? Thanks !
I would check your ground. Make sure its sized correctly and check it with a meter.
@@basserex4991 Not sure. I haven't used an RF meter, but the idea sounds interesting. A handheld oscilloscope could also come in handy with car audio so you can get better access to all of the components. I would also echo what @-BlackBird7 said. Grounding is a big deal as I show in the tests.
@@PatrickHoodDaniel yes i have a osciloscope. The problem is with only one Amp. Waveform is very very dirty. Noised wave ( FAT wave) But signal RCA is clear. Amp is ok because i tried other Amps and problem is too but sometimes disconect power wires from amp can help back clear sinewave but problem is back. I think its EMI, antena, xenons and more. Its not easy :/
Do you wire to -v of the PSU or to earth ground.
Connecting the shield to earth ground is the best option.
Do you have a preference between ferrules and tined end wire? And is it due to one being more troublesome or just preference. Thanks for this vid
@@outrageousacres tinned end wire loses its springiness, but I have not tested this. I would love to test this on my Livestream.
21:34 that "stair stepping" is classic impedance mismatch between the cable and the receiver. With the limit switch closed, you essentially have a large loop, and the input on the controller is relatively high impeadance, so you end up with ringing in the cable that constructively interferes with itself as the interference from the motor leads bounces back and forth from one end of the cable to the other. If you put a resistor in series with the limit switch, that would go away. The tricky part is measuring the "characteristic impedance" of the cable - you need an LCR meter, and you need to measure the short circuit inductance and the open circuit capacitance of that cable, and then you can calculate the characteristic impedance, and terminate the cable with the correct resistor. Of course if you shield the cable, the noise induced from the motor wires never makes it in to the cable in the first place, so it's not going to ring like that, but terminating the cable properly will also lead to cleaner signals to the controller when the limit switch closes as well
Excellent comment!! Thanks!! I would have through a ringing would look more like a springing that acts like a transient response. Thank you for this education. I want to try the resistor in series on the next test. Without the use of a LCR meter, is there another way to test? Can I use the frequency of the stair step by measuring the period to determine needed values?
@@PatrickHoodDaniel Without an LCR meter, the only way is to use a fast edge generator, and a resistance substitution box (or a potentiometer), and try various values until the ringing goes away. To see an explanation of what's really happening, see a couple of videos by w2aew - "#37 use a scope to measure the length and impedance of coax", and "#88 cheap and simple TDR using an oscilloscope and 74ac14 schmitt trigger inverter". It doesn't matter that he's talking about coax, and you have plain wires - it's the same concept. Terminating the "bus" of high speed digital signals (at both ends) is also important to prevent ringing as well - an unterminated high speed digital line will destroy the signal integrity easily. Some of your explanations of what's really going on here are a bit shakey, but EMI interference is a complicated topic, and most EE's don't have good explanations either, unless they've specifically researched and looked into it (probably because they've run into signal integrity issues) as well. It's not a subject that's taught in typical undergrad curriculums, though it really should be, as CPUs and even micro controllers get faster and faster, it's very easy to run into problems.
@@PatrickHoodDaniel You could also try using a twisted pair for the limit switch - both shielded and unshielded. Just cut apart some ethernet patch cables for unshielded twisted pair. Ethernet twisted pair should have a characteristic impedance around 120 ohms, so you shouldn't need to measure it.
@@gorak9000 I like the idea of using a pot to ring out the ringing! Haha. I love these types of experiments. This is how I learn. I will make sure to watch those videos before the next tests. I'm sure this may merge into my uC videos some day. Loving your comments. Thank you so much!
@@gorak9000 I did get a comment on this video about that. I think I also mention it on my comment as well to add to my testing. Thanks again!!
2:18 Those have 2 channels! The third BNC is a external trigger input.
If you are not used to work with oscilloscopes I would strongly advise getting a portable or USB scope that has individual isolated channels because it's very easy to short things and blow up something if you are not careful (especially with bench scopes since all channels are grounded and earthed).
PS : NEVER try to measure mains voltage with a scope unless you REALLY know what you are doing.
Thanks. Will do. Part of the way I learn is by creating videos on the subject. I do not have many hours on an oscilloscope, so the comment is greatly appreciated. I want to get to know my PoScope a little better, so I will use that on the next tests.
I want to add that as per your comment, I am seeking more education on measuring 3-phase output for the VFD I will be testing soon. Even though I didn't talk about testing AC anything in this video, and not even elude to doing so, your comment came at the right time before I decide to test AC with my oscilloscope. Although, this scope had gotten a lot of use over the years and wouldn't have concerned me if it did fail due to my ignorance. It would have just caused me to get a better one, and do more research. Life is a great teacher.
Keith in the UK has written a book and he says that he has issues with wires going to end stops that aren't shielded causing issues . Keith has a TH-cam channel where he builds and flies RC planes using a CNC foam cutter. Thanks for the video
Thank you kindly for watching. That is probably due to the older 5V limit switch connections. I remember where the older parallel breakout boards used a few of the parallel pins to serve as inputs. Even with some conditioning, those signals are relatively weak. I remember many customers back around 2007-2014 or so needing to make modifications to avoid this. Shielding is definitely the way to go as an overall solid system.
Additionally, my explanation at 24:09 may be one of the issues many had because the signal wire had no path to ground depending on the NO/NC configuration.
Does shielding have to be bonded to the grounded enclosure to work?
Not absolutely, but it is best practice. I show this more specifically on this video: th-cam.com/video/5kHnuWQ2lr0/w-d-xo.html at timestamp 28:23. You can use the DC- to ground the shielding only if there is not other option. You should always shield to the body of the CNC enclosure.
Generally, DC doesn't create a huge amount of EMI. AC does as it generally has higher voltage (220v-240v) and frequencies (50-60hz) and this is what really causes noise, especially switching things on and off, which causes EMI spikes - the data lines act as an antenna, picking up those signals and causing step interruption.
Two sources I've found that really cause issues are AC spindles (my Kress brushed spindle is a nightmare) and my air compressor which uses an AC motor can flood the workshop with EMI. AC motors work by energising phases, effectively switching them on and off really fast and that is the source of the noise (think "switching" PSU - the clue is in the name)
@@GeeEmJay I will make another test with those components in a later video. Love the comment.
Whether in DC or AC systems, the process of switching-turning current on and off-creates sharp transitions in current and voltage. These transitions generate high-frequency components, which can radiate as EMI. The rapid switching creates harmonics that can extend into the radio frequency (RF) range, leading to interference in nearby electronic devices.
People often confuse pulsed DC with AC because both can generate EMI, especially when switching is involved. However, they are fundamentally different. AC naturally alternates, while pulsed DC involves periods of on and off states, leading to distinct types of interference.
It's the switching in both AC and DC systems that is often the root cause of EMI, not the mere presence of AC. This is why devices like switching power supplies, regardless of whether they are rectifying AC to DC or working within a DC system, are significant sources of EMI.
In a SMPS (switch mode power supply) it is not the AC part that creates EMI but the DC part where the switching occurs. Those are actually DC-DC converters since the AC is directly converted to DC and the voltage "conversion" happens in the DC part. This is also why they can work with DC input because they are actually a DC converters.
@@ppdan This is a really good comment and why I don't see the interference from AC cords. In my tests, I am trying to imitate where cables and wires would be placed in a typical CNC setup. The wires and cables may not come close to the actual devices like switch mode power supplies, but I can test these circumstances. What do you think?
best video ever for us hone builder’s
@@jesperhansen8777 thanks!!
My limit switches kept triggering from router noise. I put capacitors near the switch to hold a charge (with resistor at micro controller to charge). Never had a problem since!
Great topic btw. I wrote GatorCAM for cnc. It saves so much time! I'll give you a free key (it is NOT cloud , and no internet needed). On my videos.
@@TheRainHarvester Sure. Where in the world are you located? I use and offer CAMBAM because I know the developer (met him in the Austin MakerFaire in 2007). I am very interested in talking about software with people that care about the software.
That is great advice. I will try this in subsequent tests!
@@TheRainHarvester I just watched your video on GatorCAM. I also looked at the price! Why such a low price? Is this an introductory price until you have more features worked in?The V-bit lettering is a feature that is quite impressive and might be the only reason folks purchase v-carve, which is very expensive.
@@PatrickHoodDaniel I'm in central Texas. I'd like to talk to you! I've followed you since all your color-animal cnc inventions (since 2014?)!!
Maybe i should go up in price. But upgrades will be free for anyone getting in early.
I've got BIG plans for v-bit carving I think even the other expensive packages don't support!
I really do not like RENTAL software!!
Just watched corvette's video, that is 18 minutes i will never get back (twice speed), also read your looooong reply, i did not bother to comment on it at all as talking from a couch is useless, he should make a video but i sincerely doubt it. Your reply was very civilized, despite him not being much.
Regards.
Oh my god, why didn't I watch it at that speed!! Yeah, the couch thing... Ugh! I'm sorry you lost your time, butt I hope you were able to get some enjoyment out of my very long chit-chat.
@PatrickHoodDaniel thank you for your time to reply to all this, much appreciated, and for helping others.
I try to help people building cnc machines daily on the forum, where i find it quite difficult to properly explain shielding and grounding, and since you did a good job, i will gladly point them your way.
Again, thank you very much.
P.S. i have build logs of all my machines on the linuxcnc forum look for tommylight
A cross-hatch weave of all your wires around a core of 1/2 inch cotton rope will help mitigate any antenna effects, and is often used in high-end audiophile grade speaker cable for eliminating RFI signal noise. A second option would be to use a shielded coaxial cable, depending on how powerful the background EMI radiation environment is. And the third option for extreme measures is to not use copper wire at all and instead use fiber optical links, which except for the emitter and receiver are basically immune to EMI interference. That would be like in a case where your machine was operating in close proximity to a high voltage em field such as a high voltage transformer or Tesla coil.
Sounds like the building of an inductor with some extra twisting. Sound like a solid plan. The fiber optic opinion I sell with my plasma THC controllers. Those are definitely a good idea. Thanks for the suggestions!
@@PatrickHoodDaniel Really? Where do you sell these controllers, and would they work for say a drone application?
@@BrentLeVasseur buildyourcnc.com/item/electronicsAndMotors-electronic-component-plasma-thc-plasmaControllerAndSensor and buildyourcnc.com/item/electronicsAndMotors-electronic-component-plasma-thc-plasmasens-Sensor
@@BrentLeVasseur These are plasma controllers. Are you referring to cutting drone parts using a Plasma Cutter?
@@PatrickHoodDaniel If only I had a workshop where I could put that stuff, I’d love to get a CNC machine and plasma cutter. Unfortunately I live in a small two bedroom apartment.
Others have already suggested this but if you want a useful scenario you really do need to redo these tests with the spindle motor wires instead of the axis control control wires. The induced current from the spindle would be much greater.
Thanks for the comment and yes, I put this in my pinned comment for what needs to be put into the next video. I may make a series because different CNC technologies (Plasma, Laser, Spindle based, Router based, etc) has interferences from disparate sources and each deserves their own video.
I use ferite cores on my data lines and also have a metal enclosure with a dedicated ground which goes via an earth wire to a ground spike outside my workshop. All components in the enclosure have a connection to the ground bolt in a star configuration (dont hook up in series as you will get a ground loop!)
Thanks!! I briefly talked about the enclosure aspect at the end of the video. It is important. I will make a followup video on other aspect, including the enclosure, but I will also include the sue of ferite cores and coils for induction to reduce the higher frequency noise.
Are data lines really a big problem since they mostly don't run for big distances along motor lines?
Limit switches can be a real pain because those run along lots of stuff that can create interference.
To be honest, the only CNC I ever owned is a small table version that I used to make PCBs and the problem I encountered was that switching the DC spindle would "trip" limit switches.
@@ppdan No, data (or pulse) lines are not a big problem as that is why I didn't do those tests. However, the closed loop motors have encoder cables. These are always shielded and I have never seen them with ferrite cores, but that doe snot mean that they would not benefit from ferrite cores.
A twisted pair also improves rejection of external electromagnetic interference from other equipment.
Thank you for that recommendation. I may take a look at that if the interference in my future tests show that I need it.
Hi Patrick. Clinton here from South Africa. Hope you keeping safe during the storm. I have a quick question. I'm running Mach3, with a Mach3 usb controller card (the red one) do you have any videos on connecting a router or plasma cutter to this card (switching and pin allocation) did a quick browse and didn't seem to find anything. If so, could you please link the video? Thanks. And keep safe. Keep up the great work.
I do, but the video is in the members area. I have been moving some of the videos to the members area to benefit the paying members. However, I am happy to talk about it in a livestream on the Tuesdays and Thursdays that I focus on CNC stuff (1:00 pm Eastern). Hope to see you there.
My input- you looped the conductors for the motor back over themselves. That causes a lot of cancelation in the induced
field to the adjacent signal wires.
And yeah- a brushed spindle motor will make a much messier signal than the steppers because of the higher current and possibly higher dv/dt
Yeah, I got the same comments from others. I need to retest for those conditions. I will be testing with a spindle, but I wasn't planning on testing with brushed routers. There are still a lot of CNC router enthusiasts using routers, so maybe I should. It would make for some worst case scenarios. Thanks for the comment!
@@PatrickHoodDaniel thanks for the reply! Make sure it’s a brushed spindle (like I have on my desktop machine) because the commutator makes for very high dv/dt when it switches polarity!
hi i used this controller for my cnc. machine runs smooth but sometimes machine pauses, in the middle of g code running, for a second and resumes again without any warning or indication and randomly repeats that. sometimes it pauses and moves in wrong direction damaging the job and tool. i coudnt figure out the actual fault. i udes shielded wires too.
Not sure what the problem could be. The fact that it ran in the opposite direction tells me that the direction signal wire may have gotten interference, or is a loose connection. The direction signal is either high or low. If it was high, then the connection broke, it would go low (depending on how it is wires and if it is active high or active low.
I think you will find the "interference" at the millivolt levels is actually much lower than you saw.
The reason is your ground clip and the wire it is connected is a HUGE magnetic antenna.
Keep your ground ULTRA SHORT, using a ground clip on your probe, ...ditch the ground wire for these type of measurements!
@@stevenbliss989 thank you kindly for the comment. An incorrect ground probe setup doesn't explain the moments where I measure absolutely no interference. The same ground connection was used.
@@PatrickHoodDaniel You are right but he does have point. Always probe ground and tip as close as possible.
Also, while a normal x1 probe has no problem measuring signals up to 15-20MHz and your scope only has a 25MHz bandwidth (which is more than enough for what you are doing there), personally I use a x10 probe (or switchable probe switched to x10) to have less capacitive load introduced by the probe. But this is me and using a x1 probe for what you are doing there is perfectly fine. Just keep that in mind if you ever measure things at higher frequencies (especially square waves), a x1 probe has limited bandwidth.
PS : I have seen cheap x1 probes that would already struggle with 5MHz making square waves look like crap.
@@ppdan Yeah, I will definitey do this in my next tests. Thanks for the information on the bandwidth limitations for x1 probe.
Just came across your stream, very interesting. I am not sure of the reason of folding the test wires. I believe by doing so reduces induction along the wire’s length. Try testing without the single fold. The current flowing produces a field that is opposite the return wire, producing a zero field. We used to make bifilar coils that were effectively just resistors.
@@markcummins6571 Thanks for watching and for the suggestion. When I do another shielding video, I will look at that scenario.
Uur awesome. Thank you.
Thank you so much!!
Personally I think you would likely have a larger issue by testing the wires running next to the router or spindal wires. I believe that the noise of a brush 120v motor and a VFD spindal would cause a much greater issue on the wires, especially the switch wires.
I had a couple of issues when I had a brushed router motor on mine in the beginning. I ended up buying tome ferrite snap ons and snapping them on the router power cables, and it resolved the issue. I have a feeling that the Z axis which has all of the wires running to it is the most susceptible. The Z axis has a router, a stepper motor and a limit switch. All wires run to that. And the router power being parallel to those other wires I think is the most likely source of many CNC issues. Shielded wires to the Z axis is definitely the best option to eliminate those issues. Buy sometimes those ferrite snap ons can help in a pinch. Just my 2 cents
@@newmonengineering that seems to be a theme in the comments. I will definitely be doing that test.
@@newmonengineering Yes, I will be checking that out in coming tests.
Hi nice video! It would be interesting if you hooked up a plasma cutter or a vfd and did the same tests. Those are the two biggest noise makers that I know of. Thanks
Yes, will be doing a follow up video with a spindle. Thanks for the suggestion!
If I might make a suggestion, excellent and valuable video, shouldn't discount that in the beginning. Also, if you showed the worst case in the beginning, it would provide motivation to watch the rest.
Perfect suggestion!! Thank you
When I do my next shielding video as per the many comment suggestions, I will lead with a noisy reading.
But if you throw a high power spindle into the mix, that 5V USB controller has no chance. Maybe if shielded cable is used.
@@bergenbroodryk8103 bet! I will be doing that in a later video.
you have been a great resource on matters cnc. however, id ask that you edit your videos to appear more of a natural conversation instead of snappy clips put together. meaning no offense, but it makes it a bit difficult to follow along
@@brianxavier8873 haha, I don't think you would like to see that. There's like 5 minutes between each thought. One day, when I get more accustomed to being on camera, maybe the thought patterns will stick closer together. Maybe I'll invest in a teleprompter.
Run a plasma cutter with hf start next to this setup and you'll clearly see the weak shielding
@@hisheighnessthesupremebeing plan to in another video but will need a plasma first. Haha
@@PatrickHoodDaniel I would love to see that!
I find poor quality pick-up lines really aid in signal rejection 😂
For sure, but no puck-up lines is no rejection and no pick-up either. I don't have any experience in poor quality pick-up lines, but I once gave a girl a rose in a mall and that worked.
I commented under the other user name, the comment has disapered!
TH-cam, wtf?
Weird. Under which name?
@PatrickHoodDaniel toma . 3d
That is what i was loged in as
I also have toma . Cnc1
@PatrickHoodDaniel i added this video to linux cnc forum and asked if that is ok with you.
Lets see if this comes through.
@@tomaberisha5688 Great! Thanks! I love LinuxCNC. Before I got into using Mach3, I was a totally dedicated LinuxCNC user. I also used LinuxCNC for my pick and place machine with all kinds of awesome gcode coding. Much appreciated on the share.
@@PatrickHoodDaniel Again one of the replies disappeared with that user name, it hates user names i guess
And now it shows.....