Has anyone changed out to a longer USB cable on their longmill? I’ve been reading about all kinds of possible electrical interference causing issues, so I’m assuming that a well-shielded cable is in order.
I added an extension to mine and haven’t had any problems…yet. It adds about 2m of play until I decide where and how I’m going to integrate the laptop to the bench.
Tks much, br5d. I can get a 10’ shielded cable locally for less than $15, so I think I’ll give it a try.
Where the cable is located relative to noisy electrical parts is important. I would avoid having the USB cable near any of the stepper motors or the wires that lead to them. 10’ shouldn’t be bad, but I wouldn’t really want to go much longer than that.
Tks myklhn. It won’t be anywhere near the motor wires. It will be underneath the table.
Shielded stepper motor cables should be on the list of improvements for future upgrades.
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They already are the casing that is on them in a type of shielding I thought. Besides the USB cable don’t go any where near the stepper wires. There is nothing to worry about even if it was.
I don’t have my machine yet so I’m just going by pictures and video. It looks like the cables have a plastic or fabric braiding. If this is true, this will provide mechanical abrasion protection but not electro magnetic interference (EMI) protection. EMI can cause all kinds of havoc with electronics. Plywood offers no protection whatsoever. A source of EMI can radiate through the plywood/MDF and cause noise on a USB or other type of cable. What does help is physical distance between cables, cables not running parallel to each other and crossing at right angles. The best protection is proper shielding.
The guys at sienci labs have done all kinds of testing to find EFI and only found that very high pressure use of the router generates enough EFI to cause problems with the switches on the control board. That has been fixed. This is getting over blown now. Stepper motors this small wouldn’t cause much at all. The router on the other hand could but that has been found to only cause one problem on these machines as far as I know. So unless you have a tester to see how much is coming off the machine and can post a pick of the levels of the read out and have empirical proof EMI is happening then lets leave this be ok? These machines have none or very little other than that router. Wrap it in tin foil if your worried.
Just because you read it on the internet doesn’t make it so in every situation.
My experience was first-hand. I had to move the USB cables away from the wires driving NEMA 23 motors to avoid some skipping. The machine I had didn’t have any shielding and I wasn’t using the highest quality USB cable (not the lowest, either). I was getting intermittent missed steps that was causing the quality of the work to get worse and worse. Once the USB cable was re-routed away from the stepper motor wires, I stopped having issues. In any case, I would avoid having signal cables routed near power wires (the motor wires).
I’m going to try to learn more about this. If anyone here knows, or can point me to good sources, I’d really like to learn. In my case, I get intermittent freezing. Andy has been good about contracting me and trying to diagnose the problem, but since it is intermittent, we do not have any definitive answers yet.
Andy did explain that they have included capacitors in the controller to filter out noise.
I am not so much concerned about the USB cable as it is no where near the stepper motor cables. With my admittedly very limited knowledge, I just wonder about having the router power cable in the drag chain with the stepper motor cables. I imagine that the beta testers had the same set up, as, I expect Andy and Chris did in their testing. However, it does not seem unreasonable to me to wonder if the power cable on my router is leaking more than the LongMill can accommodate.
I have absolutely no evidence to prove that this is the problem with my machine, but lacking any other explanation, I’m not going to rule it out, either.
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Greg: To be clear, I’m not talking about a problem between the USB cable and the stepper motor cables. Like yours, my USB cable is no where near the motor cables except for the short distance between them at the controller.
I was referring to possible interference between the power cable to the router and the stepper motor cables. In my case, I followed the installation instructions that have the power cable running in the X axis drag chain touching the X axis motor cable, then running in the Y axis drag chain, touching one of the Y axis motor cables.
Do you run your router power cable in the drag chains with the stepper motor cables?
So far, I can’t tell if this is causing my intermittent problem, as the problem is intermittent. I’m continuing to run practice jobs to see if I have solved the problem.
Yes my power cable for the router is in the drag chain with the stepper motor and I have had no trouble at all. So I don’t know why you guys are having this problem at all. Or if someone made this up and threw it on here to start an argument! There is no interference at all through this. If that was a problem everyone would be having the same problem. Including Chris and Andy at the shop. Their machines are set up the same way.
I can’t speak for anyone else, but I sure has hell am not making anything up! Nor am I trying to “start an argument” as you seem to be doing here.
I respectfully submit that you cannot possibly know for a fact that none of the router cables is causing interference. You’ve just said as much yourself in saying that you don’t know why we are having this problem. I don’t either. I’ve never said that my router power cable is the problem. Like you, I don’t know what the problem is. I am merely trying to determine why my LongMill freezes. That is does freeze is a fact. It is not me trying to provoke an argument.
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I don’t mean you are for sure no problem. I don’t mean to say you are no problem. I know its frustrating.
I saw a vid for another brand CNC. Guy was having issues with the machine
jamming out in the middle of jobs. He ended up running an extra ground from
router all the way back to power source.
im not sure you can with these palm routers can you? Wouldn’t that make more electrical interference? Did your router cord have one of those things over the cord? Those plastic looking sleeves? They are supposed to dampen noise from the router. Was that missing?
I’ve been reading much more than I want to on the whole question of electrical interference. I now know all the buzz words and understand little more than I did before I started all this. 
In other words, I know just enough to know that I know almost nothing. (That’s a lot of “know” in one sentence, yes?)
One thing is clear. It is a fact that it is possible that magnetic fields caused by electricity flowing through wires can cause noise on other, nearby wires. I emphasize that I am not saying this is the cause of my Long Mill freezing.
As Lumpy said, there is a lot of information available about grounding wires and isolating wires. However, it is not as simple as simply adding a ground wire. I wish it were. You get into ground loops and all kinds of other complications that mean the simple addition of another ground wire may not solve anything.
I know that Andy and Chris took some of this into account in the design of the Long Mill. Andy told me that they installed capacitors to address noise. Andy never said, at least to me, that it was therefore impossible that electrical interference was causing my freezes.
Greg said in an earlier post that the problem of the router causing issues “has been fixed”. I’m assuming that is a reference to the capacitors that Andy told me they added. Andy did say to me that if one of the capacitors was not installed correctly, “one of the buttons could be cancelling the job”. My next step, now, is to send Andy screen caps of UGS when the next freeze occurs. They may tell him if this is what is happening.
To address Greg’s question, I’m not sure what sleeve you are referring to. My router has the usual strain relief where the cord enters the router. However, that is not there for noise reduction. I’m sure that you know this, though, so you are referring to some other sleeve. In that case, mine does not have it.
Just out of curiosity does your router cable have any nicks or cuts or chunks or divots which would theoretically reduce the thickness of the cable and possibly reduce the shielding of same. I know that my Makita is 8 or so yrs old but fortunately I’m not having any of the issues that are plaguing yourself.
Tks for your input, Br5D. I didn’t see any issues with the cable before I put it into the drag chain. The router is brand new out of the box. I have never used it for other woodworking projects. (I have had a Bosch for a long time.)
I have not yet removed the cable from the drag chain. I’m still trying some software solutions. So far, I’ve not had a freeze in about a week. I am trying to duplicate as near as possible the conditions where I have had freezes before, so that I can cause another one. I’m not being an ass in trying that. I didn’t think to get screen caps with previous freezes and Andy needs them to help me diagnose the cause.
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