Onefinity Controller Stopping Mid-Program (solved: EMI / Static Build up)

If you have a multimeter you can check it the way I described in the other posting.

Probably. Magnet probe is ground. What is the exact error you see?

@Aiph5u
I will be a couple days before I can get back in the shop but I will test it out and get back to you.

It appear you are correct. See attached video. Two wires appear to have a short. I checked the other Y rail and did not get continuity on that one so that is plus.

Note this video is unlisted and only available via this link.

Also this is the error I am getting. When the probe attached to the rail.

Hey John,

if you are sure that there were no other contacts present (short through your body, (fingers)), you will have to proceed with step 6 :frowning:

What was the Ohms range you’ve set the multimeter?

I think it is automatic :woozy_face: So not sure.

I am not very experienced with a multimeter.

For hunting this issue, I would start with megaohms, and see if the resistance is stable, and then go smaller. If the number shown on display is not stable it is either out of range or you have oil on the rails or something which disturbs contact. Best would be to clamp one measuring tip to rail or foot with a clamp.

Note that like when Darren had this issue, as long as only one stepper wire has a short with rail or foot, the machine still might work without issues. It’s when you ground the machine that the issue shows up. Or when two or more stepper wires have a short through rail/foot. In the first case the motor error shows up when you ground the rail or foot, in the second case possibly always.

In both cases any short between stepper wire and rails is a fault.

Further Reading

How to Wire Stepper Motors
DRV8711 - Texas Instruments

Yes machine seems to work okay for awhile. Since i got it though I have been having issues with interference on the screen since I got the machine. It flickers and goes out. I have also had a lot of issues with disconnections. I contacted support about this previously and they said it was a software issue and the upcoming patch would fix it but the recent patch didn’t fix my issue. They also sent out a new controller for a different issue at one point and I am still getting the screen flickering and disconnections.

Yes I saw that issue Darren had. I wonder how common this is?

Thank you for the light reading material :sweat_smile:. I have contacted support as I am hoping they will send out a new harness that I could swap out. The harness I got with my X-50 rail was an improvement over the original harnesses.

If you don’t mind me asking @Aiph5u what is your day job? You seem very knowledgeable on this subject.

Hey John,

to access Inner Rail Tube Motor Wire only after having received the replacement wire is wise :slight_smile:

Something totally different. But with electronics I got heavily infected during childhood and they haven’t found a vaccine against it since then :slight_smile:

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Hey John,

attaching the magnet probe to the rail should in no case trigger a motor error.

I agree. Support has asked me take the rail a part.

Hey John,

besides cables being pinched between rail and end cap making a short this way it is also possible that a crimped wire became loose from its pin at the connector that is inside the rail.

Hey John,

when I looked at the video describing this (Support : How to Access the inner tube motor wire), it was clear that of course you don’t have the rails lying around like this, but that you have an assembled, working machine. I just had the thought that if there is ever any concern about the cables inside the rail, it would be good when planning a table for the Onefinity CNC to have a service hole under each front foot which would allow access to the screw that loosens the end cap (which allows to remove the cable then).

And my second thought is, why don’t they have light at their film set? (Or at least why doesn’t someone click on the brightening/contrast button in their post-production software?)

Screenshot__Howto_Access_the_inner_rail_tube_motor_wire__before_50pct

Screenshot__Howto_Access_the_inner_rail_tube_motor_wire__after_50pct

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Lol I thought about drilling a hole thru the bottom my table as it is only a temporary table but I am not confident in my drill stops and I am concerned I would plunge it into the bolt making the problem worse.

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Hey John,

May I recommend you these ingenious Star-M Depth stops :slight_smile: :

Star-M No.5005 Drill Stopper

The plastic cap rotates freely and stops rotating when you reach desired depth. I use a set of them, from 3 mm (=approx. 1/8″) drill diameter upwards. Picture shows ⌀ 15 mm drill (=approx 19/32″).

Available here or here

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I am not that patient. I opted for the good ole blue tape method but here is what I found.

Hey John,

according to the motor error appearing when attaching the ground probe to rail, and according to your resistance measurements, this is exactly what is expected to see. These blank wires short one or more stepper cables to the rail. It is similar to the image Darren posted the other day. This is an assembly fault.

So did I.
Onefinity has a replacement in the mail. I am surprised the red wire even functioned with how it is pinched.

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Hey John,

so now next challenge is to achieve what they didn’t achieve at the factory: To get the cable into the tube without pinching it again! I think the cause of this issue is that the cables are rigid, and the tube is small, so what shall the cable do when you push it? Everyone already pulled a cable, but did you ever try to push a cable? :slight_smile:

If you don’t plan anything special then it will kink because of its overlength compared to rail tube, but where will it kink? Well, without further ado it will again crease at the inner edge of the end caps. I haven’t tried it, but I don’t think it’s that easy.
I thought to myself, how would you have to do it so that it doesn’t bend and get stuck at the front? Exactly, you would have to give it a helical shape, and this before you even put it in.

By wrapping it, somewhere further back a few inches, around a cylindrical object, maybe like this:

wire_helical_winding-000

You remove the cylindrical object after that of course, it’s just to give the cables a little helical shape. It is shown a little exaggerated, you don’t want to create an electrical coil, but you have to ensure there is a predetermined position where the overlength of the cable will go when you slide it into the rail.

And then, when doing this, additionally it would be best to put the front end of the cable in a small tube about 3-4 inches long so that it cannot kink at the front under any circumstances, and put the end caps around the connector only at the last moment. The small tube would have to be larger than the connector so that it can be slipped over it, but small enough to be inserted into the rail tube as an insertion aid which you remove in the last moment. Or even let it remain in there.

What do you think of it? Can you report how it goes when you try to install the replacement cable?

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So it wasn’t much of an issue to reinstall the cable. It had an enough stiffness that I was able to gently feed it thru the back to front. Then I just snapped back on the cap piece and gently pulled on the wires in the back as reinserted the cap.

The wires are pretty precise length so there would likely not have been sufficient length to wrap it around a tube.

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Hey John,

thank you for reporting this. Is the new cable shorter than the older one?