The flexible conduit attached to the X-axis motor on my PCNC 770 is broken at the motor connector. Is there a way to detach the three pins from the quick-connect plug at the panel so that I can pull the motor cable out of the conduit without cutting the cable?
Hi Andrew,
Unfortunately, there isn’t a great way to replace the conduit without removing the connector on the other end. These are soldered in and would require you to desolder them. If you’re a wizard with the soldering iron, it shouldn’t be too difficult, but I know firsthand that it can be tedious.
If you do decide to take this on, I’d recommend taking a picture of the wires on the back of the connector before starting; this way, you can ensure everything gets back to where it belongs when you’re done.
Thanks. Desoldering it wasn’t too hard. I used a “helping hand” to grip the pin I was working on in hopes it would help prevent the plastic connector from melting. I don’t know if it made a difference but it did work.
How can I prevent the new conduit from breaking in the same place? For example, could I replace it with an all-plastic conduit rated for continuous flex? If so, what size conduit would fit the existing connector?
I suspect part of the failure has to do with the sharp bend the conduit makes right out the motor. Somewhat necessary to make sure any coolant drains off rather than seeping into the connector or motor. Perhaps some form of strain relief to help support that bend and keep it from moving as much would help?
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That’s an excellent idea. I know I’ve seen a picture somewhere of this very thing. Is there already a tapped hole on the underside of the table, or will I need to somehow make one?
That I don’t know. I don’t have a 770 to refer to.
The OEM conduit for the X-axis motor is standard 3/8” trade size liquid tight flexible metallic conduit. Tormach’s website lists it as “16mm”, but the motor-side fitting is marked “3/8””, confirming that this is not a unique size. You can get replacement conduit at popular online vendors.
The motor-side fitting is unusual. I think it’s got 1/4” NPT threads, but I don’t have an NPT thread gauge.
The original PCNC 770M S3 X-axis conduit is about 4.5 feet long. I only bought 1m of conduit, thinking that was about right. It is much too short and it will break if I try to move the table to the front left corner.
Learn from my mistake! Order at least 5 feet or 2m of conduit.