[kwlug-disc] OT: Below freezing cables ...

[Andrew Kohlsmith (mailing lists account)]

> On Jan 9, 2019, at 9:03 PM, Khalid Baheyeldin <kb at 2bits.com> wrote:
> The reason I suspect bad connections is that I changed the controller to a backup
> board that I have. Same result. Then other RJ45 cables. Same result. 

If you can, throw the motors and mechanicals in your deep freeze for a few hours and then, inside where it’s warm, try to operate it.
 
> What about the stepper drivers, are they marginally sized and higher current required for stepping in cold temperatures is causing them to fault?
> 
> They are tiny. NEMA 11 instead of the usual NEMA 17. But they have an 18:1 
> gearhead which gives them enough torque, and there are others who are using
> the same model of motors without issues (not in sub zero temperatures though).

Any grease or other lubricant used in the gearboxes which may become stiff or become more viscous in the cold?

> I did buy the flat RJ45 cables and the sockets, from eBay, so they may not be the best 
> out there.  But they are the flat ones, which are the most flexible. 

Mine come from Sayal, which I’m sure is also very poor quality. I guess if you had a way to perform a cable test in the cold it would make quick work of this theory. 

If it’s skipping and generally misbehaving and you go out and shove the cable into the socket, holding it there while retesting, does it still skip?

-A.


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