Should these connections get hot?

Hey Bill, hey all,

the question is what they could have used instead.

Onefinity obviously took over the connectors choice from the buildbotics.com project (so it’s them who made that choice), by first using their pcb layout and then modifiying it only slightly, leaving those Molex/Amphenol sockets there.

I’ve shared my thoughts on a possible choice for better stepper connectors here, and if I go with reputable industry connectors, it gets very expensive very quickly. That surely was out of the question for the Onefinity designers, which obviously had to realize a low price of entry (not to say some sort of combat price)). It would have not been of any advantage to them if you can throw the direct competitor products in the trash, but deterred potential buyers with too high a price. So they designed a machine that realizes an unusual, robust and handsome concept in the mechanical components (which led to their success), but lacks a lot of components, or the sufficient quality of those: A CNC without a machine base (you have to build the table – & the QCW frame introduced later is extremely expensive for what it offers), no serious cable routing, no milling motor, no homing sensors but using stall homing instead (which the buildbotics’s internal stepper drivers already provide for free), etc.

They realized the low price they needed, and had a great success, with many owners of other hobbyist CNC machines selling their old machine to buy a Onefinity, but the hassle of failing cables and connectors, which often comes after a year of use (=of motion without connector strain relief, or with a Z stepper cable that is not made for permanent motion), or the susceptability to positioning errors or step loss caused by electromagnetic interference (EMI) because of using unshielded cables, are a heavy legacy. I wouldn’t put the machine to work like this, at least not when I’ve spent relevant amounts of money on my wood blanks (which is easily the case in professional context – think of violinmaking and luthery).

1 Like