So lets say I wanted to build a lowrider and right now my side gig sales are slow, so hobby cashflow is down. If I repurpose some smaller nema17’s off an old printer that aren’t the 80 oz ones - maybe 40’s?, will they still work… at least long enough to prove out the electronics and prints and cut foam?
I have a door to mount this thing. I’m debating whether it should be long x or long y. if the x axis is the long side, then it could be mounted on a larger table and be potentially full size: not sure which orientation is the most efficient use of space. Open to thoughts.
Yes. They just wont have near the power. But should work for shallow slow DOC. Try to pair same/equal motors for the Y and Z axis though. That way you don’t have one side pulling harder than the other.
So the LR part list has a 24 V power supply on it. I run my primo with a 12V supply and this will have the same control boards and similar motors. Will 12V be a deal breaker (computer power supply) on the lowrider?
12v will work fine. You just take another hit on the power to the steppers. When you do plan to upgrade your steppers later I would also upgrade the power supply to 24v
This makes practically no difference in most operation of the machine.
The stepper drivers regulate current to the motors by effectively limiting the voltage driving the coils. This is a little more complicated than that, but it’s the general idea. Most of the time this effective voltage is under about 4V.
The reason we use more is because all electric motors are also electric generators. Of course the power generated is opposite the power used to drive the motor, so as the stepper motor turns, it generates voltage opposite to the voltage used to drive the coils. The faster you drive the motor, the greater the voltage generated. I had it worked out what speed we started to need the full 12V at in order to maintain 1A current with the V1 supplied motors, but they’re different motors now, and I don’t have the actual number ready to hand, but it was greater than 3000mm/minute, which is the fastest I use any cutting tool. (Basically, I calculated the motor RPM which would generate greater than 9.2V back EMF – given that 2.8V produces 1A current – and applied that to 32mm/revolution.)
Rapids, OTOH, I do go faster than that, but I also use 24V power, and so I never have a problem.
Anyway, the upshot of all of this is that 12V power is unlikely to cause you a problem with the usage of any V1 CNC. 24V allows faster rapids, and maybe allows faster movement for lasers, but this won’t cause you a problem with a router or spindle.
I can echo what Jonathan said. All my LowRider use until now (both on LR version 2 and LR version 3) was all on 12V. Now on v4, I’m finally switching over to 24V.
My understanding is the main potential benefit of 24V is faster rapids (jogs / travel in between cuts). 12V is very capable on LowRider.