Sorry, I think this is a very basic question but one I haven't found an answer to yet. I was thinking of using this motor (17HS19-1684S) for all but the extruder on the X carriage. And I thought to use this motor (17HS15-0404S) as the extruder motor because it is considerably lighter. But it draws 0.4A while other motor draws 1.68A. Can these two motors be run at the same time off the same RAMPS. 1.4? And if they could, is a motor with 40Ncm (56.7oz.in) holding torque strong enough to turn a Wades small gear which turns the big Wades gear? Thanks for any help https://reprap.org/forum/read.php?13,369957,369957#msg-369957 Wed, 10 Jun 2026 06:14:04 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?13,369957,370303#msg-370303 https://reprap.org/forum/read.php?13,369957,370303#msg-370303
The machine is in the design stage and I'm not yet able to make the final weight calculations for the X and Y axes. I am trying to balance their weights as much as possible. If there is little weight benefit from using the smaller motor on the extruder the machine will still benefit from the shorter motor depth.

It's a modified Wades style geared extruder so torque from the smaller motor should be OK. All motors except the extruder will be the same. Just the extruder motor will be a smaller size.

I will order these motors.

Thanks again,


Garry]]> Garry Bartsch Controllers Sun, 15 Jun 2014 18:29:38 -0400 https://reprap.org/forum/read.php?13,369957,370288#msg-370288 https://reprap.org/forum/read.php?13,369957,370288#msg-370288
For a machine with independent x and y, like a moving bed, there is a moving assembly on x and another moving assembly on y. Only the one with higher mass counts for getting benefits via weight reduction. E.g. i dont know what is your situation, you should probably try to evaluate which of your axes weights more, the bed or the extruder carriage. If the bed weights more, a further weight reduction on x carriage does not bring benefits. If the bed is lighter than the x carriage (incl extruder), then it is the case that lighter x would be beneficial.]]> NoobMan Controllers Sun, 15 Jun 2014 17:56:25 -0400 https://reprap.org/forum/read.php?13,369957,370223#msg-370223 https://reprap.org/forum/read.php?13,369957,370223#msg-370223
I have not bought the motors yet so I looked for different ones. I found a larger and a smaller motor from the same company both rated 1.68A

Larger Motor

- Motor length: 48mm
- Rated voltage: 2.8V
- Current/phase: 1.68A
- Resistance/phase: 1.65Ω
- Inductance/phase: 2.8mH
- Holding torque: 4.4kg.cm
- Mass: 0.35kg

Smaller Motor

- Motor length: 40mm
- Rated voltage: 2.8V
- Current/phase: 1.68A
- Resistance/phase: 1.65Ω
- Inductance/phase: 3.2mH
- Holding torque: 3.6kg.cm
- Mass: 0.28kg

Aside from size (and thus torque) they have identical specs EXCEPT the inductance/phase. The larger one is 3.2mH and the smaller is 2.8mH. Will that stop the two motors from being working together in one machine? Driven by the same stepper drivers?

I'm hoping so since I'd really like to use a smaller/lighter motor for the extruder. The smaller one has only 18% less holding torque and I am assuming that it will still drive the gears adequately.

Thanks again]]> Garry Bartsch Controllers Sun, 15 Jun 2014 15:36:24 -0400 https://reprap.org/forum/read.php?13,369957,369992#msg-369992 https://reprap.org/forum/read.php?13,369957,369992#msg-369992 NoobMan Controllers Sat, 14 Jun 2014 22:37:32 -0400 https://reprap.org/forum/read.php?13,369957,369957#msg-369957 https://reprap.org/forum/read.php?13,369957,369957#msg-369957
I was thinking of using this motor (17HS19-1684S) for all but the extruder on the X carriage. And I thought to use this motor (17HS15-0404S) as the extruder motor because it is considerably lighter. But it draws 0.4A while other motor draws 1.68A. Can these two motors be run at the same time off the same RAMPS. 1.4? And if they could, is a motor with 40Ncm (56.7oz.in) holding torque strong enough to turn a Wades small gear which turns the big Wades gear?

Thanks for any help]]> Garry Bartsch Controllers Sat, 14 Jun 2014 20:07:18 -0400