As the standard size stepper would hit the frame now its mounted on the head.
The problem i have is two fold -
The stepper is getting very hot.
The stepper is stalling when extruding quickly.
I can adjust the driver on the control board to lower the current, which would probably reduce the heat issue, but am I right in thinking this will also lower the torque?
Is it probable this small stepper just doesnt have enough grunt ?
In general, it’s normal for steppers to get fairly hot when they are near the top of their design torque range, and yes, lower current means lower torque, and microstepping gives far lower torque than full stepping, so you might see periodic artifacts in your print from the resulting periodic change in pressure on the filament you are using that are more pronounced as you print faster. That additional heat can make acrylic get a little soft.
If you still have trouble with the new steppers, consider one of the new lightweight extruders that integrate a stepper, like the Orbiter.
To add a bit more context to the orbiter concept, it runs a NEMA 8 with a planetary gear reduction that’s close to 5:1. This means you keep the torque, but your top speed will become an issue.
Most of the extruders considered “top shelf” as complete units being sold generally have a 1:3 reduction ratio. This is specifically the case for E3D’s Hemera XS and Bondtech’s lightweight lineups.
Also keep in mind that whatever pressure you’re getting on a direct drive should be significantly lower than on a bowden. So perhaps you need to up the print temperature a bit to fluidify the filament to extrude faster? Or getting one of Bondtech’s CHT nozzles whose geometry will help a lot in reducing the pressure to extrude.
This would help you lower the current while keeping print speed and print quality at desired levels, if not directly increasing it.