Posted by:
roger wilson
(---.hsd1.mn.comcast.net)
Barry,
In order to reverse the direction of a sewing machine motor, you need to reverse the orientation of the brushes with respect to the armature. To do this, you need to bring out the brush wires and the armature wires.
You then need to insert a switch, so that you can swap their orientation.
In many motors, it is impossible to do this, because of how the wires in the armature and brushes are buried inside the motor. In other motors, the wires are easily accessible and very easy to access for switching.
---
Another good option is to remove your motor, throw it away and replace it with a DC motor.
Then, power the motor with an adjustable DC power supply. Then, when you want to reverse the direction of the motor, you simply insert a cross wired double pole double pole switch to reverse the input voltage to the motor. Any DC motor can have its motor direction reversed by simply swapping the input leads to the DC power supply.
I have built all of my power wrappers using Pittman DC gear motors. I have used motors ranging from 300 to 1000 rpm. Then, I simply use 1:1 pulleys to drive my wrapper headstock. Very compact, quiet, and easily reversible.
If you have any further questions, drop me a line at
hflier@comcast.net
Take care
Roger
