MDF Rose Engine Lathe 2.0

Preferences Screen

Touch the buttons on the screen image to the right to see the details for the that screen.

Purpose: The factors on these screens control how speeds and distances are determined.

The values shown in a tan box show values on the Nextion. Touching one of the text boxes allows you to edit that value using the Number Pad screen.

The values shown in a gray box show the ones stored on the Teensy controller. These are read only and should match the settings on the Nextion.

Based on which screen is used to drive the B Axis movement these settings may or may not matter.

Screen	Comments
Main One	The speed setting (the right slider) on the respective screen is used to set the rate of motion. There are no limits to the range of motion; however limit switches may be used on these two screens.
Grk Mov Rec Sync	Each these screens has fields to set the radius the distance from the center of rotation to the cutter. and the distance for the movement around the B axis (the length of the arc). The fields and settings below are used to calculate how long to run the stepper motor to achieve the desired rotation.
Geo Ind	N/A: B-Axis movement is not possible on these screens.

Microsteps

This must use valid values for the stepper driver, and is usually 1, 2, 4, 16, 32, 64, or 128. These settings must match the switch settings on the stepper motor driver (when using the StepperOnline DM542T) or jumper settings on the PCB (when using the Pololu DRV8825).

32 is the designed value for the MDF Rose Engine Lathe 2.0 (as outlined in Instructions for Building the Stepper Controls).

Steps/360

This must use valid values for the stepper motor. The typical step angle is 1.8°, so this would be \[ \frac{360 °}{1.8 °} = 200 \] 200 is the designed value for the MDF Rose Engine Lathe 2.0 (as outlined in Instructions for Building the Stepper Controls).

Polarity

The Polarity High and Low radio buttons for both Spindle and Z Axis are set as:

High		High setting is for use for some external stepper drivers
Low		Low is the default, which is the correct setting when using the StepperOnline DM542T or the Pololu DRV8825 Stepper Drivers.

Radial

Used when the rotation is achieved using a worm drive.

Gear Ratio

This is the gear ratio between the drive gear and the driven gear. In this case, 150 roations of the drive gear (AKA, the worm screw) is required to achieve 1 rotation of the driven gear (AKA, the worm wheel).

When configured as a radial axis for a spherical device it uses a calculated distance along the circumference based on the radius length between the spherical device pivot point and the cutter. The B Radius text box will appear on a page when the B axis is active and the B axis is set to Radial.

150 is the default value.

Linear

Used when the rotation is achieved using a threaded rod (AKA, a leadscrew) pulling against a fixed point (i.e., a nut) which is levered away from the axis of rotation.

Distance / 360

Faster Movement

Slower Movement

This is the distance the fixed point (i.e., a nut) moves with each rotation of the threaded rod.

Note: when using linear movement, the rate of rotation varies as the fixed point moves (as outlined in the pictures to the right).

0.1 is the default value.

Leadscrew

Used to identify how the direction selection on the respective screen rotates the leadscrew to achieve the desired movement. If it moves "backward" from what you think it should be, set it to be the opposite handedness.

Left Hand		Used when the threads are left handed.
Right Hand		Used when the threads are right handed.

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Strongly recommend you take care when changing these.