README.md

@@ -1,259 +1,3 @@
-# sv06-belt-recovery-stress-tests
+# motion-diagnostics-suite
 
-Belt tension recovery and motion stability test models for bed-slinger 3D printers (e.g., SV06-class machines).
+Parametric OpenSCAD models and procedures for diagnosing layer shifts, belt tension, and motion instability in FDM 3D printers.
-
----
-![](img/DSC_5098.webp)
-## Purpose
-
-These models are designed to help recover from situations where printer motion accuracy has been degraded, typically due to:
-
-* Adjusting belt tension without a reference baseline
-* Experiencing layer shifts during prints
-* Replacing belts or modifying mechanical components
-
-This project provides:
-
-* Parametric OpenSCAD models
-* A structured test procedure
-* Guidance for interpreting failure modes
-
----
-
-## When To Use This
-
-Use these tests if you observe:
-
-* Sudden layer shifts (e.g., 3-5 mm offsets)
-* Inconsistent dimensional accuracy
-* Audible belt skipping or motor stutter
-* After adjusting belt tensioners
-
-Here's an example of a case for a hand held radio where the top suddendly shift at the 20mm height.
-![](img/20260318_215156_Wed.png)
----
-
-## Models Included
-
-### 1. Cube (Baseline Test)
-
-* Dimensions: 40 × 40 × 40 mm
-* Purpose:
-
-  * Verify basic printer stability
-  * Detect gross mechanical issues
-
----
-
-### 2. Y-Bar (Axis Stress Test)
-
-* Dimensions: 20 × 150 × 50 mm
-* Purpose:
-
-  * Stress the Y-axis (bed movement)
-  * Detect belt slip under momentum and direction reversal
-
-**Important:**
-
-* Orient the 150 mm dimension front-to-back on the bed
-
----
-
-### 3. Tower (Long-Duration Test)
-
-* Dimensions: 18 × 18 × 120 mm
-* Purpose:
-
-  * Reveal issues that appear only over time
-  * Detect cumulative drift, resonance, or late-stage layer shifts
-
----
-
-## Print Procedure (Recommended Order)
-
-Run each model as a **separate print job**:
-
-1. **Cube**
-
-   * Confirms system is not fundamentally broken
-
-2. **Y-Bar**
-
-   * Directly tests axis tension and inertia behavior
-
-3. **Tower**
-
-   * Tests stability over time and height
-
----
-
-## Suggested Slicer Settings (Orca Slicer)
-
-### Cube
-
-* Layer height: 0.20 mm
-* Perimeters: 3
-* Infill: 20-25% (grid or gyroid)
-
-### Y-Bar
-
-* Layer height: 0.20 mm
-* Perimeters: 3
-* Infill: 15-25% (grid recommended)
-
-### Tower
-
-* Layer height: 0.20 mm
-* Perimeters: 3
-* Infill: 0-10%
-* Brim: optional (only if adhesion is an issue)
-
-See the settings folder for settings used in Orca Slicer.
-
----
-
-## Belt Tension Guidance
-
-This project assumes GT2 belts (typical for most hobby printers).
-
-### Frequency Method (Recommended)
-
-Using a phone-based spectrum analyzer:
-
-* Target range: **90-110 Hz**
-* Reference: ~110 Hz ? ~2 lb tension (Voron baseline)
-
-Procedure:
-
-1. Move bed so belt span ~ 150 mm
-2. Pluck belt
-3. Measure frequency
-4. Adjust tensioner
-5. Repeat until stable
-
-### Notes
-
-* Too loose:
-
-  * Low frequency (<70 Hz)
-  * Layer shifts likely
-
-* Too tight:
-
-  * High frequency (>120-130 Hz)
-  * Motor strain, possible missed steps
-
----
-
-## Interpreting Results
-
-### Good Result
-
-* Clean vertical alignment
-* No sudden offsets
-* Consistent layer stacking
-
----
-
-### Failure Modes
-
-#### Sudden Layer Shift
-
-* Cause:
-
-  * Belt too loose
-  * Pulley slipping
-* Action:
-
-  * Increase tension slightly
-  * Check motor pulley set screws
-
----
-
-#### Repeated Shift at Same Height
-
-* Cause:
-
-  * Mechanical obstruction
-  * Cable snag
-* Action:
-
-  * Inspect motion path
-  * Check wiring harness clearance
-
----
-
-#### Gradual Lean / Drift
-
-* Cause:
-
-  * Frame or axis alignment issue
-* Action:
-
-  * Inspect rails, wheels, or rods
-
----
-
-#### Ringing / Ghosting (No Shift)
-
-* Cause:
-
-  * High acceleration
-* Action:
-
-  * Reduce acceleration (not a belt issue)
-
----
-
-## Notes on Methodology
-
-These tests intentionally:
-
-* Emphasize repeated motion in one axis
-* Increase inertial load with height
-* Create conditions where marginal tension fails visibly
-
-This approach isolates motion system issues rather than general print quality.
-
----
-
-## OpenSCAD Usage
-
-Generate models:
-
-```bash
-openscad -D 'model="cube"'  -o cube_$(date +%Y%m%d_%H%M).stl  stress_test_models.scad
-openscad -D 'model="ybar"'  -o ybar_$(date +%Y%m%d_%H%M).stl  stress_test_models.scad
-openscad -D 'model="tower"' -o tower_$(date +%Y%m%d_%H%M).stl stress_test_models.scad
-```
-
----
-
-## Provenance
-
-Generated with:
-
-* OpenSCAD
-* Orca Slicer (recommended)
-* Frequency-based belt tuning derived from:
-
-  * Voron Design tuning methodology
-
-This project was developed with ChatGPT.
----
-
-## License
-
-Recommend: MIT or CC-BY 4.0 for broad reuse.
-
----
-
-## Contributing
-
-Improvements welcome:
-
-* Additional test geometries
-* Axis-specific stress models
-* Automated calibration workflows
-
----

openscad/stress_test_models.scad

@@ -147,48 +147,8 @@ module rounded_box_uncentered(x, y, z, r) {
                 square([x, y], center=false);
 }
 
+
 module place_top_label(txt, x, y, z, center_it=false) {
-
-    // --- parameters ---
-    margin = 2;  // mm clearance from edges
-
-    // usable space
-    usable_x = x - margin;
-    usable_y = y - margin;
-
-    // choose orientation: run along long axis
-    rotate_text = (y > x);
-
-    // limiting width after orientation
-    limit = rotate_text ? usable_y : usable_x;
-
-    // crude text width estimate factor (~0.6 * size * chars)
-    est_char_width = 1.0;
-    est_len = len(txt) * est_char_width;
-
-    // compute size that fits
-    auto_size = limit / est_len;
-
-    // clamp to your preferred max size
-    final_size = min(label_size, auto_size);
-
-    // placement
-    tx = center_it ? 0 : x/2;
-    ty = center_it ? 0 : y/2;
-    tz = center_it ? z/2 : z;
-
-    translate([tx, ty, tz - label_depth])
-        rotate([0, 0, rotate_text ? 90 : 0])
-            linear_extrude(height=label_depth + 0.02)
-                text(
-                    txt,
-                    size=final_size,
-                    font=label_font,
-                    halign="center",
-                    valign="center"
-                );
-}
-module place_top_labelOLD(txt, x, y, z, center_it=false) {
     tx = center_it ? 0 : x/2;
     ty = center_it ? 0 : y/2;
     tz = center_it ? z/2 : z;

openscad/stress_test_models.scad~

@@ -0,0 +1,166 @@
+#!/usr/bin/openscad -o /tmp/ignore.stl
+//
+// stress_test_models.scad
+// 20260317 ChatGPT
+// $Id$
+// $HeadURL$
+//
+// Example command lines:
+//
+//   openscad -D 'model="cube"'  -o cube_20260317_1335.stl  stress_test_models.scad
+//   openscad -D 'model="ybar"'  -o ybar_20260317_1335.stl  stress_test_models.scad
+//   openscad -D 'model="tower"' -o tower_20260317_1335.stl stress_test_models.scad
+//   openscad -D 'model="all"'   -o all_20260317_1335.stl   stress_test_models.scad
+//
+// Suggested slicer use:
+//
+//   1) Print each model as a SEPARATE run.
+//   2) For ybar, orient the LONG dimension along the printer's Y axis
+//      so the bed moves the long way front-to-back.
+//   3) Infill is set in Orca Slicer, not here.
+//
+// Suggested slicer settings:
+//
+//   cube:  0.20 layer, 3 perimeters, 20-25% grid or gyroid
+//   ybar:  0.20 layer, 3 perimeters, 15-25% grid
+//   tower: 0.20 layer, 3 perimeters, 0-10% infill, no brim at first;
+//          add brim only if adhesion becomes the issue rather than motion
+//
+
+/* [General] */
+model = "all";              // [cube,ybar,tower,all]
+center_models = false;      // true / false
+add_labels = true;          // true / false
+
+/* [Cube Dimensions] */
+cube_x = 40;
+cube_y = 40;
+cube_z = 40;
+
+/* [Y Bar Dimensions] */
+ybar_x = 20;
+ybar_y = 150;
+ybar_z = 50;
+
+/* [Tower Dimensions] */
+tower_x = 18;
+tower_y = 18;
+tower_z = 120;
+
+/* [Edge Treatment] */
+corner_radius = 1.2;        // 0 for sharp corners
+$fn = 48;
+
+/* [Labeling] */
+label_depth = 0.6;
+label_size  = 7;
+label_font  = "Liberation Sans:style=Bold";
+
+/* [Layout For model="all"] */
+gap_between_models = 20;
+
+
+// --------------------------------------------------
+// Main
+// --------------------------------------------------
+
+if (model == "cube") {
+    make_cube();
+}
+else if (model == "ybar") {
+    make_ybar();
+}
+else if (model == "tower") {
+    make_tower();
+}
+else if (model == "all") {
+    make_all();
+}
+else {
+    echo("ERROR: model must be one of: cube, ybar, tower, all");
+}
+
+
+// --------------------------------------------------
+// Assemblies
+// --------------------------------------------------
+
+module make_all() {
+    x0 = 0;
+    x1 = x0 + cube_x + gap_between_models;
+    x2 = x1 + ybar_x + gap_between_models;
+
+    translate([x0, 0, 0]) make_cube();
+    translate([x1, 0, 0]) make_ybar();
+    translate([x2, 0, 0]) make_tower();
+}
+
+
+module make_cube() {
+    difference() {
+        rounded_box(cube_x, cube_y, cube_z, corner_radius, center_models);
+        if (add_labels)
+            place_top_label("CUBE", cube_x, cube_y, cube_z, center_models);
+    }
+}
+
+
+module make_ybar() {
+    difference() {
+        rounded_box(ybar_x, ybar_y, ybar_z, corner_radius, center_models);
+        if (add_labels)
+            place_top_label("YBAR", ybar_x, ybar_y, ybar_z, center_models);
+    }
+}
+
+
+module make_tower() {
+    difference() {
+        rounded_box(tower_x, tower_y, tower_z, corner_radius, center_models);
+        if (add_labels)
+            place_top_label("TOWER", tower_x, tower_y, tower_z, center_models);
+    }
+}
+
+
+// --------------------------------------------------
+// Geometry helpers
+// --------------------------------------------------
+
+module rounded_box(x, y, z, r=0, center_it=false) {
+    if (r <= 0) {
+        cube([x, y, z], center=center_it);
+    } else {
+        if (center_it) {
+            translate([-x/2, -y/2, -z/2])
+                rounded_box_uncentered(x, y, z, r);
+        } else {
+            rounded_box_uncentered(x, y, z, r);
+        }
+    }
+}
+
+
+module rounded_box_uncentered(x, y, z, r) {
+    linear_extrude(height=z)
+        offset(r=r)
+            offset(delta=-r)
+                square([x, y], center=false);
+}
+
+
+module place_top_label(txt, x, y, z, center_it=false) {
+    tx = center_it ? 0 : x/2;
+    ty = center_it ? 0 : y/2;
+    tz = center_it ? z/2 : z;
+
+    translate([tx, ty, tz - label_depth])
+        linear_extrude(height=label_depth + 0.02)
+            text(
+                txt,
+                size=label_size,
+                font=label_font,
+                halign="center",
+                valign="center"
+            );
+}

orca-slicer/settings/PolyLite PLA @System - Z-Tower.info

@@ -1,5 +0,0 @@
-sync_info = create
-user_id = 
-setting_id = 
-base_id = OGFSL19
-updated_time = 0

orca-slicer/settings/PolyLite PLA @System - Z-Tower.json

@@ -1,16 +0,0 @@
-{
-    "compatible_printers": [
-        "Sovol SV06 ACE 0.4 nozzle"
-    ],
-    "fan_cooling_layer_time": [
-        "20"
-    ],
-    "filament_settings_id": [
-        "PolyLite PLA @System - Z-Tower"
-    ],
-    "from": "User",
-    "inherits": "PolyLite PLA @System",
-    "is_custom_defined": "0",
-    "name": "PolyLite PLA @System - Z-Tower",
-    "version": "2.3.0.3"
-}

orca-slicer/settings/Y-bar_20260317_final.info

@@ -1,5 +0,0 @@
-sync_info = update
-user_id = 
-setting_id = 
-base_id = GP004
-updated_time = 0

orca-slicer/settings/Y-bar_20260317_final.json

@@ -1,24 +0,0 @@
-{
-    "bottom_shell_layers": "5",
-    "brim_type": "outer_only",
-    "from": "User",
-    "inherits": "0.20mm Standard @Sovol SV06 ACE",
-    "initial_layer_line_width": "0.42",
-    "initial_layer_print_height": "0.2",
-    "inner_wall_speed": "80",
-    "is_custom_defined": "0",
-    "line_width": "0.42",
-    "name": "Y-bar_20260317_final",
-    "only_one_wall_top": "0",
-    "outer_wall_acceleration": "1500",
-    "outer_wall_line_width": "0.42",
-    "outer_wall_speed": "60",
-    "print_settings_id": "Y-bar_20260317_final",
-    "skirt_loops": "2",
-    "sparse_infill_density": "20%",
-    "sparse_infill_pattern": "gyroid",
-    "top_shell_layers": "5",
-    "top_solid_infill_flow_ratio": "1",
-    "version": "2.3.0.3",
-    "wall_loops": "3"
-}

orca-slicer/settings/Z-tower_20260317_final.info

@@ -1,5 +0,0 @@
-sync_info = update
-user_id = 
-setting_id = 
-base_id = GP004
-updated_time = 0

orca-slicer/settings/Z-tower_20260317_final.json

@@ -1,26 +0,0 @@
-{
-    "bottom_shell_layers": "5",
-    "brim_type": "outer_only",
-    "from": "User",
-    "inherits": "0.20mm Standard @Sovol SV06 ACE",
-    "initial_layer_line_width": "0.42",
-    "initial_layer_print_height": "0.2",
-    "inner_wall_speed": "80",
-    "is_custom_defined": "0",
-    "line_width": "0.42",
-    "name": "Z-tower_20260317_final",
-    "notes": "Orca serialization note\n\nIn Orca Slicer 2.3.0.3, some live profile values may not appear in the saved process JSON even when they are active in the UI. For the Z-tower profile, Sparse infill density was verified in the live UI as 10% before slicing, even though the saved JSON did not include a sparse_infill_density key.\n\nScreenshot was taken showing the 10% value, 20260318_184351_Wed.png",
-    "only_one_wall_top": "0",
-    "outer_wall_acceleration": "1500",
-    "outer_wall_line_width": "0.42",
-    "outer_wall_speed": "40",
-    "print_settings_id": "Z-tower_20260317_final",
-    "seam_gap": "0",
-    "seam_position": "back",
-    "skirt_loops": "2",
-    "sparse_infill_pattern": "line",
-    "top_shell_layers": "5",
-    "top_solid_infill_flow_ratio": "1",
-    "version": "2.3.0.3",
-    "wall_loops": "3"
-}

orca-slicer/settings/cube_20260317_final.info

@@ -1,5 +0,0 @@
-sync_info = create
-user_id = 
-setting_id = 
-base_id = GP004
-updated_time = 0

orca-slicer/settings/cube_20260317_final.json

@@ -1,23 +0,0 @@
-{
-    "bottom_shell_layers": "5",
-    "brim_type": "no_brim",
-    "from": "User",
-    "inherits": "0.20mm Standard @Sovol SV06 ACE",
-    "initial_layer_line_width": "0.42",
-    "initial_layer_print_height": "0.2",
-    "inner_wall_speed": "80",
-    "is_custom_defined": "0",
-    "line_width": "0.42",
-    "name": "cube_20260317_final",
-    "only_one_wall_top": "0",
-    "outer_wall_acceleration": "1500",
-    "outer_wall_line_width": "0.42",
-    "outer_wall_speed": "60",
-    "print_settings_id": "cube_20260317_final",
-    "seam_position": "back",
-    "skirt_loops": "2",
-    "sparse_infill_pattern": "grid",
-    "top_shell_layers": "5",
-    "top_solid_infill_flow_ratio": "1",
-    "version": "2.3.0.3"
-}