Best-Practice Modeling Workflows#

Overview#

This page ties the section together into a routine. It is opinionated; adapt it to your team. The phases:

1. Plan and define inputs.
2. Set up the file.
3. Build skeleton and base.
4. Add detail in a sensible order.
5. Stress-test.
6. Document and organize.
7. Variants, derived designs, hand-off.

Where to find it#

All of this uses tools covered in this section: Change Parameters, timeline, groups, configurations, derive, plus Save with version notes in the data panel.

Step by step#

Phase 1: plan#

1. Write down what the part must do: envelope, mating parts, manufacturing method.
2. List the inputs likely to change: sizes, counts, fits, material thickness.
3. Sketch on paper if helpful: where are the datums, what is symmetric?
4. Decide: single part, multi-body, or assembly? Parametric history or direct edits? (For your own parts: parametric.)

Phase 2: set up#

1. New design; save it right away with a meaningful name in the right project.
2. Check document units (Browser > Document Settings).
3. Confirm the design is in Parametric Modeling Mode (the timeline is visible; if it is not, right-click the default component in the Browser and choose Change to Parametric Modeling Mode).
4. Open Change Parameters and enter your inputs as user parameters with comments. Include tolerance/clearance parameters.
5. Create components for separate parts early (right-click > New Component) so geometry lands in the right place. Check which component is active (its browser entry is highlighted) before sketching, because new sketches and features land in the active component.

Phase 3: skeleton and base#

1. Optional layout sketch with centerlines and key points, anchored to the origin.
2. Base sketch constrained and dimensioned using parameters.
3. First extrude. Rename entries as you go.
4. Add datum planes as needed (offset from origin planes).

Phase 4: add detail in order#

1. Major cuts and holes.
2. Bosses, ribs and internal features.
3. Patterns/mirrors.
4. Shell if applicable. Think about order: shelling before adding bosses affects whether bosses are solid or hollow.
5. Fillets and chamfers last, selected by face or tangent chain.
6. Group the timeline by phase and name the groups.

Phase 5: stress-test#

1. Change each input to extremes and watch for errors.
2. Check for interference and thin walls using Inspect tools (Section Analysis, Measure, Interference); see the Inspect section of the guide.
3. Verify mass properties or other checks if relevant (Properties on body/component).
4. Fix fragilities now. Add limiting expressions (max, min, or if) where legitimate. In expressions, separate function arguments with a semicolon, for example max(wall; 1.2 mm); Autodesk's help advises against the comma because it clashes with the decimal separator in some locales.

Phase 6: document#

1. Add comments in the Change Parameters table.
2. Rename remaining generic items.
3. Collapse groups. Make sure the timeline marker is at the end.
4. Add a descriptive version note when saving ("v3: added mounting slots, parametrized wall").
5. Set physical materials and appearances.

Phase 7: variants and hand-off#

1. For size or option families, create a configuration table.
2. For downstream work (fixtures, CAM, drawings), consider Derive or insert as an external component.
3. Before sharing, remove dead sketches, ensure no red icons, and compute all.
4. Export formats (STEP, STL, DXF) as needed for downstream users; export from the right configuration.

Options reference#

Tips and pitfalls#

Tip: Save versions at milestones (after base, after details, before big changes). Version history is your real undo across sessions.

Tip: Build one thing at a time and check for red icons after each. Debugging a single new feature is easy; debugging twenty is not.

Tip: Be willing to rebuild a bad foundation. A clean 15-minute rebuild beats hours of patches.

Warning: Do not model with overlapping, non-intent features "just to see" in a file you'll deliver. Use a scratch file.

Warning: Avoid copying geometry from other designs by paste when a link (derive, insert) or shared parameter would work; copies drift.

Warning: Large single-file assemblies with long timelines get slow. Split into parts and use components and external references.

Workflow variants:

• Quick prototype: skip configurations and derive; keep parameters for major dimensions only.
• 3D printing: add tol and layer-related parameters; check minimum wall; export STL per part.
• Machining: parameterize stock size, tool radii (inside corner fillets), hole standards.
• Sheet metal: rely on sheet metal rules and configure thickness through rules.
• Imported parts: turn history off or use direct edits; do not try to impose parametrics.

Review checklist#

• Units correct; document units match manufacturing.
• All key dimensions are user parameters with comments.
• Sketches fully constrained and origin-anchored.
• No red or yellow timeline icons.
• Timeline marker at the end; entries renamed and grouped.
• Fillets and chamfers late in history.
• Stress-tested at extremes.
• Saved with a version note.
• Variants in a configuration table if needed.

Worked example: planning an enclosure with numbers#

Suppose the board is 60 x 40 x 1.6 mm with components up to 12 mm tall on top and 3 mm of solder pins underneath.

Inputs (user parameters).

Derived values. Inside length is pcb_l + 2 * clr = 61 mm, outside length 61 + 2 x 2 = 65 mm; inside width 41 mm, outside 45 mm. Inside height is stand_h + pcb_t + top_clr = 19.6 mm, so outside height with a 2 mm floor and a separate 2 mm lid is 21.6 mm. Write these as expressions rather than numbers, and you can change pcb_l to 100 mm and watch the whole box follow.

Extremes to test. Lower and upper bounds should come from real boards: 40 x 30 and 120 x 80 mm. At 40 x 30 the boss diameter of 6.25 mm and the bolt pattern must not overlap the board's mounting holes; at 120 x 80 a 2 mm wall might flex, so consider adding ribs.

Timeline order and why#

A robust order is: datum planes, base body, shell, lid lip, bosses, holes, patterns, fillets, chamfers. Two ordering rules come up often.

• Shell before bosses if bosses should stay solid. If you shell after adding bosses, the bosses hollow out unless you pick faces carefully.
• Fillets before shell if you want inside corners rounded automatically: outside radius r and wall t give an inside radius r - t, so a 3 mm outside radius with 2 mm wall leaves a 1 mm inside radius. In a parametric model write the outside radius as wall + inner_r to keep the inside radius constant when the wall changes.

When you need a feature to appear earlier than the end of the timeline, roll the marker back and insert it rather than redrawing. See Rollback and editing features.

Save, version and hand-off discipline#

• Save after every phase and add a short note: "v2 base and shell done, parameters tested to 120 x 80". Notes are the only record of why a change was made.
• Never hand off with the marker rolled back, with suppressed features you forgot about, or with unnamed sketches. A reviewer looking at "Sketch47" learns nothing.
• Hide construction planes, sketches and helper bodies before exporting; export the specific component or body, not the whole design, when you only need one part.
• Run through the review checklist below, then test the design from scratch by opening the version in a fresh session and changing one parameter. If it recomputes, a colleague can do the same.

Matching the workflow to the job#

Failure modes and fixes#

Practice exercise#

Design the parametric enclosure above and prove it adapts.

1. Create parameters: pcb_l=60, pcb_w=40, pcb_t=1.6, clr=0.5, wall=2, stand_h=4, top_clr=14, screw_d=2.5 (all mm) and the derived ones boss_od = screw_d * 2.5, in_l = pcb_l + 2 * clr, in_h = stand_h + pcb_t + top_clr. Add a comment to every parameter.
2. Create components Base, Lid and Fasteners. Build the base from an origin-anchored sketch, extrude in_h + wall, shell with wall, add four bosses 4 mm inside each corner, add holes of screw_d with the Hole tool, and fillet last.
3. Group the timeline into Base, Bosses, Fillets and rename every entry. Save a version with a note.
4. Stress test by setting the board to 40 x 30, then 120 x 80, then 100 x 100. Record any error, find the first failing feature, and fix it with a limiting expression such as max(boss_od; screw_d + 2 * wall).
5. Verify the interior with Section Analysis at each extreme and measure the wall thickness.
6. Build a three-row configuration table (Small, Default, Large) and a derived laser-cut template of the lid (Derive the Lid component into a new design).
7. Write the review checklist result in the version note.

Expected result: a documented enclosure that adapts to boards from 40 x 30 to 120 x 80 mm by editing a handful of numbers, with a recorded list of limits you discovered.

Related#

• Design-for-change patterns
• Configurations
• Derive