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Lego Mechanical Drawing

Before anyone touches Fusion, we're going to build something out of Lego and draw it with a pencil. Every 3D model you'll make this year starts as a flat 2D sketch, and today's job is to train your eye to see a solid object as a set of flat views. No computers. This is real.

Overview

You'll build a small Lego creation, then draw it the way engineers draw parts: three straight-on orthographic views (top, front, and side) and one isometric view, on a printed drawing template. The idea, not the technique, is the point. Next week Fusion draws the perfect lines for you, but it will still ask you to think in 2D sketches first.

Materials

  • One Lego build plate
  • Six standard Lego bricks, any sizes
  • One printed drawing template (I'll hand these out)
  • A pencil, and an eraser you're not embarrassed to use

You've got it when…

  • Your template has a top, front, and side view of your build, lined up with each other and drawn to the grid at true size.
  • The isometric panel shows the same build on the triangular grid.
  • The title block is filled in with your name, the scale, and the grid size.
  • Someone who has never seen your build could rebuild it from the sheet alone.

Collaboration & AI

Work: In pairs at your table for the building and the discussion; each of you draws your own build on your own sheet.

AI — AIAS Level 1, No AI: Pencil, paper, and plastic bricks. There isn't a lot for AI to do here. What the levels mean.

Build Something

Ten minutes, and the specifics don't matter. The build is raw material for the next part.

  1. Pick one build plate and six standard bricks from the bin. Any sizes, any colors. Six bricks; I count.

  2. Build something simple on the plate. A tower, a bridge, a staircase, a piece of sculpture; anything you like, as long as it uses all six.

    Keep it square

    Stack the bricks flat, studs up, the way the box intended. No bricks on their sides, wedged in at an angle, or balanced on one stud. Clever connections are fun to build and miserable to draw, and you're about to draw this.

  3. When you're done, leave the build on the plate in front of you and take a photo of it for your notebook. Don't take it apart.

Draw It

You'll get the template after the slides. Everything below matches the labels printed on it.

  1. Fill in the title block: your name under Drawn By, the scale, and the grid size. The square grid is 2 mm; the brick dimensions printed on the sheet tell you how many squares each brick takes. Use the same scale in every view.

    Count squares, don't measure

    A stud pitch is 8 mm, which is four grid squares. A brick is 9.6 mm tall, which is nearly five. Count squares for every edge and your views will line up on their own.

  2. Draw the front view first: the build seen straight on from the side you decide is the front, with no depth and no angles, every edge at its true length. Mark the plate's edge along the bottom.

  3. Draw the top view directly above the front view, looking down. Its width must match the front view exactly; that's why it sits above it. Include the studs as small circles on the visible tops.

  4. Draw the side view to the right of the front view, looking from the right. Its height must match the front view. This is the view students most often skip; it's also the one that tells a builder how deep everything is.

    Why the views line up

    Engineers arrange the views this way on purpose. Top above front shares the width; side beside front shares the height. Lay a ruler across the sheet and the edges should meet. If they don't, one view is wrong, and the layout just told you which measurement to check.

  5. Draw the isometric view on the triangular grid: one corner of the build toward you, vertical edges vertical, and the other two directions following the grid's diagonals. Every edge stays parallel and to scale, which is what makes isometric a drawing you can measure and perspective a drawing you can't.

  6. Check the sheet against the build: count the studs in each view, confirm the widths and heights agree across views, then put your pencil down. Stop here; there's a part two, and I'll tell you when.

Turn It In

  • Your completed drawing template, on paper, handed to me at the end of class.
  • A notebook entry titled Lego Mechanical Drawing with the photo of your build and a photo of your finished sheet.
  • In the same entry, two or three sentences written at the end of class on what worked and what you'd draw differently. I'll tell you what to reflect on once part two is over.

How It's Graded

This lab is worth up to 4 points. One score covers everything you turn in.

Score What it looks like
4 — Excellent Top, front, and side views drawn to the grid at true size and aligned with each other (widths agree between top and front, heights between front and side), studs shown, an isometric view on the triangular grid with parallel edges, the title block filled in, and a notebook entry with both photos and the reflection. Someone could build it from the sheet.
3 — Above Average All four views present and mostly to scale, with a slip: a side view a square off, an isometric with a wandering edge, or a missing title block entry.
2 — Average A view missing, or views that don't agree with each other, or a drawing from an angle where an orthographic view belongs. The row for the build that was too clever to draw.
1 — Below Average One or two views sketched freehand, off the grid, or a sheet with no notebook entry behind it.
0 — Failing No sheet handed in and nothing in the notebook.