Isometric drafting technique — using a bounding box for layout In setting up an isometric drawing, the “bounding box” method helps the drafter do what before adding detailed geometry?

Introduction / Context:
A practical way to begin an isometric drawing is to rough out a containing volume that represents the overall length, width, and height. This “bounding box” approach frames the maximum extents so the subsequent features align and fit within intended limits, avoiding scale creep and misalignment.

Given Data / Assumptions:

• The drafter is preparing an isometric view of an object with known overall dimensions.
• A preliminary box in isometric is created to establish limits.
• Detail features (holes, chamfers, fillets) will be added later within these extents.

Concept / Approach:
By constructing an isometric bounding box using the three isometric directions (two at 30 degrees and one vertical), the drafter defines a clear, measurable workspace. This helps ensure the entire part fits on the sheet and keeps features proportionate. It also provides reference edges for offsets, polar tracking, and isocircle placement.

Step-by-Step Solution:

Verification / Alternative check:
Compare an isometric created with and without a bounding box. The version without often suffers from inconsistent extents, while the bounded version keeps dimensions organized and reduces rework.

Why Other Options Are Wrong:

• Determining “vertical and horizontal” lines: isometric has two 30-degree axes and a vertical; “horizontal” is not used in the same way.
• Positioning in paper space: that is a layout/sheet task, not a modeling strategy.
• None/auto-dimension: bounding boxes do not dimension objects automatically.

Common Pitfalls:

• Skipping the bounding box and discovering too late that the part does not fit the title block area.

Final Answer:
confine the isometric drawing to its maximum size