Choose your stage

Each calculator uses the engineering formulas and capacity tables from the official APEX workbook for that model.

How it works

Loads are vertical, in pounds.

1. Pick the stageSelect the model above. The calculator opens below with that stage’s plan.
2. Enter your loadsClick the grid point where each motor or point hangs and type its weight. Tab, Enter and the arrow keys move between cells.
3. Read the colorsTotals for every structural member update instantly and change color as they approach capacity.
4. Save or printSave the plan as a file to reopen later, or print it / save it as a PDF to send to the APEX team.

• Under 90% of capacity — approved
• Over 90% — engineer review required
• Over 100% — not approved
• 4240: ¼, ⅓ or ½ point overload

Prefer Excel?

Download the original APEX workbooks. They require desktop Microsoft Excel with macros enabled — see the setup instructions.