80×40 or 40×40 profile for your sim rig?

The most common question we get at SimSlot is whether a rig should use 40×40 or 80×40 profile. The answer comes from stiffness and weight.

Stiffness

Our 40×40 Light profile has a moment of inertia of 9.26 cm⁴ in both directions. The 80×40 Light profile has 70.91 cm⁴ about its strong axis. Loaded on its tall side, the 80×40 is about 7.7 times stiffer than the 40×40.

Weight

The 80×40 Light weighs 3.09 kg per metre against 1.775 kg per metre for the 40×40 Light, which is about 1.7 times more material for 7.7 times the stiffness. The 40×40 Heavy section weighs 2.47 kg/m and has 14.24 cm⁴, so it stiffens in every direction but gives less than the 80×40 when loaded on its tall side.

Which should you use?

• 80×40: main rails, wheelbase and pedal decks, seat supports and any long unsupported span.
• 40×40: short cross members, monitor stands, shifter and handbrake mounts, cable management.
• Mixed: most rigs use 80×40 for the base and 40×40 for the rest. All sections share the 8 mm slot, so the same T-nuts, brackets and end caps fit.

Check before you cut

Use the 3D and CAD downloads on each product page to check the section in your own design. Threaded ends and drilled holes can be added when you order.