Chassis supports – 2nd measurement

I made a couple of additional measurements motivated by a reader’s comment. Last time in “Chassis supports and door bars – project ready” I used car’s own weight to bend the front and rear downwards. This time I put weight on the door sill and measured the bending that way.

Here are the results:

Weight 70 kg, without door bar. Left: 0,35 mm. Right 0,35 mm.

Weight 70 kg, with door bar: Left: 0,27 mm. Right 0,27 mm.

Weight 100 kg, without door bar. Left: 0,51 mm. Right 0,49 mm.

Weight 100 kg, with door bar: Left: 0,39 mm. Right 0,40 mm.

Conclusion is that door bars reduce bending 18-23 % when measured with 70-100 kg weight. Sounds nice, doesn’t it!

Seriously, deflection with 100 kg is less than half millimeter measured from the height of windscreen frame. Bars seem to work and they give some extra stiffness to old car’s chassis.