Joe's 1000x600x200 steel and aluminium router started

[Voicecoil]

Aluminium Rect section doesn't compare to HD profile in terms of resonance and vibration dampening and this is should be more of a concern than twisting deflection you seem to be chasing if you want a good Router.

That's an interesting point and worthy of investigation. I've saved the impulse response files from a length of the 6 x 3 x 3/8 box, does anyone have a short-ish (~600mm) length of 160 x 80 profile they can lend me to do a comparative measurement?