1.6mm, its an easy one to remember :o)

Martyn

British standard wire gauge + or - 0.1mm

1mm - 20gauge
1.2mm - 18gauge
1.6mm - 16gauge
2mm - 14gauge
2.5mm - 12gauge
3mm- 10gauge

Because all are not created equal :D
In my case I used 1.6mm steel plate welded (spaced) to the frame for the simple reason with my weight of 135kg I would step right through that flimsy ally floor and pull all the rivets out whilst at it....:o

my car is 1.6mm ali floor 5025 grade so its nice and tough. its bonded on along with 3.2mm sealed rivets 2.5inch apart. the car has been on the road for 2 years now and taken lots of track abuse, there isnt a single lose rivet. if you run over something bad enough to pierce through the floor it wont matter if its ali or steel, its still coming to get ya. the seat is the most important thing. my tritons are 2-3inch thick on the bottom.

Truth is the rivets job is secondary if using bonding agent because that stuff alone is strong enough for the job. I have tried to seperate two pieces of ali that were bonded with some gook and the ali tore before the sealer let go. I had to heat them up to get them to part company. So rivets and bonding has got to be the way to go me thinks.

Bob