Hi
I'm in the process of replacing my sierras sills with shs 90x90
I was planning on using 2-3mm thickness
Today I contacted just about all the steel suppliers in Adelaide seems 3.5mm is the thinnest I can get.
After a lot of research I have found people use different sizes, some use 100x100x3
If I do go the way of the 3.5mm will the weight (about 10kg per sill) be too much for the thin panels it's going to be welded too and will this cause issues?

Thanks for the help in advance
Cheers
Simon