6061 or 6082 or 7020

[broesel33]

which aluminium must I use?
and why.
A friend sayed I must use 7020....

thanks

[vito.a]

I guess no one has answered this.
Need to know what you are using it for?
Just guessing you are using it for the chassis and you want to weld on it, then 6061 T-6 would be best. You will loose the T-6 hardening when you weld, but if you TIG weld it and are careful with the amount of heat it will be OK.