I am using a lot of soft aluminum on a F4F rudder and h stab. (non airworthy aircraft) I would like to know if someone has references they can point me to, or experience in, heat treating to a Type 3 or so. The web has provided some info but it seems to be all over the map. So, if you have made a skin from soft material and thrown it in the over for 3 hours at 175 and then let it air cool please let me know the specifics. Thanks.