Trim Angle iron Frame one corner works not so lucky with the rest

Hi i am a autocad C3D 100% and some inventor type 50 % now 10% solidworks

trimed one leg with success canot trim other 3 most like my work flow

any tips on how to trim effficiently the practise frame please review attached

thanks in advance will dig thru you tube and vid here for triming pointers

Regards Pete

Edu ​​​​​​​