ive resorted to lifting up my mom's sewing machine (its a singer ), its in a case with a hgandle on top and it's pretty heavy, i can barely lift it 4 times in a row and i can't curl it (yet! )
if i use my other hand to 'guide' my other hand i can do a curl, and it feels like its working my arm really good!
im not sure how much it weighs and i don't want to hurt myself so im risking e-humiliation by posting for advice here....

will lifting it beside my body, bending my arms while doing it be dangerous?
ive never seen anybody lift like that....

i dunno how to reall explain it though, i just have it on a chair and lift it until i cant lift anymore!
i feel like a caveman so i need to know if this is a good technique?