piston ring compression aid specifically for 45mm pistons (on chinese 52cc--58cc chainsaws)

printed two of them just for redundancy as i was not sure if they hold up but they held up well; you will need barely any pressure to compress the rings you may need to flex the compression aid outwards a bit for getting them onto the piston but that is ok just do not over do it.

printed mine in PLA 

advise to print completely solid ie 100% infill or with as many walls as possible for maximum mechanical strength