Neutering and weight!

Hello everybody! Awhile ago I was looking into neutering my male chinchillas and I swear I came across a thread that said how much a chinchilla should weigh before they're neutered but I can't seem to find it. Do you guys know how much they're supposed to weigh?
Also I was hoping I could find approximate healthy weights for chinchillas at different age marks. If you know either of things your input would be greatly appreciated!