Seems like a case of trying to reinvent the wheel to me. To be honest I buy my oil in a 20l container and decant it into a measuring jug as I need it. It's a bigger outlay but works out a fair bit cheaper in the long run. I do the same with wd40, 5L bottle for £19.99 rather than £1.99 per 100m can, basically works out you get 4l free .