Stacked column chart, but with one stack on a second axis?

Hi there, tearing my hair out at the moment. Trying to make a stacked column chart that will have say, 3 stacks (of which each stack has 4 data points) of data on the primary axis, then another stack of 4 data points linking to the secondary axis. The second axis will have a much larger scale than the first so it's necessary to separate.

Thanks! Although that isn't quite what I wanted (probably down to my description). I managed to figure it out in the end and came up with something like this (ignore the fact it looks ugly and needs a bit of fine tuning):