My PhD is linked to a larger project to which I work as a data collector/research assistant. We are a team of 5 (4 work on the larger project part time and I'm doing my PhD). When I started my PhD my supervisor clarified that I would data collect for the larger project and they would help me part time. Recently, I have been working a lot more than is required for my PhD data collection. Is there anything I can do, rather than take it or leave it? I have tried to negotiate extra pay but was not successful. Is this common? I realise with PhDs, because it is study, terms and conditions of the job are not written down.
Many thanks.