Finish previous work during current position I will soon change of lab, moving from a PhD student position to post-doc position. During the last months of my contract as a PhD student, I tried to finish everything I started but I still have a few projects in progress. These projects include collaborative paper with other groups, so I am not the only one involved.

I was wondering what was the general agreement when changing position with unfinished project.  I see three main possibilities here:


At the beginning of the new contract, I spend all my time finishing the previous project so I do not have to worry about them for too long (but I do not start right away to work for my new boss)
I spend one day per week (for instance) working for the past project and the rest for the current one
I do not work at all on the previous project during office hours, but rather after work and during the week-end (which I would prefer not to do)


I have to precise that my future boss is not involved in the project I would need to finish. I also plan to ask him the question directly when I start the new position, but I thought a little background about what is commonly done could be beneficial before starting this discussion.

NB: this question is different from this one since it does not concern the ownership of the research, but rather on how to spend the time in the lab.
As an academic working with a couple of post-docs, my rule is you can do what you want with your time as long as you do what is required for the project that employs you. 
It is also the case that I know (and indeed expect) that post-docs will have work of their own that they'll want to finish up or extend.

I would not be happy with option 1, but option 2 would be good for me. Weekends are your own. If you spend them writing more papers, I will not object. But please do have some rest and relaxation time.

As a post-doc, you are starting to build your own career, so writing independent papers, and thereby forging your own way,  is a good thing. But there are a lot of benefits to be had from integrating yourself in your new working environment, and working too much on your own stuff means that you will miss that opportunity (and possibly make a bad impression).