anyone out there doing a phd that is heavy on lab work? mine is biochemistry. I'm third year and haven't started writing at all so a bit worried! I have got caught up with so many technical errors, instrumentation troubles etc. I don't get much supervision so I am trying to start my thesis writing whilst doing more lab work to try to make a complete story as I don't have enough results yet! I look back at things I've done and realise I should have done more controls, replicates etc and trying to fill the gaps.

Its a time management issue which is not limited to lab based work. I am doing a computational based PhD and I have the same issue. There is always another calculation to do. It is particularly tough if you are not getting results because you cant relax reading papers when you are worrying about having no results. The problem of having to write your thesis wont go away though so you need to learn to time manage.

I don't think it's necessarily about time management - there's not much point in spending time writing a thesis when you don't have many results!

But, now that you are in your third year, you need to see exactly what you need to do to finish your thesis and make sure you work towards your deadline.

Repeat things if you can or if you really need more replicates, but you can always just say in your thesis that you recognise that you should have done this or that.

6 months for writing up is fine if you have only writing to focus on. If you will still need to do lab work, or you will working part-time, then you will need a longer writing up time. I would say once you have a thesis plan, get the lab work done before starting serious writing.