Before I start please excuse my dodgy paint skills and this post was bit of a rush…
Goal is to fit multistar 4000mAh 3S 11.1v battery. These batteries have a decent capacity with minimal weight and dimension gain.
This is the standard battery bay. If you look where I marked the yellow line the body has 2 layers of polystyrene. Its important to leave the bottom layer intact as cutting down to label depth takes you very close to bursting through.
This was my first attempt and removed the step which I later glued back on.
I have marked where I made my cuts, measuring width of battery and using that as datum. Cut a straight line so cut out is parallel. You do not want to follow profile of cover. Just cut as deep as step in polystyrerene and that section should come out in one piece.
I used a razor blade but Stanley blade would probably be better
You will find that because the cables on battery make one edge not straight you might want to make the extra cuts on the side without motor cable. You may expose a cavity for cables but as long as you are not cutting to the profile of lid you will not hit them.
Take it nice and easy, you can always take more off but cant but it back on. A tight fit is preferable.
You can add a strip of insulating tape to tidy things up.
Battery now fits great.
But you will find cover does not sit flush.
Make a few cuts to the cover, one side longer than other to accommodate cables.
Charged on the stock disco charger no problem at all.
Will update on first flight.