Basically, when the shell is made, the whole process of injection moulding puts lots of stress on the shell, which is "set" in the frame due to the rapid production process. The molten plastic is squirted into the shell mould, cooled rapidly, then churned out of the mould. This leaves the plastic molecules stressed, and liable to splinter or crack during collisions or excessive twisting etc.
The below process is basically reassembling the plastic molecules without harming the frame shape, in order to stress-relieve the plastic.
I have successfully done the below process on my P4A shell, with no adverse effects and no more cracks. I used to do this process years ago on RC car parts, and it used to make a huge difference to the failure rate.
1. Strip everything out of your bird, ie anything electronic, that is located within the shell. Be prepared that you will almost certainly lose any stickers on the shell, and void your warranty, so it really is your choice to do this or not. Take your time, and take photos as you go to ensure you reassemble correctly. Only attempt if you are 100% sure what you are doing and the consequences of getting it wrong.
2. Put the shell in a large metal watertight cooking container that allows the entire frame to fit and has the depth to allow water to cover the shell. Only do one half of the shell at a time.
3. Pour in boiling water into the container to completely submerge the shell. This is easier said than done, as chances are you will need a couple of kettles in order to submerge the shell. I partially filled the container with boiling water, then topped up with hot tap water, and put on top of the cooker on a low flame to bring the whole container up to boiling point. Do not use a large flame as the direct heat in the area where the flame is may warp or melt the shell if it is in contact with the metal container.
4. Leave to cool naturally to room temperature (a good 90 minutes). This is the most important part!!! Do not pour in cold water etc or anything to speed up the process, the cooling down process and the time it takes naturally is what 'fixes' the stressed plastic.
5. Reassemble, and be stress free!
The below process is basically reassembling the plastic molecules without harming the frame shape, in order to stress-relieve the plastic.
I have successfully done the below process on my P4A shell, with no adverse effects and no more cracks. I used to do this process years ago on RC car parts, and it used to make a huge difference to the failure rate.
1. Strip everything out of your bird, ie anything electronic, that is located within the shell. Be prepared that you will almost certainly lose any stickers on the shell, and void your warranty, so it really is your choice to do this or not. Take your time, and take photos as you go to ensure you reassemble correctly. Only attempt if you are 100% sure what you are doing and the consequences of getting it wrong.
2. Put the shell in a large metal watertight cooking container that allows the entire frame to fit and has the depth to allow water to cover the shell. Only do one half of the shell at a time.
3. Pour in boiling water into the container to completely submerge the shell. This is easier said than done, as chances are you will need a couple of kettles in order to submerge the shell. I partially filled the container with boiling water, then topped up with hot tap water, and put on top of the cooker on a low flame to bring the whole container up to boiling point. Do not use a large flame as the direct heat in the area where the flame is may warp or melt the shell if it is in contact with the metal container.
4. Leave to cool naturally to room temperature (a good 90 minutes). This is the most important part!!! Do not pour in cold water etc or anything to speed up the process, the cooling down process and the time it takes naturally is what 'fixes' the stressed plastic.
5. Reassemble, and be stress free!