Why to use the nut on the extruder barrel

Just to remind me to writew a small section explaining why a nut is essential.

For those curious for now until a few hours later today till i write it, this is wehat that 4p nut on the brass barrel stops…

jUST FOUND MY MEMORY STICK AFTER ABOUT A MONTH, – i left it at work, and found my original ‘plastic forcing its way out of the ptfe/heater barrel – hence the need for the nut!

you can just see the white of the melted abs poking out of the central hole of the main washer – the second ‘bent’ washer was to stop the barrel from being forced out.