I am thinking about a hotend which can be made without soldering. The idea of crimping the barrel came up in the reprap forum. After some discussion I suggested something like the following solution.
To be honest I don't know, if I prefer such a solution. What I don't like about it is that the nozzle has no contact to the bottom of the heater block. The head of the screw will have a cooling effect on the nozzle this way. It should touch the heater block thus.
Maybe this solution is better: