Get an old solder tip and cut it at length exactly alligned on the top of the heat element, as seen on the following illustration photos here.

Step 1: Customized Hot Knife.

Cut a slit at the tip of the solder tip thru the dept that is alligned to the heat element screw that holds the solder tip, as seen on the following illustration photos.

Step 2: Customized Hot Knife.

Here are some samples of how it cut thru hard plastic materials.

You can also change the blade of what ever shape you prefer as long as it can go thru the hole that the solder tip can go thru.