This is another use for the heat gun: you can weld plastic with it. This is the attachment for plastic welding. You can insert the plastic welding rod into the hole at the top of the tip or you can use it without the rod as in this photo and just melt the pieces together. It looks like this flare was repaired once before since it has a 1973 red inner brace glued to it. Their glue didnt hold very well so I welded it to the flare and later followed up with a liberal smearing of 2-part epoxy.