a lot of times the tips that come with solder-irons just dont cut it. just make your own. really a ton of material works. here i use the lid of a fish-can (although copper would be better, but i will make a quick & dirt ´knife´-tip for plastic-welding).
_ a solder-iron (nobrainer)
_ some kind of (thin) tin - (or just bang down some metal)
Step 1: Create a Piece of ´tube´ From Some Tin
_ cut a strip of metal-tin >
_ roll it up with pliers into a ´tube´ the size of the heating-coil of the iron >
_ flatten the end of the tube/tip; cut/file/grind in into any shape you wish >
_ connect tip with iron, ready
Step 2: Done
(above: parts before assembly)
thank to all.