A couple of art questions, semi-melted crayons, sharpeners, and short pencils

[JudiAU]

Can anyone recommend a specific sharpener for stockmar stick crayons?

I am asking for a specific recommendation because I badly cracked a lyra pencil with their branded wooden sharpener (plastic version works better) and I don't want to break the crayon with a random selection. Ours are flat as a pancake and difficult to draw with and the kids have been avoiding them and I'd like to give them a fresh life. Both kids seem to enjoy drawing more than coloring at the moment.  

Also, we took our block crayons on vacation and they were left outside in the hot, hot sun overnight. I was astonished to see that they were partially melted with clear wax oozing out them. I assume I need to shave or break off the areas without pigmentation but will they still work as crayons? Do I need to sacrfice them to sort of melting project. =(

Finally, can I do anything interesting with real short lyra pencils? Repurposed somehow?

[sprinkle pocket]

I think the stockmar sticks come with a scraper to sharpen or.clean them. Its plastic. Maybe if you don't have one, a plastic serrated knife could work? You can see a picture of it online to get an idea. My kids still use blocks more so we haven't needed any sharpening yet.
Super short Lyra? Hmm, what about telling a story based on Stuart little or some kids similar to yours that got shrunk and needed to write a note to their parents to help them but all the pencils were too huge and too heavy..until they found some tiny ones the kids.had discarded and ignored. Maybe that'd breathe new life into them. Or about how the elves that make Lyra pencils actually go around collecting short ones and soak them in an elfin hot spring and by morning they've grown long again. They dry them in the sun and put them in a new box to sell. Or that's how you could introduce a new.batch...;•)