The "Impale Sticky" level of World of Goo is so difficult! How in the world is it possible to get OCD on this level??? I can barely get the minimum goo balls required to beat the level!
Basically, you want to brace your goo structure against the platform you start on. Build as close to the gears as you can without the swaying of the structure pushing itself into them. The last bit as you reach the top platform is timing; you have to wait to the platform to spring back into the position you want to.
It's hard to express it in words, so here's a good video illustrating what you should do.