If you've lost the little yellow plastic tool that comes with a Tech Deck Skateboard, don't panic. You can still tighten the trucks or make other adjustments to your Tech Deck. You can easily purchase a screwdriver that is the right size for Tech Decks, and create a tool that will replace that tiny yellow wrench out of common household items.
Purchase a small screwdriver that is the correct size for the black screws that hold the truck, the metal wheel assembly; to the Tech Deck board. Screwdrivers of the correct size for Tech Deck screws are commonly available. Use this screwdriver to tighten or adjust the screws holding the truck to the board.
Create a hole in the centre of a pencil eraser using a thumbtack or pushpin.
Use the pencil as a wrench to tighten the nuts which hold the wheel to the axle. As the nut tightens and reveals the axle, let the axle slide into the hole you created with the pushpin. If this doesn't work, reinsert the pushpin into the hole in the eraser and wiggle it around to enlarge the hole, then try again to tighten the nut on the axle.
Remove the plastic pipe from a disposable ballpoint pen which contains the ink. It is not necessary to remove the ballpoint assembly, which could cause a messy ink spill. Carefully cut a notch one to two millimetres long down the side of the plastic ink tube, starting at the open end. You can use this ink pipe as a wrench to tighten the hard to reach nut underneath the truck of the skateboard. This handmade wrench can also loosen the wheel nut from the axle.
The screwdriver from an eyeglass kit will also work for adjusting the screws which hold the truck to the Tech Deck board. If the wrench you create from the plastic ink pipe doesn't work, snip the end off with a pair of scissors or a fingernail clipper and try again, cutting a shorter notch with the hobby knife.
Be extremely careful when cutting the notch into the plastic ink pipe with the razor sharp hobby knife. Adult supervision may be required.