I'm sure most of you know of the Tamiya sanding pencils and sanding sticks. While they are nice, sandpaper isn't exactly immortal. Resin or plastic clog up the grit, metal rips the grit off, etc. And me being the cost cutter that I am, I wanted to find a more cost effective solution.
So one of the tool hacks I came up with once I started working on metal miniatures again was to make these sanding sticks. Each handle is simply an Xacto blade wrapped in gaff tape for better grip. I then cut 5mm X 30mm strips of fairly stiff sandpaper and fold each strip in half, placing where the blade would normally sit. Needle files tend to clog and dull easily with metal minis or the grit is often too coarse for a smooth finish, so sandpaper makes a better fit. My main type is 500 grit paper that is sold at Harbor Freight. 7 panels at 9"x11" for just a few dollars which is enough to do a couple hundred metal models. 500 grit seems to be the sweet spot for metal minis as you can get close to a mirror finish, the only drawback is that they tend to wear out somewhat quickly. To double the mileage on them, when the first end dulls I simply swap it around in the handle and use the non bent ends(which work particularly well for smoothing out large surfaces like big armor pieces or flat surfaces).
I have 4 different handles that I use(though the gold one does most of the work) but that's simply because I had them on hand already and it cuts down a little on time spent refilling the sandpaper. A single handle will do just fine and costs under $3.