I also have an ancient large Royal crosscut shreader that I bought from Sam's Club in Nov. 1999. The only time I've ever lubed it was when it seized up and I took it apart to see if I could fix it. (I found a piece of paper clip wedged between a couple of teeth.) Note: Reassembly is not a job to perform if small children learning new words are around. When running, it rattles and makes a horrible racket but it just keeps running. You folks are making me feel guilty for neglecting my maintenance duties. I guess maybe I ought to try a spritz of the Hornady One Shot that I use in firearm magazines and door locks, where the liquid carrier evaporates and leaves behind a dry lube.
I just pulled the original manual out and it doesn't even mention lubing the machine. Maybe they never planned on it lasting long enough to require it.
We all have a ton of excess gun oils from being tempted by the snake-oil salesmen, just use one of the oils that you no longer prefer to use on your guns - clear out some space for when vat cloned synthetic eco-sensitive vintage sperm whale oil makes an appearance.
I've been using the same crosscut shredder for years. Staples sells soybean oil infused ppper sheets that can lubricate a shredder and I haven't had any problems at all with my shredder and it gets used a lot.