First of all, determine the extent of oxidation on the aluminum surface. If it is determined that the surface is in relatively good shape, i.e. light oxidation, then skip this step and move on to polishing with Flitz.
Q: how long can a usb printer cable be? I am trying to connect a HP laserjet 2840 to my iMac with a USB 2.0 cable that is 25ft long. The computer does not recongnize the printer or that it is connected when I plug them both in. The same 25ft cable works fine when connected to my other HP P1006 printer. The HP 2840 works fine when I use a shorter usb cable.
You can get a USB 2.0 cable for use with a device using USB 2.0 or a USB 3.0 cable for use with a device using USB 3.0. There are also USB extension cables that can connect to one end of a USB cable (typically the end that would connect to the computer) to extend the length of the cable. However, you should still avoid extending the cable beyond the 16 feet 5 inches total maximum length limit, unless using a USB hub to connect another USB cable.