How to remove aluminum

[DonPenguino]

While this isn't a frame building question, it does have to do with metalwork which you guys might know a thing or two about...

I'm trying to remove the splines from an aluminum cassette cog for a project, but I can't figure out how. I tried a dremel with a pretty standard grinding wheel, but as expected it clogged in about a second. Any tips as to what tool to use?

[Dr.Deltron]

Any tips as to what tool to use?

Use the Dremel, except use a metal cutting tip, NOT a grinding wheel. Or, the emerypaper sanding drum bit, but they wear out pretty quickly. Check Home Depot, they carry all the Dremel bits.
Grinding wheels are for ferrous metals (steel, iron) and WILL clog if used on aluminum, brass etc.