In that case have someone else do it for you.
Here in the UK, a basic sealey sandblasting gun is around £30, without the blasting media.
For only £55, I can get an alloy frame degreased, chemically stripped & wet blasted, AND then have all the threads masked up, & have it primed and powdercoated in any single RAL colour I fancy. The cost for simply having the same guys blast the frame clean ready for my own paint would therefore be a fraction of the cost of buying the tools to do it myself, and the job would be much better too.
There's always a sense of immense satisfaction to be had from learning a new skill, or doing something yourself, but in this case, it's quicker, easier, better and cheaper just to let a shotblasting company do it for you.