Fred it is not that you, (oh exalted one) can't clean an axle with mear stone knives and bear skins for tools. It is more that it can't be done well (even with plasma)in that kind of time. What I mean by "well", takes the fastest tech I've got a good 2-3 hours. The result however...the axle housing looks better than new. No rust, no dirt, no old paint and a finish that has no gouges, pits or even sand marks or poorly sanded waves. Is is possible to cut that time down and have an axle that looks ok, sure. Depending on the shop doing this job (never seen one that makes a housing look like new like we do)but if they take pains to do a top flight job, it will look like it and it will cost.
Shops that do this sort of work everyday take pride in a job well done and they have something you don't...overhead.

SD