When I started collecting rusty wrenches, I bought a glass beading system intending to use it to remove rust. Fortunately, I didn't get too far into collecting before I discovered the peening effect of glass beading. I asked my expert friends about that, and they suggested using walnut shells in place of glass beads. That seemed to be more trouble than it was worth. So I sold the beading cabinet to the company I worked for.
Next, I heard about cleaning tools with NaOH, and I bought a 5 gallon pail of the stuff from a cleaning supply house down in Wilmington. The stuff had to be diluted in water to use, and that was scary, both in the setting up and in the disposing. I mean this stuff is used to dissolve human bodies. We have a septic system, and there was no way this was going into that system. So, after a time I gave the still 98% filled pail of NaOH to the garbage guys.
Last, I tried washing dirty tools with Murphy's Oil Soap first if they are really dirty. That works well and it doesn't screw up wooden handles. I follow that up with judicious wire brushing, using a Dremel wire brush to get in crevices if its important enough. "Judicious" wire brushing is the kind that can take off rust but leave underlying paint, chrome, and nickel. Highly finished steel tool surfaces stain over time, and judicious use of a brass wheel brush can take the stains off. An old tool meister, Herb Kean, taught me that one.