Chrome plating? This thing was originally designed (by me) to provide 6 Amps, it will do 10A without problems. The application was anodizing. If you want more information, look for a thread "VCCS Questions" active in Oct. 2003 in this forum. You'll get the complete picture on ripple reduction capacitance, they were discussing values on the order of 27,000 uF. The heatsinks were on the order of 0.7 deg. C. per Watt. Forced air cooling was also intended.
The limiting component(s) for current regulation and drift are the three paralleled source resistors, they are cheap wire wounds. The opamp, voltage reference, and the ordinary carbon film resistors are negligible here.
As shown this circuit will provide both current regulation and drift to better than +/-1% over a 10 mA to 10A range, and was tested to that. Why would it need to be any better for anodizing or plating?
The limiting components for power dissipation are the three paralleled MOSFETs. Although these MOSFETs are rated for 55A and 115W each, the thermal resistance of the TO-220 MOSFET package to the heatsink lowers this considerably, which is why there are three. Using MOSFETs with TO-247 or TO-3 packages will improve this considerably.
Raising the value of the source resistor(s) will only serve to reduce the voltage compliance, why would you want to do that?
A nicety would be to use the other half of the dual opamp as a gain of +10V/V amplifier for the current monitor, now it will read directly, 1V = 1A. For this, I would use a better opamp; say an LT1013, and 1% metal film resistors in the current monitor amp.
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