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The study of vail roughness effects on model heat transfer in high Reynolds number shock tunnel flows of a few milliseconds duration requires the use of a rugged, fast-response calorimeter of known surface roughness. Models constructed of continuous thin copper sheeting over a solid Insulator substrate with rear thermocouples attached were developed for this purpose. TSut surface of the copper can be roughened as required and thus forms both aa unbroken model surface segment and a heat flux calorimeter. Conditions of heat flux and tunnel test time under which the gauge Is useful are shown by analysis. Results from calibration experiments and shock tunnel tests are discussed.