To improve the cutting deformation of the weak rigid multiframe workpieces, the realtime adjustment of feedrate based on the realtime cutting force measurement is proposed. According to the milling finite element simulation, one kind of nonlinear numerical model with feed speed, cutting force and the maximum deformation of workpiece is formulated. The optimal feedrate under maximum deformation and cutting force are achieved. Meanwhile, the control module is developed in the open numerical control system. The cutting experiments of aluminum alloy thin wall frame are carried out by using the developed wireless force measuring device and control module. Experimental results show that prediction accuracy of the numerical model is over 90%. The cutting force and maximum deformation of workpiece are reduced around 23% and 123%, respectively. Experimental results show that deformation of the thinwalled frames can be effectively controlled within specified range by the realtime cutting force constraint and feedrate adaptive adjustment.