The paper considers the problem of online monitoring the condition of cutting tools to avoid its unexpected failure. To approach this problem we proposed a model of milling process based on Morlet decomposition of vibroacoustic signals. In addition, using the wavelets scalogram, we imposed a new condition that helps to improve early wear detection of the cutting tool. The findings of this research reveal the advantages of the proposed model compared to the previously reported models that rely on Haar wavelets and Short-time Fourier transform.