This work investigates the dry turning of polyoxymethylene reinforced with \(25\%\) fibreglass (POM C GF25%) with a carbide insert, following an orthogonal Taguchi \(L_{32}\) experimental plan. The influence of the four cutting parameters (nose radius r, cutting speed \(V_c\) , depth of cut \(a_p\) and feed f) on surface roughness ( \(R_a\) ), tangential cutting force ( \(F_z\) ), cutting power ( \(P_c\) ) and cutting energy ( \(E_c\) ) is first quantified by ANOVA and described by linear-with-interactions RSM polynomials, which serve as an interpretable parameter-effect analysis. Five machine-learning regressors (SVR, Random Forest, Gradient Boosting, XGBoost and a Deep Neural Network) are then trained on the same \(L_{32}\) data and compared by five-fold cross-validation; Gradient Boosting and XGBoost emerge as the best generalisers and are retained as per-output surrogates ( \(R_a\) , \(P_c\) : GB; \(F_z\) , \(E_c\) : XGBoost). A Gaussian-process smoothing of these surrogates is used as the objective function of four metaheuristic algorithms (MOALO, MOGWO, MODA and MOGOA) to construct three bi-objective Pareto fronts: ( \(R_a\) , \(F_z\) ), ( \(R_a\) , \(P_c\) ) and ( \(R_a\) , \(E_c\) ). The four algorithms produce essentially overlapping fronts. The two main contributions of the study are (i) the experimental characterisation and modelling of POM C GF25% machining and (ii) the use of cross-validated ML surrogates, in place of the conventional RSM polynomials, as the objective function of the multi-algorithm metaheuristic search.