In this work, we propose improvements on a state-of-the-art scheme for progressive triangular mesh compression, which is based on hierarchical vertex clustering. Specifically, we fix several shortcomings of that scheme including quantization error accumulation, false facet generation and lack of facet orientation encoding. In addition, the resultant mesh encoder yields better rate-distortion performance than another state-of-the-art one on our test model, as demonstrated by the experiments.