CNC Tool Grinding machines are specialized machines that are used to sharpen and shape cutting tools, such as milling cutters, drills, and endmills. The best-selling CNC Tool Grinding machines can vary depending on the specific application, industry, and region. However, some popular and widely used models include:

1. Walter Helitronic Vision – Walter is a well-known brand in the CNC tool grinding industry, and their Helitronic Vision machines are known for their high precision, efficiency, and versatility. They offer a wide range of models for different applications and industries.
2. Anca MX7 Linear – Anca is another well-known brand in the CNC tool grinding industry, and their MX7 Linear machines are known for their high precision and reliability. They offer a wide range of models for different applications and industries.
3. Schneeberger Norma – Schneeberger is a well-known brand in the CNC tool grinding industry, and their Norma machines are known for their high precision and durability. They offer a wide range of models for different applications and industries.
4. Junker Quickpoint – Junker is a well-known brand in the CNC tool grinding industry, and their Quickpoint machines are known for their high precision and efficiency. They offer a wide range of models for different applications and industries.
5. Rollomatic ShapeSmart NP5 – Rollomatic is a well-known brand in the CNC tool grinding industry, and their ShapeSmart NP5 machines are known for their high precision and productivity. They offer a wide range of models for different applications and industries.

It’s worth noting that the best-selling CNC Tool Grinding machines also depend on the region, some brands might be more popular in one region than another. Also, the best-selling models change over time as new technologies and models are introduced, so the list above may not always be the most up-to-date.