Recenze společnosti Eternal Tools

Thanks for your feedback Jamie. We also do a 10mm with a 3mm shank that is suitable for a normal drill (LDBB10) this is also a coarser grit (80 grit) than the burr you ordered so will remove more material, and quicker.
The LDCB10/235 you ordered is 120 grit and has a 2.35mm delicate shank which is intended for hobby drills and pendant motor's.

Thanks for your feedback. One of the team will be in touch to double check you're using the bits correctly as we would normally expect 10 - 20 holes on something such as a porcelain tile. (low speed of about 5,000RPM, plenty of cold water and little pressure)