Very pleased to report that with using a x7 more expensive than my others carbide tipped drill bit designed for drilling into hard plate, and done at a slow speed with a drop of oil, it worked a treat and took only around five minutes to complete the job,which is a very different result to the 40 minutes of struggling and snapping normal HSS drill bits yesterday that did not make any impression on what I was trying to drill -the whole job made much worse due to it being under a car So thank you to everybody for the tips and advice