Trouble drilling into concrete garage floor

Hi everyone,

First time here - in need of a bit of help and advice. I'm trying to install a security anchor point into the solid concrete floor of our integrated garage. This involves drilling 3x 10mm holes for the fixings which the securing bolts screw into.

Having borrowed a friends 800W SDS hammer drill, I successfully drilled the first pilot hole and then the full hole. The second hole is proving more challenging - I keep hitting what appear to be pieces of flint, which stop the masonry drill bit in it's tracks.

I'm concerned about damaging the drill bit or drill, so have been limiting to bursts of drilling to 15-20 seconds and then attacking the pieces of flint with a masonry nail and hammer, before resuming with the drill. However the nails quickly blunt and bend. I'm using a vacuum cleaner to remove as much dust from the drilled holes as possible, in between each burst of the drill.

Does anyone have any advice on a better way to do this and more appropriate tools to use? I've been using a combination of the SDS bits that go with the drill and the drill bits which came with the anchor point (which is designed to be secured to concrete).

Should I bite the bullet and go and hire a much more powerful drill? Upgrade to better quality bits? Or use something else to attack the pieces of flint?

Many thanks for your time reading my post. I look forward to reading your insightful responses.

best regards,

Andrew

 

Had another good look at the drilled hole - 95% sure it's flint. What would be an appropriate diamond drill bit to use please? Not entirely sure what type to go for, based on a search of the Screwfix website.