Difficulty drilling into wall

Discussion in 'Builders' Talk' started by Festool Frenzy, Mar 18, 2019.

  1. Festool Frenzy

    Festool Frenzy New Member

    Im fitting a bookcase which require lots of holes drilling into a wall at various points. The wall is very inconsistent in density varying from easy drilling to almost impossible. I have blunted flat 3No. 7mm SDS drill bits now.

    Its a bungalow. Using a corded 110V SDS with good quality Dewalt bits.

    What could be behind the plaster that is so difficult to drill?
  2. KIAB

    KIAB Well-Known Member

    Could be something like the very hard Accrington brick.
  3. Festool Frenzy

    Festool Frenzy New Member

    That is possible. Its a Sheffield bungalow that is something between 30/60 years old as a guess. Would you get that sort of brickwork on a building like that?
  4. Heat

    Heat Well-Known Member

    Try drilling first with a smaller drill like 5mm first and later use the 7mm.
    Keep dipping the drill bit into a bowl of water after every few seconds of drilling.
    Try Bosch blue multi purpose drill bit sets. (Screwfix does them at good price). They get a great reputation, although I haven’t yet tested mine on extremely hard brick
  5. chippie244

    chippie244 Well-Known Member

    Is it brick or something else?
  6. mitefix

    mitefix Member

    Could be clay salamander block
  7. Wayners

    Wayners Well-Known Member

    DeWalt Extreme 2 Masonry.. Don't go to fast as some go flat out. Steady speed so they do something rather than skip over and burn out.. Take it easy
  8. MalcyB

    MalcyB Member

    I did some work on my daughters house, I think it was an old RAF house near Gainsborough. I went through SDS bits like mad on the internal walls of that. Up in the loft I could see that the walls were coated in what I can only describe as pebbledash. I thought I had a picture on my phone to upload but I can't find it, sorry.
  9. rogerk101

    rogerk101 Well-Known Member

    If you overheat a drill bit, its metal will become soft and useless.
    As Heat says above, keep cooling it down with as much of a thermal shock as possible. If the water you're using for cooling warms up from all the dips, then replace it with the coldest water available. The drill bit must cool down WITH thermal shock in order for the metal to remain hard.

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