SDS drill: setting it up and changing the bit or blade

Learn to fit, remove and set up an SDS drill safely before you ever drill a hole.

SD-01Understand what makes an SDS drill differentSDS stands for the chuck system, not the drill itself - it lets you lock a bit in place without a chuck key. The bit has grooves cut into its shank that click into the chuck and let it move slightly in and out as it hammers. This slight in-out play is normal and not a fault - it's how the hammer action works.

SD-02Pick the right bit or blade for the jobSDS masonry bits are for drilling holes in brick, block or concrete. SDS chisels (pointed or flat) are for breaking out plaster, chasing channels, or light demolition - they don't drill holes at all. The beginner mistake is grabbing any bit that fits the chuck without checking it's the right shape for the task.

SD-03Fit a bit or blade into the chuckPull back the metal collar behind the chuck and hold it there. Push the bit's shank straight in as far as it will go, then twist it gently until you feel it drop into the grooves. Release the collar - it should spring forward and lock. Give the bit a firm tug; it should not pull out, though a small amount of wobble and in-out movement is normal.

SD-04Remove a bit safelyPull the collar all the way back - not just partway - and hold it there while you slide the bit out. If you only pull it back a little, the bit can jam or suddenly drop out and land on your foot or hand. Bits can be hot after use, so let them cool for a moment before touching the metal shank.

SD-05Set the drill to the right modeMost SDS drills have a mode dial or switch with three settings: rotary only (for wood or metal with an adapter, rare on SDS), hammer and rotary together (for drilling holes in masonry), and hammer only (for chiselling, no rotation). Turn the dial to the symbol matching your task before you switch the drill on - never mid-job. Using hammer-only mode with a drill bit fitted will wreck the bit and do nothing useful.

SD-06Set the depth stopMost SDS drills have a thin metal rod sliding through a hole in the side handle. Slide it so the length sticking out past the bit tip matches how deep you want to drill, then tighten the handle to lock it. This stops you drilling straight through a wall by accident or going deeper than a wall plug needs.

SD-07Before you drill or chisel into any wallA cable or pipe detector reduces risk but does not remove it - it can miss cables that are deep, run in metal conduit, sit behind metal-backed plasterboard, or simply weren't installed in the expected safe zones, especially in older or amateur wiring. Always expect something might be there and prove otherwise, rather than trusting a clear reading alone. If there is any doubt at all, isolate the circuit at the consumer unit before drilling, and turn the water off at the stopcock before cutting into anything that could carry a pipe.

SD-08Check you've set it up correctlyBefore switching on, tug the bit firmly - it should stay put with only slight in-out play, not fall out or spin loose. Check the mode dial matches your task and the depth stop is set if you need one. If the bit rattles side to side more than a couple of millimetres, or won't lock in at all, it isn't fully seated - remove it and refit it properly rather than drilling anyway.

Save this as a project

Back to all guides