Well the most important thing is to have a PROPERLY fitting screwdriver, the right size. It looks like it might be a little chewed up already... I'd get a little lube of some kind down there... and be patient! Cando
Make sure you use a real POZI screwdriver of a decent brand and neither a cheap one or a Philips. Push in hard as you try to turn and also try tightening too.
Is it a brass screw ? Often are (or stainless steel) so don’t rust If brass, the head will shear off easily from the shank, all good, then lift pan up over screw Can then remove what’s left with pincers / pliers / or bend and snap Head doesn’t look too bad, more likely the thread has corroded and stuck to timber Are you planning on reusing the toilet ?
Agree with FBN, try tightening first, but be careful there looks to be no plastic washer and you don’t want to crack the pottery. If you can get it to move a quarter turn tighter it often cracks the hold and let’s you reverse out, otherwise progressively larger drill bits until the head of the screw is reduced enough to lift it free then mole grips.
That looks like typical "Yellowed" steel rather than brass. How many times do you find pans screwed down or cisterns screwed to the wall with mild steel or yellow chromated screws that have corroded! Urine does a great job of starting corrosion!
I’ve given the OP 2 methods to remove the screw if it snaps, as we know, there are others - We also don’t know if same toilet is being refitted ? If new toilet, the footprint will differ so new screw positions Is same toilet and screw snaps in floor, screw can be budged a mm to miss existing screw Have you ever had to fit something in an exact position where one of the screws snaps in wall ?
Yeah maybe, couldn’t work it out on my phone, no idea if regular steel screw or a ‘gold screw’ type thing As I said, threads will be stuck to timber with a mix of urine and corrosion - it’s powerful stuff !
If the toilet is being disposed off, tap the ceramic around the screw with a hammer to break around the screw, then undo the screw with grips. Wear goggles and be careful of sharp edged
Hi guys sorry maybe I should have given you more information in the original post ideally I would like to keep the toilet but if it has to be broken then it has to be broken to get it out I have tried tightening and even moving the toilet sideways and up and down a little bit to train we did get out the problem is not the grip it's that the screw simply won't budge and that includes tightening and trying to unscrew is just totally jammed in
As RS Boats said above - drill the head of the screw away so your just left with the shank Use decent HSS drill bits, cutting fluid or paste if your bothered and work up the drill sizes. Protect the porcelain around screw with layers of masking tape or gaffer tape - that way if bit slips, bit of cushioning Will all be fine, just depends on quality of drill bits and how hard the screw is Once head drilled and toilet removed, several options to remove what’s left of screw - or at least have a try
Start with a 1-1.5mm drill into the centre of the cross, then a sharp 3mm - have it running in the drill as you introduce the hole. Go maybe5mm deep. Then move to a 5mm and that should be enough to break through and you will get a steel ring on the drill bit and just the shank remaining. Lift WC away and then mole grips to remove te shank.
BY look of it, screws appears to be going in more horizontally so might there be one of those plastic blocks used inside the pan base ? Might be worth considering seeing where the boards are nailed and use a whizzer saw to cut boards either side of pan, lift and make good after ? J