I was fitting a low profile shower try which requires it to be stuck to the floor with silicone. The floor is 3/4 ply so I cut an over sized hole in it to enable the trap to fit through and connect to the tray. I fitted the tray and the hole matched the cut out so stuck it all down. When I went t o fit the trap I realised that there is a flange all the way around it on w hich a rubber seal fits.
Most of the hole in the ply is fine except for a section (about 1/4 circle) where the flange hits the ply. Bloody typical! I don't want to cut the fl ange as I am afraid it will cause the gasket to leak so somehow need to tri m the hole. I can get access under the floor from besides the tray but the waste pipe and water pipes make access to the area very difficult.
I have tried chiseling from above which was partly successful in the I now have a sloped edge but can't get the chisel into a shallow enough angle to get the rest off. I have tried - a dremel type thing but only have sanding disks which bearly touch the wo od before breaking. - a right angle chuck to try and use a drill bit to "sand" the edge but no joy. I also tried one of those "saw" drill bits but they only "saw" mid wa y along the shaft
At the moment my only option seems to be to cut a hole in the ceiling below and access from there. As you can imagine this is not a popular option.
Anyone have any ideas?