Drilling a hole in a toilet tank

Question

I need to change or replace the left-hand flush to a right-hand flush, due to ADA. The toilet is about 15 years old and was manufactured in Turkey. I've pretty much have given up on locating a replacement tank. Drilling a hole and repositioning the lever seems to be the least expensive route. I believe I would need a diamond drill bit or hole saw. Plan B would be to replace the toilet. Any guidance?

Answer 1

I have done this in Porcelain a few times using a diamond tip tiling holesaw. I drilled 3/4" holes in 1/2 thick porcelain tile very cleanly with NO hammer action. These holesaws are not cheap but less than the cost of a new tank. I got mine at KMS Tools, Coquitlam, BC for around $60
Practice on an old toilet tank first.

Answer 2

Prick the glaze with an awl... carefully, to establish your starting point. Then drill, low speed with minimal pressure to minimize heat. Cool the bit and porcelain with water as you drill using a standard masonry bit. Resist the urge to push, have patience. Should be no problem with due care. Do not use a hammer drill.

Answer 3

If I was going to do a high-risk drill job like this (and I would try it before I'd pay for a new tank), here's what I'd do:

1. Pad the tank with towels, foam, or whatever you have on hand to dampen vibration. That's what will shatter the porcelain. Use some squeeze clamps or stuff the tank full and snug to apply pressure against the tank wall.
2. Use a carbide masonry drill bit with a high-rate hammerdrill. I mean what you find in a cordless drill, and not a dedicated industrial hammerdrill. The smaller and faster the hammer action, the less likely you are to shatter the tank. Start with a small bit and work up: Maybe 3/16" initially, and 1/6" increments.
3. Use a sharp hardened punch to chip the surface where you intend to drill. Even a hammerdrill will walk away once you apply pressure. That will be frustrating and damaging to nearby objects.
4. Spin fast, press slow. Use your drill's highest speed, but press very lightly. The smaller the bites, the better. The outward pressure of the bit when enlarging a hole is a concern, so go even easier after the first hole.
5. Watch for heat. I don't expect a lot of heat with this method, but if it gets very hot you'll possibly scorch the finish. You could also melt the bit or wreck its temper.
6. Back off even more as you get through to the inner face of the tank wall. If you're pressing too hard you'll blow out the back side. Brace your hands and make sure the drill doesn't plunge through after penetration.

More information from a previous question

That's all I got. I'm not an expert with ultra-hard materials, but I've done my share of experimenting with tile, countertops, etc. Good luck.

Answer 4

I have experience drilling holes in glass, it seems ceramic is more forgiving than glass when it comes to thermal shock when drilling/cutting, but still an issue. I plan on drilling a hole in my toilet tank using a diamond hole-saw drill bit. While letting water flow over the area I'm drilling, to keep it cool (since submerging it completely isn't an option.) if this doesn't work I will report back here.