I am looking for advice on cutting a large hole (about 4.5 inches diameter) through a 12″ porcelain tile. The tile is very hard and so far I have tried twice with a 4 inch smooth diamond blade and an angle grinder while spraying water on the tile. I have been starting from the back, carefully making a larger and larger groove as I work through the tile. I have been setting the tile on a thin rag on a piece of plywood to try to minimize vibration. I get about half way through and the tile cracks. Any advice on how to do it?
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You have a drill press where you can better control the pressure you are applying?
Thanks for the reply. No I don't but I think I could take the tile to a friend's house that has a press. Is the idea to drill multiple small holes to make the circle?
I just fought my way through this same issue.
If you look at rotozip bits, they say "will not cut floor tile". I tried anyway. then grit blades in a jigsaw. then grit blades in a Fein Multimaster. then myriad slots with my 4" wetsaw, then clip the scrap with tile nippers.
NADA - went through eight tiles - some of the way, then crack. Finally, the client volunteered that he didn't mind two extra grout lines around his shower control. I cut the tile in two, then sawed and nibbled out two "C shapes. No problem.
In retrospect, I think it's nearly impossible to cut big holes in hard tile, because you are putting a lot of energy into an object that can't locally deform to absorb strain.
Good luck - I gave up!
Forrest
Hmmm... that's what I was worried about. Well thanks for the advice. It is good to know that I am not alone with this issue. The darn tiles are 6 bucks each and it very quickly gets costly. I give it one shot using <!----><!----><!---->Norman<!----><!---->’s idea of drilling 1/8 inch holes in a circle and if it doesn’t work I will try to convince my client to go with the grout lines. The only problem is I have the toughest client ever- my wife! She encouraged me to try a message board and all of the responses have been helpful. I'll print your response and show it to her- might help me with “grout line buy in”.<!----><!----><!---->
<!----> <!---->
Thanks lots.
Outline the circumference of the hole by drilling 1/8th or 3/16th inch holes in a circle as close to each other as possible. Then break the webs between the holes with your choice of:
A RotoZip or Dremel with carbide bit
A larger drill bit run into the same holes
A carbide dust saw bit.
I'm sure others will have more ideas.
Gimby,
I have found that this is a very hard thing to do. What I do is to outline the hole with a score line, using the mini-grinder held vertically. Then I make 4 plunge cuts to remove the center of the hole as a square plug. Working from the edges of the hole, I then kerf the 4 resulting chords at their centers to give me 8 small arcs to cut off. Then back to the outlining with the grinder, leaning the wheel into the waste to keep the edges straight.
It is a slow, deliberate process of divide and conquer. I wish grit-edge jigsaw blades could do it, but they are powerless against really hard tile/stone. Careful application of high-speed diamonds seems to be the only way.
Bill
Do you have a good wet cutting tile saw? (with a top quality blade) If so, you can just outline the cut with a grease pencil and raise the tile up into the blade while holding it in both hands.
Make a whole bunch of radial cuts right up to the outline of the circle.
You won't have to put much pressure on the tile if the blade is good.
A tile split in half around a shower valve is the signature of an amateur tile layer!!!
Another way to do it , is to actually "glue up" the tile (making sure it is very well bedded) and then cut the hole (if there is nothing in the wall hole to interfere with tile installation).
Edited 3/14/2006 4:03 pm ET by BoJangles
Hey thanks BoJangles. I do have a wet saw with a good blade. It makes straight cuts very easily in this tile as long as I don't go too fast. It is the type with the stationary blade and sliding table. I'll give it a shot. The hole is about 1“ from the edge of the tile which adds to the challenge. But I am kind of stuck with it because I already laid the tile along the side (long wall) and back of the tub surround and want to maintain the same pattern. It was suggested to me that I make cuts from both the back and the front of the tile. Do you recommend making the cuts from both sides?
You will eventually have to make cuts from the back after you get all the way to the marks on the front.
The key is not to stress the tile. I have done this many, many times.
Be patient, it will pay off!
I resemble that remark!
I've done a LOT of tile - and have a couple of good wet saws. My contention is, some tiles have internal stresses that aren't compatible with a big hole. On the job in question, I puposely centered the 11-7/8" tile on the 6-1/2" shower valve hole, just to give the most meat possible on all sides.
I even saved one almost trimmed tile that cracked just on one side - that is, the tile is still in one piece. If it hadn't been for water soaking under the glaze, I wouldn't have seen the hairline crack.
That's when the client said - "go ahead and make two pieces!"
Forrest
Thanks that makes me feel better. I am quite the perfectionist about these things and this is driving me nuts! I have a feeling I am dealing with some of the nastiest tile out there. If I crack a bunch of tile and give in I don’t want to feel like an amateur!
If this is really driving you nuts and you want to spend the bucks, buy a diamond grit holesaw of the size you need. They have types that will mount on a drill and types that will mount to a grinder. You supply the water (a dribble out of a hose is plenty).
I used to have a vacuum base drill press that would attach to a slab for precise core hole drilling. After not using it anymore for many years I got rid of it, but still have the vacuum pump for some reason. Have to figure out something to do with it.
"A job well done is its own reward. Now would you prefer to make the final payment by cash, check or Master Card?"
I'm willing to bet that you didn't crack the tile with the sawing process. It was probably when you got to the tile nippers that you broke the tile.
A tile nipper acts like the snapper on a slide cutter when you try to cut a porcelain tile.
That said, maybe you just had a bad batch of tile?? ;)
Yeah, yeah, that must have been it - some cheap 1$ DalTile the customer picked up . . .
Forrest
Try this method.
Your angle grinder with the 4" smooth blade - not the turboblade- held on an ANGLE will make any hole you want, especially large holes. Just have patience and do not force the blade. Again - instead of grinding with the blade 90 degree to the tile, tilt the grinder about 45 degree and follow the pencil outline. Tilt the grinder to the inside of the circle.The blade can be wet or dry. To give you an idea what you are up against. Ceramic tile has a hardness of ca. 600, porcelain 3000.
Works for me anytime.
Yup that was the first technique (and the only one) I tried with a smooth diamond blade (a 4 " Bosch blade to be exact). I have gotten half way or more through making a nice angled cut and then SNAP! But maybe my grinder RPMs are too high? Even with water from a hose I could still see a bit of red at the blade edge.
there was probably too much stress on the tile. I usually put some cardboard on a piece of plywood. Make sure its absolutely flat. No pressure on the tile other than the grinding; you will end up with a sharp edge but that can be ground out with the grinder. If ALL fails - does the hole have to be round? maybe some straight angled cuts? Most fixtures have an escutcheon plate which covers a "lot of sins"
I've cut regular strength wall tile with a plain old flycutter, working from the back. I'd guess that won't work here, though.
You might try bedding the tile in a layer of plumber's putty.
happy?
Okay, what am I missing here? Why did you need to cut a round hole for a shower control valve? I've never cut a round hole for one before. Always a simple square cut because the valve plate extends over the hole and covers it.
Regardless if you really need a hole like you wanted the way I would do it if you don't have the proper hole saw would be to draw the circle on both sides of the tile and just use the tip of the wet saw to go around and score it on both side until it breaks through.
Thanks for more great suggestions. 20 bucks for a water jet cut at a machine shop sounds like a great idea. A good deal when it is 6 bucks a tile. I am definitely going to look in to that. I practiced making radial cuts (as originally suggested by Bojangles) with the wet saw last night on a scrap piece. I got pretty far and then it cracked. But I think if I go really slow I might make it. About the hole being round. The shower valve is round and it is designed to be flush with the tile surface and then the trim that goes over top only adds about 1/4" around the perimeter. So there is not a lot of room for error. In 20/20 hindsight I would have considered this when shopping for a shower set and purchased something easier to deal with. I have very good 20/20 hindsight.
I use a TM-7 blade on my Felker-150 for hard porcelains.For what you're trying to do though, I'm suprised a diamond blade in an angle grinder won't do the trick.I outline the circumference of the circle, then score that line with the angle grinder.Then I do what someone else posted...do plunge cuts, sort of like cutting the hole into slices of pie. Start with scoring, then move to full depth.Diamond usually won't heat the tile to the point of fracture, but an abrasive disc sure will.Diamond will also require minimal pressure to make the cut. Less pressure means an easier cut and less heat.Might be the tile, though...best of luck getting this done.
check machine shops in the area,ask if they have a water jet. will cut any shape you want.usally 1 tile they will get about 20.00,but it will be perfect. larry
hand me the chainsaw, i need to trim the casing just a hair.
Nah, the 50KW laser machining system two buildings over is what you need.
If ignorance is bliss why aren't more people
happy?
That sounds cool! I hear there's a WJ machine shop around here that recently demonstarted cutting an 18" aluminum block.
Next time I'll remember . . .
Forrest
Hey your advice to look into getting a waterjet cut done for that hole was awesome. It cost me 15 bucks but only one tile. I was up to three cracked tiles trying all of the other methods that were suggested all of which I think would work under normal conditions (and maybe more experience on my part). I just have some nasty tile.
So thanks man.
There are many good, and usually succesful, ideas in this thread. From painful memories one that I thought of first was the possibility of bad tiles. That is a reality and desparate measures are sometimes needed to succeed. To the hole saw idea I would add; immerse the tile in water. As much water as possible. Add a little ice if you can and cut very slowly. Plan on it taking hours so you won't be tempted to try to rush it. The distortion from localized heat is what causes the breakage. I've done this with the angle grinder and diamond wheel as well. I can't recommend anyone else do it, but I bag and duct tape the machine as much as possible and be prepared to make a mess! The divide and conquer is my favorite method. I also always work only from the backside except for final trimming the finished hole. If you get this down, you may be ready to cut a centered shower drain opening in a highly-figured piece of marble the customer picked out as a centerpiece for her shower.
A real pain....no easy answer. Used 12 X 12 porcelain on my bathroom floor.
My solution was to deal w/ it in the layout stage, min two tiles meeting at cutouts, four on a toilet flange.
Might be too late for you though.