Mitering porcelain [Archive] - Ceramic Tile Advice Forums - John Bridge Ceramic Tile


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06-10-2019, 06:24 PM
By mitering I mean cutting the edge at a ~45 degree angle, not cutting triangular tiles. Point is to make an outside corner without bullnose. I've seen it called beveling too.

I've got a saw that will make miter cuts but I need to do it on the inside of an L piece and that won't always work. Plus I don't completely trust it to make those cuts straight. I was going to do it with an angle grinder but that didn't go very well, and the "knife edge" chipped. I'm ok leaving a small square edge for safety, the gaps will match 1/8" grout joints so there's some room, but it's still risky. I did get over-ambitious and tried to make it pretty sharp and I was using a mesh RIDGID dry blade. I ordered what I hope is a better blade (, can't find a continuous rim 4-4.5" dry blade that will get delivered in a reasonable amount of time. Can I do this with a sanding pad on an angle grinder? I can go slow, I just don't want to wait over a week to get the tool I need from amazon.

Am I way off base? This is the inspiration here: Except my tools aren't as good, the tile they're using doesn't look glazed, and this guy is good at this.

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06-10-2019, 06:39 PM
Diamond pad on an angle grinder would take a long time on porcelain.

I usually do a quirk miter, where I leave a strong 1/16” or more of the square edge before the bevel starts. Makes it less likely to chip.

I’ve never done it entirely with an angle grinder. I cut the tile to size first, regular cut on the wet saw with saw head at 90 degrees. Then make repeated passes with the saw head at a 45, keeping pressure on the blade to keep it in contact with the tile.

For those inside “L” cuts, I’ll get as close as I can, then finish up the last inch or so with continuous rim blade on angle grinder. Lastly I’ll hit the whole edge with a polishing pad.

06-10-2019, 07:19 PM
Any recommendations on the tools involved and where to get them? Especially the continous rim angle grinder blade. I'm in MA too.

06-10-2019, 09:03 PM
Wet saw blade is a T3 razor. Contractors direct.

Grinder is a 4” makita. Blade is

Polisher for last step is variable speed, forgot the make. I use the 200 grit diamond pad

06-10-2019, 09:47 PM
I do it the same way as Lou. If you do without a wet saw, you just have to take a few passes to get your bevel 45 nice and smooth without chips. Always nice to polish off with a 50 grit if you got it.

06-11-2019, 12:50 PM
Thank you. The turbo blade makita blade is better than the continuous rim one here ( Is it because it's designed for harder materials?

This is a stupid question but is it just a terrible idea to use a polishing pad on a non-variable-speed angle grinder? Think I'll take my time and use a rubbing stone, I only have 9 or so of these to do.

06-11-2019, 06:43 PM
I just picture it taking a looong time and kicking up loads of dust. If you try it, let us know how it turns out.

FWIW, when I miter on the wet saw, I put the tile on a piece of cardboard so I’m able to slightly tilt it as needed. The whole process really goes pretty quickly.

06-11-2019, 07:35 PM
I didn't mean start with the sander from a square edge, just do most of it with the angle grinder then finish up with the sanding disk.

Tried it on the wet saw. Looks pretty nice but didn't dare go much closer to the edge than 1/16". I might try the cardboard trick.

This is taking a lot of edge-shaving cuts. Is it going to wear the blade out unevenly, make it cut crooked?

06-11-2019, 08:16 PM
Looks good, that’s pretty much what I aim for.

Can’t speak as to if it wears out the blade unevenly. I haven’t noticed it doing so, but I only do a dozen or so miter cuts fairly infrequently.

06-19-2019, 04:09 AM
@spacecadet, I’m in western mass. My goto is the grinder with a turbo mesh blade. RIDGID released a new blade at depot.. It’s $30. They have only been carrying them about 6mo or so. And it’s a 4 1/2” blade. The turbo mesh helps a lot with the dry cutting. And the larger diameter blade helps with the mitering game.. clamp it. If you don’t have a variable speed grinder for the polishing(I do not) I use my 20v grinder, and use the smallest amp battery have. Shoot for deeper than 45~. More towards 55.

06-19-2019, 05:08 AM
Essentially what I shoot for. Key is to have a straight cut, and eliminate the “round over” from polishing close to what we believe is the line.

06-19-2019, 07:26 AM
Thanks, Cory. I actually have that ridgid mesh blade. I tried mitering with it and it seemed to be going well but then it took some pretty sizable chips out of the front edge. I probably got over-ambitious and careless but it spooked me so I've been doing miters on my wet saw. Does that blade start to chip more when it wears out? That might be my problem.

06-19-2019, 08:59 AM
the direction of a dry blade needs to be from finished front surface towards the back. I have tried some mitering like the pictures and it works find on my wet saw... I was doing 11 degrees so I had to make sure my blade depth was set so it would not hit my rubber top table as there are only slots for 22.5 and 45.

06-26-2019, 09:49 PM

I’ve tried both using the wet saw to make a few passes and then going at it with the angle grinder. But for me personally it is quicker to go at it with the angle grinder from the start. Get it close to about 1/16 then hit it with my variable speed grinder with diamond polishing pads 50-100-200-400. Have had luck with the Pearl turbo mesh blade. Clamp down the tile and use a wet sponge it seemed to help with the chipping.


Tiger Mountain Tile Inc
06-29-2019, 12:18 PM
I would do it exactly like that Fine Home Building article (link above) shows. If you like, you can do the initial miter with a wet saw, switch over to an angle grinder to get it closer, then switch to a dry polisher with a 100 grit pad.

Or, if you want to use the polisher more, pick up a 50 grit along with the 100.

Make sure that you aren't getting the grinder too deep and the chuck isn't contacting the tile.

06-29-2019, 06:30 PM
If I shoot for 1/8" mitered corner joints and I keep cutting them the way I have been, that leaves a bit over 1/32" between the angled edges. The joints will be caulked with silicone. Is that too tight? I think I'm alright if they are a little wider so long as they are neat.

Any gotcha's to cutting tiles on one side of the corner with the 1/16" edge like I show above and the other side sharper? Reason I ask is one side of the corner has less complicated pieces and I'm less worried about screwing up with the angle grinder there.