Grinding / Polishing / Small chips

[Flintstone]

I think he means a flat side like the montolit has will rip it up on the upstroke, when the wheel is coming back up

 

[Julian 'Farmer' Bonsall]

@Localtiler ok think i understand - but that's how I have use the side of my cutting disc to grind in the past. Disc perpendicular to the tile surface, disc touching biscuit and ultimately glaze - outer radius/rim of the disc slightly protruding the glaze. It has worked well for me but my concern was I am wearing out the side of a blade in a way it wasn't meant to. With a backing pad / paper are they not used in this way? Or are they used at an angle across the tile face? Sorry for not understanding.

 

[Concrete guy]

I think he means a flat side like the montolit has will rip it up on the upstroke, when the wheel is coming back up

Exactly that, the curve allows you to be quite accurate with the cutting surface. A 125mm Flat vanity blade is touching 125mm of material pretty much all the time.

 

[Julian 'Farmer' Bonsall]

Sorry to be thick but isnt that whats happening when I use the side of a cutting blade? Why is that a bad thing? (you can always move the front or back face away?). A 125mm disc will only touch on the coated band and if the blade is circumference is slightly protruding the surface of the tile then there wouldn't be a lot of contact (depending on tile thickness) ?
Would a video of how I use the blades help to explain what I mean?
I just felt I would want a flat blade but maybe I am not using it correctly?

 

[Old Mod]

Would a video of how I use the blades help to explain what I mean?

Yes it would.

You keep saying you hold the blade perpendicular to the tile, and that you’re using the side of a cutting blade to tidy an edge.
That would mean you’re holding the blade parallel to the tile
To hold something perpendicular, would mean to make a T shape with blade and tile.
And if you are ‘toeing’ in the front of the blade, or indeed the back as you describe, then a slightly convex blade would do this for you.
Which is exactly how the grinding blade is designed.
These processes don’t take 5 mins on a sat afternoon to perfect, they take time and many lineal metres to get even half right.
As far as blade catching the glaze on the ‘up stroke’, of course it will, that’s not a revelation.
Any kind of sanding/polishing action is done in the direction of the grain and with the rotation of the blade. You should move in one direction, so that the downward rotation cuts through the glaze first and then the biscuit.
It’s no fault of the blade that it catches the glaze on the way back up, it’s down to incorrect technique.
Sorry if that sounds harsh, but that’s what it is, incorrect technique.
If you can make a flat blade work for you, then that’s great.
And every single tile behaves differently to the last, if they didn’t, then we’d all use the same blade, but we don’t
The effectiveness of any blade is down to two things, material and technique.
There is no one answer, it’s a subject that changes every day, with the introduction of different materials and different blade technology.

 

[Julian 'Farmer' Bonsall]

The disc is perpendicular to the tile (being the workpiece. Tile is held as shown in the images - glaze forms 90 degrees to the disc. If one uses any form of chop/sliding saw you typically set the blade at 90 degrees to your work piece ie perpendicular. I usually hold the blade stationary and move the work piece along it.

" Disc perpendicular to the tile surface, disc touching biscuit and ultimately glaze - outer radius/rim of the disc slightly protruding the glaze "

I will take some images as it will be safer than a video.

I suggested that the axis of the blade could be rotated to allow the front or rear to touch - I hold it so all axis are kept perpendicular to the tile so I grind it flat (seemed logical to me rightly or wrongly).

The way I have used the side of a cutting blade such that it is flat across the face of the tile was purposeful rather than using it at an angle which is a little how I feel the convex blade is behaving. As you can see from my images it works but it's different to what I was used to. How do you keep the cut face of the tile flat with the curved disc?

Moving to the silicon paper / flex backing pads - are these used at an angle to the face of the tile also?

I appreciate your help 3_fall and hope I haven't caused more greyness I am sure it's frustrating reading.

I have been tidying the edge of tiles up as I describe for a lot of years and maybe I have been doing it wrong and now a little confused.

 

[Old Mod]

There’s no right or wrong way ultimately, if your technique works, why second guess yourself and change?
I can only see a benefit in changing methods if it drastically reduces working time.
Other than that, why bother.
As I said, every material is different, working with thin tile this is never more evident.
What blade will give a clean cut on one, generally doesn’t on another.
Bolstering my belief that every manufacturer needs a specific blade for their material, change material and use the same blade, it’ll mostly gives an inferior cut.

 

[Julian 'Farmer' Bonsall]

Some images to help.

One image with pencil on the cut face shows the contact area with the 115mm disc on this tile (thickness shown in an image).
I have also shown one image of a miter which was cut (not ground) and had water applied from a small bore pipe application.

 

[Julian 'Farmer' Bonsall]

Originally his started out as a concern regarding the single face wear to a cutting blade and then looking to use a flexible paper on a backing pad to do the same job.

Are there any instructional video of how to do the job I am attempting ?

 

[Bill]

The tiles you are cutting have a thin glaze/top layer, chipping will be hard to avoid without a decent wet cutter.

Work smarter not harder.

 

[Julian 'Farmer' Bonsall]

Tom - that particular floor tile was a stand out problem from tiles I have cut previously and selected due to the easy chipping and the dark colour to show the effect of the electroplate blade. The original cuts were done with a wet cutter using a Marcrist 180mm blade (Sorry I cant remember exactly which variant - its was from screwfix)

These cuts were done with a battery grinder as a way of showing what effect the new tool (the Electroplate grinding disc).

The close up images of a cut with minimal chips was done wet with a CK650 blade (almost new) in a battery tool. The mitre cut I have shown was done with the same blade which I dont think look bad? Or are they?

 

[Julian 'Farmer' Bonsall]

Well I wanted another try at the wet sponge method and also to use a makeshift water lubrication system. I was going to try the Silicon Carbide discs but I incorrectly set up my polisher which destroyed the back pad in less than a second.
First is a dry cut (spanner for scale, yellow paint to help the camera focus).
Second a wet cut using a water flow to the front of the blade.
Third was with a wet sponge. I used a thinner sponge (not a car type, much thinner) and it worked a treat. Make sure you have the guards on properly.

I also tried some Production 120 Wet and Dry paper (a low cost brand), in a flexible sponge wet block. It appeared to remove the glaze (biscuit much easier) slowly but left a nice edge - a patient process.