How to Polish Granite Edges

Granite is in igneous stone and made by cooling down of lava at high pressure. They are one of the harder stone, and has some pores as well. Polishing granite edge is a common task for any granite related DIY project and need little mechanical skill to get professional finish on edges.

Tools Needed:

• 4" Dry Polishing Pads Set
• Variable Speed Polisher Grinder or Low Speed Grinder
• Velcro Backing Pad Holder / Hook and Loop Backing Pad Holder
• Clamps
• A Piece of Wood

Step 1: Get a Good Quality Diamond Dry Polishing Pads Set

Polishing granite edge needs a complete set of diamond polishing pads starting grit 50, 100, 200, 400, 800, 1500 and 3000 grits. You need to use them one by one to attain the excellent finishing.

Step 2: Attach Velcro Backing Pads to Grinder

Attach the velcro backing pads to the grinder's arbor rotating clockwise and hand-tighten it so that it is not loose when working. Note always use low speed grinder or variable speed grinder for dry diamond polishing of Granite.

Step 3: Clamp Granite Firmly

Place a thin piece of wood over Granite and clamp it tight to prevent it from moving while polishing. Ensure the clamp is not directly on granite, and is over wood piece to avoid any damage to granite surface shine.

Step 4: Start Polishing With Grit 50

Now, you are start dry polishing of granite. Attach grit 50 dry polishing pad to the Velcro holder and run the grinder at low speed. If you have a variable speed grinder start at speed 2 or 3 that represents rpm less than 1000.

Step 5: Polish From Left to Right

While polishing, move the grinder from left edge of granite to right. Before you finish polishing with grit 50, ensure all saw marks and scratches are almost gone from granite edge. Position the grinder in slight angle and gradually polish the granite edges from one side to another. Be careful at bottom edge to remove objects, do it slowly.

Step 6: Move to Polishing With Grit 100

Now remove 50 grit polishing pads from velcro backer and attach the 100 grit pad, continue the same process like before. After successful polishing with grit 100, there should be any visible saw marks on edge.

Step 7: Move to Polishing With Grit 200

Remove grit 100 pads from backing pad and attach grit 200 polishing pads and continue polishing from left to right.

Step 8: Move to Polishing With Grit 400

After completion of polishing with grit 200, the surface should look very smooth however mostly no shine. Now you can move to grit 400 and continue the same process. At end of grit 400, you may see slight shine on granite.

Step 9: Move to Polishing With Grit 800

Now take out grit 400 pad, and attach 800 grit polishing pad and keep polishing from left to right. At this stage you would see slight shine on granite. For granite those are very hard, it is normal to not see any shine after completion of grit 800 polishing.

Step 10: Move to Polishing With Grit 1500

Now take out grit 800 polishing pads, and attach grit 1500 polishing pads to backing pad. Keep polishing from left to right evenly. At end of this stage, you must see low gloss to high gloss on granite edge. If some part of the granite has uneven or low shine, do polish more to achieve same level of shine across the surface. When you achieve same level of shine, you are ready to move to grit 3000 the final step of polishing granite.

Step 11: Move to Polishing With Grit 3000

Now take out grit 1500 pad and attach 3000 grit and polish from left to right, continue the process and stop when you are satisfied with the shine of granite.

Comments

[sixlidds]

My husband is polishing our granite countertop and is following these steps but there are circular scratches that are from the grinder. What is he doing wrong? One side worked out fine and then he did the other side and scratches everywhere but he thinks he did the exact same thing. I am adding water as he grinds at each step. Is that correct?

[beamkenny1]

The 800 gritt polishing pad is the last one that will remove imperfections (saw marks,pad marks, scratches, and other blemishes) Your last couple pads only add shine. So before you move to the 1500 make sure your 800 removed all the imperfections

[KellyCraig]

I believe that every higher grit is used to remove the imperfections left by the previous grit. I guess you could say, since each higher grit is to bring a higher sheen, one could say imperfections are in the eye of the beholder.

Dealing with rock isn't too much different than dealing with knife steels. To get to a high polish, for a high end knife that will see more "ooooh" "aughhhh" time than chopping at a branch requires going on up the grit or micron ladder. For example, I remove the imperfections left by my fine grit diamond stone on my buffer using jewelers rouge and chromium oxide.

I just cut a bunch of squares to cap wood posts for our dog run. I stopped at 1,500 for them. My counter tops, on the other hand, get the full treatment, 3,000 and even the buff pads.

[KellyCraig]

Those look like my dry polishing pads. I have used my dry pads with water and there were no issues.

Just curious.

Except on an installed surface where water would be a disaster (and after building tent to confine the mess), I try to work with water. The pads last so many times longer than the dry ones do.


That aside, in case you are unaware, you can buy stones that are just for granite work too. They are surprisingly cheap (they are huge, compared to what you might use in metal work).

Before I bought granite router bits (diamond embedded bits for rounding and profiling the edges), I did all my round over work using the stones by rolling the grinder up and down the edge to round it over.

After I was happy with the profile, I followed up with your approach, as you set out above.

It's a good idea to tape a line just to remind yourself where to stop, so you don't rough up more of the surface than you intended.

Even using my diamond round over bits, I like to knock off the sharp edges with the stones, to save wear and tear on the spendy router bits.

To any diving in, I highly recommend variable speed grinders over single speed, wide open ones, like the Flex I got off craigslist.

Wide open is okay, with a lot of cooling power, but when doing things like the stone round over, the slower speed is just a good plan.