Best remedies to fix scratches
Do-it-yourself kits can work, but serious divots are best left to the professionals
Q I've discovered scratches on the glass top of my relatively new (and custom-made) coffee table. Is there anything I can do to get rid of them, short of replacing the glass?
A There are quite a few home remedies that supposedly get rid of scratches on glass: toothpaste, baking soda, metal polish, superfine steel wool, clear nail polish. The nail polish, like some scratch filler kits on the market, is for filling deep scratches — significant enough to catch a fingernail — and divots caused by flying rocks, as in automobile windshields. The other methods, supposedly, work for fine scratches.
But the catch is that to truly remove scratches, you need to wear down the surrounding glass so that it's even with the deepest part of the scratch. And you need to do that over a much wider area than just where the glass is scratched. Otherwise, the surface won't look flat. If you're using something like toothpaste, which has to be gentle enough to not wear off tooth enamel, it's going to take many hours to wear down the glass sufficiently to erase even fairly fine scratches.
Ethan Currier is a stone sculptor whose granite figures that ride a unicycle or clutch balloons delight visitors to Bainbridge Island, Wash. But he also erases scratches from glass, work he got started on when he had a yacht-maintenance business. On boat windows, where mineral deposits as well as fine scratches are an issue, he uses Brasso metal polish with a three-inch-wide foam pad in a rotary grinder at a slow speed, around 400 r.p.m. Metal polishes contain very finely ground abrasives; with Brasso, it's pumice, a natural mineral spewed out as a bubbly glasslike material by volcanoes. On what's known as the Mohs hardness scale, pumice is 6.0 to 6.5, only slightly higher than glass, at 5.5. By polishing a window over and over, he can get the glass clear again. But it takes him about one hour per square foot of glass.
When he confronts deeper scratches, he uses stone-polishing equipment and a collection of abrasive pads ranging from a relatively coarse 200 grit to a finer 1,000 grit. (With grits, the bigger the number, the smaller the abrasive particles.) He uses 200 grit until the scratches disappear, then works up through several more grits to get to 800, at which point the surface looks smooth and level. At 1,000 grit, it's polished, and he's done.
Mark Vilhauer, who, along with his wife, Heidi, runs the Surface Mechanix glass restoration company in Silverlake, Wash., uses a similar process, with a motorized polisher and various compounds and pads to abrade the glass down to the bottom of the deepest scratches, then buffs the glass and polishes it.
For a small job, like removing scratches from a coffee table, the company would ask the customer to mail the glass if driving is not feasible. To remove scratches from a glass coffee table about 18 inches wide by 30 inches long, the company would charge US$100 to US$300, depending on the severity of the damage.
Surface Mechanix uses products from several companies and is listed as one to call on a website maintained by Glassrenu, a company that sells tools and kits for taking scratches out of glass and has videos showing the process on its website. The equipment isn't expensive for pros investing to get started in a business, but it's more than a homeowner could justify as a way to get scratches out of a single glass tabletop. Glassrenu's Professional Kit XL is US$426.99 at Zoro. com; you'd also need a six-inch grinder, such as Makita's 13-amp corded cutoff angle grinder and a seven-inch variable speed rotary polisher. Paying a pro to do the work would be cheaper — as would buying a new piece of glass.
However, if the scratches are shallow enough that you can't feel them when you run your fingernails across, you have another option.
For do-it-yourselfers, Vilhauer recommended buying a glass scratch removal kit with cerium oxide (an abrasive) and a felt buffing wheel or pads that can be used with a cordless or plug-in drill. A kit from Yanmis with wool felt polishing wheels and polishing pads, sandpaper in five grits from 150 to 7,000 (in case you want to try removing deeper scratches) and 230 grams of cerium oxide is US$21.17 on Amazon. If you use the sanding discs, wear a dust mask rated for N95 filtering of fine particles, and consider working outdoors, where air circulation is excellent and where the glass dust and any bits of polish that go airborne won't be a problem. Don't expect instant results, though. Wrote one reviewer on Amazon that gave this kit a five-star review: “As with all glass polishes, this is a long and messy process.”