Welding | Grinding Glass Damage Repair

Welding Spatter and Grinding Damage on Glass

Metal Grinding And Welding Splatter Damage Repair

Can Anything be Done to Restore the Glass?

Regardless of what you call it, welding splatter, metal grinding damage, or weld splatter, the issue here is that if you allow hot metal to come in contact with glass, it’s like a hot knife and cold butter!  If you’re going to weld or grind metal anywhere near glass, you must protect the glass. However, the fact that you’re reading this tells me you just might have welding slag on some glass! You probably want to know, “Can glass with grinding damage or welding slag on it be resurfaced and saved? The slideshow/video below was from a welding slag removal project performed in Century City, CA

The short answer…it depends! There are numerous factors that will determine if the damaged glass can be restored. First, if we’re talking about welding damage from slag, proximity matters. If the welding spatter has at least some time and space to cool before hitting the glass, the damage tends to be more spread out and doesn’t penetrate the glass as deeply. 

Welding & Grinding Damage Causes Pitted Glass

A good test for this is to take a razor blade and remove the welding splatter. If the metal was still very hot, it will form a little ball at the bottom and burrow into the glass and create a very deep round pit. Sometimes, these pits are too deep to safely grind out.

Even with tempered glass, if you grind deeper than approximately 1/10th of the glass thickness, there is a possibility the glass will shatter because of the tempering. So, remove the metal from the glass, assess the situation and send us some pictures and we will give you our best professional opinion on what can be done to save your glass.

We have seen workers cutting metal studs in front of unprotected floor to ceiling glass for hours on end, leaving thousands of metal specks embedded in the glass. For some reason most people are under the impression that if the metal specks aren’t glowing, they’re not hot enough to penetrate the glass, or the metal is just bouncing off the glass. It does seem to appear to do that but this is not the case. As many have unfortunately discovered, grinding or cutting metal in front of glass creates a nightmare of metal embedded into the glass. Even if they can remove the residual metal, there is still the problem of the glass now being pitted. With damage like this, it requires a much more aggressive method. If the glass is not tempered, usually this is not a good fit for glass resurfacing or restoration since considerable heat is created with severe damage as this.

Some Pitting Damage and Welding Spatter Can Be Removed - But Not Always

Don’t cut concrete encrusted steel in front of glass either!We’ve seen a project where they did just that.  The contractor was removing some steel post that were covered with concrete and had to be removed.  So his worker just went for it and cut it right in from of six storefront panels of glass. So there were pits from the concrete plus embedded pieces of metal in the glass!  This restoration job required some very aggressive grinding to get it done but we were able to do it.

***Recent glass grinding development for welding spatter and pitted glass*** [October 2022}

On a recent project with exceedingly deep pitting and  scratches, we developed a new glass grinding technique.   We found that, with the right density backing pad and a very aggressive grit, it is possible to remove significantly more glass than normally possible, WITHOUT distortion.  We were using our variable speed sander as an angle grinder!  Under ordinary conditions, this would create very uneven surface and disasterous distortion in the glass!  But we found with the right pressure and pattern, we can remove much more glass, actually “shaving” layers of glass down.  After the majority of the damage is removed, we revert back to sanding and pre-polishing, then polishing the glass with the pads constantly flat.  This has let to a huge uptick in our ability to resurface welding and grinding damaged glass much faster. A word of caution : DO NOT TRY THIS ON AN ACTUAL JOB!  Distortion will be instantaneous and irreversible if not done correctly.

When welding spatter is widespread. Additionally, this type of glass damage tends to cover a large area. If there is considerable amount of splatter or metal specks near the frame, it will be difficult, even for the world’s best glass polisher to remove all the deeper damage without leaving some residual distortion due to the lack of area to “feather out” the damage. Each grinding damage/ welding spatter/ glass project is unique and we take each one on a case by case project. We’re going to do our best to save your glass. Even our competitors say, “If Unscratch the Surface can’t get it out, no one can!” For welding & grinding glass damage repair, give us a call.  We are based on California.

Get an estimate

    1 +

    HAPPY CLIENTS WORLD WIDE