Proper technique for scraping windows with razor blades is an aspect of window cleaning not often talked about. We know quite well about the functions and techniques of squeegees, stripwashers, water fed poles, and purification systems, but scraping windows is an enormous part of the job, and not an easy one, at that. You can cause real damage to your customer's property, which we all know, never ends well.
That’s why in this week’s Window Cleaner University article, we're going to discuss the proper way to use a razor blade for professional window cleaning and how to remove scratches if you make a mistake.
Before we dive into it, though, there’s something we’d like to note:
Before attempting to scrape debris off of your customers’ windows, we strongly encourage you to practice first on your own windows at home and on non-tempered glass. In fact, treating all windows as if they were tempered is a good rule of thumb to ensure that you don’t destroy or damage the finish once you do come across it.
Remember to always begin by applying the scraper to a tiny spot in the corner to make sure that you don’t cause unsightly marks in the center by mistake. Once you get the hang of using a scraper properly, you can then move on to scraping customers’ windows.
It is also wise to have your customers sign a waiver that can release you of any responsibility for possible damage that may occur while providing this sensitive service. This will let them know, too, how professional you are, and that you take your position and their property seriously.
Now that we’ve gotten this disclaimer out of the way let’s jump into the fun part: scraping off that stubborn debris that’ll make customers ecstatic!
Step 1: Wetting Down the Glass
The first and most essential step to scraping windows is to wet them down. Applying your solution with your stripwasher all over the glass provides a necessary lubricant for the razor to glide across. When you shave hair off your face or body, you wouldn’t normally do it dry. This is because applying pressure to a razor against a dry surface can cause skidding, scratches, or gashes where you definitely don’t want them. This same concept applies to glass: when you’re scraping debris off of glass, softening it with your solution and wetting the surface beneath it will help remove it, as the soap breaks it down and the abrasion breaks up the material. The water channels any debris away from the razor. If you were to scrape a dry piece of glass, you would most likely grind the debris further into it, leaving it there and causing scratches.
What’s more, is that you won’t be scraping every single window that you clean. Razors are typically only used to remove extremely stubborn debris, such as paint, bird droppings, stickers, graffiti, or tape, so make sure you save them only for the most stubborn jobs.
We would also suggest changing your scraper blades frequently. If you’re at a job such as a construction cleanup where you know you’ll be using your scraper often, it will be extremely helpful for you to change your blade in order to prevent rust, which of course, causes scratches. In addition, carrying extra blades with you is great for you to swap them out on the job, which in turn, increases your productivity at work while preventing scratches on the glass. Taking as many preventative measures as possible is the key to success: you can’t go backward, but you can think ahead!
Step 2: Removing the Debris with the Razor
Step 2 is the part you’ve been waiting for: actually using your razor for the job at hand!
How would we do this effectively?
Before you use your razor on the entire window, make sure to check one of the four corners for a tempered glass marking. Again, we do not suggest using a razor on tempered glass due to how easily scratched it can get with your razor, so proceed with extreme caution.
Now, let's get down to business and discuss the scraping technique.
By applying moderate pressure, you can start at the top of the window, then slowly work your way toward the sides of the window in a horizontal direction. You’ll want to make sure that the first thing you do is remove any of the debris that’s close to the frame. After working on all of the sides of the window against the frames, you should rewet the glass, then scrape the center of the window, making sure you’re removing all the debris while maintaining that same amount of pressure. After scraping the window, you’ll want to rewet the window again and use your abrasive pad to thoroughly scrub down the entire surface of the glass, ensuring you remove any of the debris the razor may have missed, all without risk of scratching.
Lastly, you’ll want to remove any of the water left over with your squeegee. If you find there is still debris left over, you can spot-scrub with your abrasive pad to eliminate any stubborn leftover particles.
Now, at WCR, we know that, nobody’s perfect. Even if you’re an absolute master scraper and you’ve been doing it for decades, there can still be that one-off chance where you just didn’t get enough shuteye the night before, or had a little too much sunlight that day, and make a tiny error.
What do you do when this happens?
Don’t sweat it! There are ways to solve this problem. Let’s dive in.
Oops! I Scratched the Window. What Now?
Let’s say you do scratch the glass with your scraper. First of all, don’t be too hard on yourself - these things happen, and can help you learn and improve upon your craft for future jobs. Second of all, causing a scratch may be a blessing in disguise.
You may be thinking, “Window Cleaner University, are you nuts?”
A little bit, yes, but also, being optimistic can be a little nutty; here’s why it couldn’t hurt:
Knowing how to restore surface damage such as scratches will put you a step above the rest, allowing you to add it to your docket of evergrowing skills, gain customers, and increase business revenue.
Customers need scratches removed all the time, whether they’re caused by extra hard water stains, building runoff, or even a contractor’s (or their own) mistake, scratches on glass are inevitable. Mishaps during construction, renovation, or human error, all cause scratches. You will need, however, the right set of tools for removing them, and the right technique.
One of our many configurations of the GlassRenu Scratch Removal Systemwill do the trick. This system is not only easy to use, but it provides distortion-free results and is faster than other systems on the market. Your repairs won’t take too long, so your customers will love that, and you’ll have created a great investment, as charging folks to have scratches removed isn’t cheap.
What you’re essentially doing is sanding down the scratch until it matches that of the surface, then applying a sealant so it stays protected. Feathering around it will help gain a distortion-free repair, and make the glass look 75%-95% like new.
Getting to Know Your Polisher
This GlassRenu System comes equipped with a polisher, also known as a grinder. This will be your main tool. It features variable speed, and comes with a guide that gives you revolutions per minute, so you can control how fast or slow you want your polisher to spin. Apply the trigger, and the polisher will spin. It works very similarly to a hand drill.
This kit comes also with different levels of abrasive polishing pads that easily attach to the velcro covered discs to make for a convenient and easy cleaning process.
You’ll want to screw the backing pads that come with this kit onto the polisher, and attach the polishing pads to them by the velcro. Before taking it to the window, you’ll want to take the temperature of the glass. You won’t ever want it to get hotter than 150°F. Apply some of your GlassRenu pre-polish to start onto the scratch, and with your gray disc attached, spin your system at around level 3-4, feather out, or go outside of the scratch, to make your surface nice and level.
Removing excess haze is important, and you can do this by taking a new pad and polishing the rest of the pre-polish off, and smoothing out the glass again at the grinder’s level of approximately 3-4. Two to three passes through the center of the glass will help, and you can go up, down, left, and right, repeating these movements until smooth. Make sure to keep checking the temperature of the glass so it does not exceed 150°F.
You will want to repeat these steps and eventually increase the speed of your polisher to remove the haze completely to gain a crystal clear finish. If you have any questions about this sensitive process, certainly don’t hesitate to give us a call and speak with one of our product experts. We can help guide you through the process through a video call. WCR has got you covered.
That’s Not All, Folks!
Still have questions? Don’t sweat it! If there is ever anything you’re unsure about, want to learn more about, or need advice for, do not hesitate to reach out to us. Window Cleaning Resource is here for you 24/7, with the help of our super-friendly window cleaning experts.
Having owned their own window cleaning business, too, they have tons of information on window cleaning products, business tips, and more, even if you want to just talk shop.
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