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Friday, January 11, 2019

The Cause of Scratched Glass & How To Protect It - A Quest For Answers

Did the IWCA test disprove that glass fines/particles can fuse to glass?

For decades now, window cleaners have reported encountering glass with a “rough surface” that has a “drag sensation” and also many times exhibits a “tinkling sound” when a razor blade is passed over the surface.  Both the roughness of the glass and the tinkling sound does vary from window to window.  This type of surface has historically been described as being impregnated with fabricating debris in varying amounts. Historically, “fabricating debris” has been described as particles that were not adequately washed off prior to entering the tempering oven, thus getting fused or “baked” onto the surface during the tempering process.  Such particles could be glass fines resulting from the scoring and cutting of glass sheets.  Or sand/silicate particles from atmospheric conditions inside the glass factory.   However, research by the IWCA in recent years has shed light on some inconsistencies in that theory.  First, lab tests that attempted to fuse glass and sand particles failed. After heating and cooling glass at the industry standard temperature of tempered glass, particles with the same coefficient of expansion as glass, and silicate particles did indeed fail to fuse to the float glass surface.  Such particles simply "popped out" after they were pressed in.  The simple answer then to the above question is an absolute yes.  It is not only plausible but also quite possible and very probable.

Microscopic Analysis;... What of It?

When this information was presented to me my first reaction was to simply get out a microscope and look at the animal.  Isn't that what we do with everything? Richard Feynman used to say, "look at the animal". So this is what the IWCA Glass Committee attempted to do.  Very powerful microscopes were used to attempt to see fused particles on actual samples of offensively scratched glass "from the field".  However; such particles could be identified!  So it was not possible to actually "see" what our ears were telling us was there.  Several years passed as the IWCA went through this phase of exploration.  This was the most irritating exercise in futility.  But it did serve as an educational experience for everyone involved.

So, after more than five years of searching, no actual physical specimens of glass tainted with fused fabricating debris have been delivered to the IWCA. However, the Glass Committee was able to gather scratched glass samples from actual construction sites in all parts of the country.  Sure enough, these scratched glass samples exhibited a “rough surface” whereas many times similar glass windows on the same job site exhibited a smooth surface and did not scratch even though the same cleaning methods were used.

Nano-Scale Roughness Exposed

At last years IWCA Convention we introduced the idea that the rough surface of glass that appears more likely to scratch could be due to a change at the microscopic or even the nanoscopic level. From this the IWCA introduced the term nanoscale roughness.  In fact there is an entire field of science that discusses how surfaces with a nanoscale roughness may be more prone to physical damage.  3D surface metrology is a very real science.  The question remained however; how do the “rough surfaces” and that "tinkling sound" which are encountered in the field originate? Do they develop during the tempering process? Or are there other considerations? Could the development of "nanoscale roughness" go back to the actual float glass process where glass is made on a bed of molten tin - producing what is known as an “air side” and a “tin side”?  All float glass has two sides.  The underneath where it rides the molten tin down the glass ribbon.  Also the side that faces up and is only in contact with air.  It is in fact interesting to note that in the IWCA's collection of scratched glass with “rough surfaces",  the tin side was the rough side.  Also, the tin side was more easily scratched.  Should this surprise us? Is it possible that the tin side of float glass can develop a random roughness?  But exactly how?

A Closer Look at the Tin Side

To begin to understand this, I direct your attention to the paper “Statistical Analysis of the Metrological Properties of Float Glass” by Brian W. Yates and Alan M. Duffy.  This paper speaks of a “surface roughness” that develops on the tin side of float glass and reports “It can be seen that the overall tin side surface roughness average is indeed rougher on average than the air side”. The conclusion reads: “Statistically significant differences were found between the tin and air side surface roughness values for both untreated and acid treated, with the tin side being significantly rougher than the air side.”  Is there a definite  link between the rough tin side of some glass surfaces and surface scratching? Does post production heat treatment of glass exacerbate the roughness of some glass surfaces?  These questions will be closely examined as you are about to see.

Real Science

Armed with this knowledge, questions and the collection of scratched glass samples, the IWCA has embarked on the first of its kind scientific research during the summer of 2016. Dr. Paul Duffer has greatly expended his time and energy leading the way for the IWCA to participate in a special research program at the world class Department of Materials Science and Engineering at Pennsylvania State University. Professor Seong Kim, phd  is quite dedicated to materials science and has much experience with glass surface studies. He has been and will continue to oversee the IWCA research of scratched glass at Penn State.  Already we have learned so much about the real science of float glass surfaces.  But this is only the beginning.
Where Will This Take Us?

The IWCA is dedicated to helping window cleaners better understand the glass surfaces that all of us work on every day of the week! Armed with knowledge as an industry we can develop much more effective, efficient, and safe cleaning methods.  Such advanced knowledge will result in the very best products, and practices that will assist us in maintaining the integrity and beauty of glass, reduce possible damage, and adequately protect ourselves legally should aggressive cleaning techniques and restoration become necessary on a job site.

The GANA/IWCA Joint Bulletin
GANA TD 03­1003 (Reapproved 2010)

Construction Site Protection and Maintenance of Architectural Glass
Steps Must Be Taken to Avoid Permanent Damage to Glass

This bulletin focuses on the fact that attention and blame should be put on general contractors for not protecting the glass during the construction process.  It states that, "The complex nature of construction projects and site management requires well‐planned and executed material delivery and storage.".  Regarding storage the bulletin states that the duration of site storage must be minimized.  Also storage should be under roof to avoid direct rain and water runoff.  Further adequate ventilation must be maintained to prevent damage from condensation.  Deposits from concrete or masonry runoff can cause hard water spots during storage.  It discusses glass surface or edge damage as being the result of inadequate on‐site protection and ill‐advised or vulnerable storage locations, also exposure to other trades.  Stating also that, "Deep  surface  scratches,  contact  by  hot  weld‐splatter  and  edge  damage  threaten  the  structural integrity of glass and may require glass replacement.  Surface contact with harmful materials will require  prompt  cleaning by  professional window  cleaners, such  as members  of  the  International Window Cleaners Association (IWCA).".  It is further stated that it is the responsibility of the general contractor to educate all of the other trades, regarding glass protection during storage and installation.  For this reason the glass in storage should be inspected daily.  There is much information in this bulletin which expertly identifies the chemical and physical damage that can result during storage and how to determine the cause of this damage. 
Protection Options During Construction

The very first thing that must be addressed is the fact that glass with nano-scale roughness is exposed to scratching during storage and every other phase of the construction process.  Glass with this type of surface must first be identified.  We are the very best choice for the general contractors to do this.  Then once it has been identified adequate steps must be taken to protect it from scratching and other surface damage.  There are temporary self clinging films that can be applied prior to storage which can be quickly and easily removed after construction.  There are also paint on protective plastic coatings that can be pealed off too.  When these are contaminated by construction debris such as concrete splatter, hard water spots, silicone caulk, stucco runoff, paint, wood stain, or other deposits;... such will come off with a simple pull.  There are other wipe on completely transparent products/sealants that are intended to be much more permanent and everlasting.  They are not intended to be removed.  Certain ones even offer a measure of scratch protection.  However just use caution, as the brush on temporary peal off films will actually stick to these permanent sealants.  So you will want to apply the permanent sealants after first pealing off any temporary brush on films.  Protection during construction, (from glass storage to the finished construction project), is an aditional service that window cleaners should offer.  Especially if we are doing post construction work.  It will be necessary to first become familiar with this new technology of glass protection, the various products available, and then educate the general contractors we work for.
The IWCA and the Glass Committee is your best defense against the ignorance surrounding the scratched glass issue.  It is also your best source of information that will help you to earn greater respect from your customers and a much higher profit margin.  Join the cause today.
Written By Paul West and Henry Grover Jr.
Members of the Glass Committee of the IWCA

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Polishing Glass with the Gyro Wheel and Pure Compounds

There are many different gel like hard water spot removers on the open market.  But most of them are not true polishing compounds.  They are not pure blends of high tech optical grade polishing  powders.  It is because of this that the application method along with the results obtained are both quite different.  Polishing optical glass surfaces is both an art and a science.  As a case in point you will notice the optical fibers in the picture at the upper right.  The ends of these fibers must be perfectly polished.  To do this polycrystalline diamond lapping films are used.  Very special procedures are also used in production polishing of optical lenses and substrates for mirrors.  Then why should our technique be any different for removing mineral deposits from windows?  If we are so focused on perfection when we work our squeegees, why shouldn’t we also be just as determined to recreate the very best surface for our customers?

The first thing we should focus on is the flatness of what is called in the industry;...the lap.  There are many different materials including pitch and even wood.  Along with some rather esoteric laps that I will be researching for the WCR.  But right now in this letter lets look at hard felt.  I have chosen a flat ring with an outside diameter of six inches, an inside diameter of four, and a thickness of 1/4 inch.  It has a pressure sensitive adhesive on one side so it can be easily fixed to the Gyro Wheel seen here in the picture.  This wheel can be di
rectly connected to most any drill motor.  It has a universal joint built into the shaft that allows for a twelve degree variance.  With a fail safe collar surrounding it.  I like to start my speed at about 1,000 rpms.  Faster speeds will remove stains even quicker.  But you must keep on testing the surface to make sure the glass doesn’t  get too hot. 

First you should clean the window with exact precision.  Making sure there aren’t any sand like particles remaining.  Next wet it well with a clean soapy solution or a liquid designed for polishing glass.  Next put about six or more drops of compound on the bottom of the hard felt ring.  Then put the ring up against the window and start the drill motor.  A variable drill motor that runs between 0 and 3,000 is a good choice.   You will want to move around a two by two foot area.  Give it about a minute, then squeegee off the slurry.  Examine the surface to see if all of the spots have been removed.  You might feel the dry surface with a dry fingertip.  But the best way to determine if all of the deposits have been removed is to fog the new surface with either a fogger or your own breath if possible.  If there are any deposits remaining you will see their appearance in the fog.  If you have indeed created a brand new surface without any deposits remaining, the fog will ‘sheet over’ showing absolutely nothing.

With the angle of variance that the wheel allows, you will be able to easily keep the hard felt lapping ring totally flat on the glass the entire time you are polishing.  This will maximize the overall effectiveness of the compound and the system.  It will also help in reducing the operators stress making the work much more endurable.

This is just the beginning.  I will be looking into different laps and building many different pure polishing compounds.  That will be based not just on high tech powders, but also different suspensions.  The reason for this is that polishing is not just a physical process but also a chemical one.  In fact it is for this very reason that some particles have been chemically ‘functionalized’. 

Written by Henry Grover Jr.

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A Technical Explanation of Organic Solvents and the Green Terpene

Organic solvents are simply put hydrocarbon liquids that break up and dissolve other hydrocarbon based substances.  Some other elements other than carbon and hydrogen that OS molecules use are oxygen, chlorine, and nitrogen.  The OS molecules will move in and around  surrounding the molecules of the solute (that which is being dissolved) forming a solution. 

Now there are two very basic types of organic solvents;...polar and nonpolar.  OS liquids with a dielectric constant of less than 15 are said to be nonpolar.  Those with a very high dielectric constant are said to be polar.  This is important to us because it helps us to choose the best OS for the job.  Since like dissolves like, deposits that are very polar require very polar solvents to dissolve them.  The opposite is also true.  Most oils and waxes are very nonpolar.  Hence they require very nonpolar liquids such as hexane to dissolve them.  It follows from this that it is important to determine exactly what the polarity of the substance being removed is.  Then match that with the right OS with the same polarity.  A quick search on the net will reveal the dielectric constant, and therefore the polarity of both the substance to be removed and the OS needed to dissolve it. 

There are also protic and aprotic polar solvents.  Protic solvents work well with negatively charged solutes.  While aprotic solvents work well with positively charged solutes.  The solute being the substance in need of being removed/ dissolved.  You can find quick lists of protics and aprotics on the net.  Remember any OS with a dielectric constant in excess of 15 is polar.  Less than 15 is nonpolar. 

Some other properties we might want to look at are melting point, boiling point, autoignition temperature, and water solubility/miscibility.  The melting point is also the temperature at which the OS will become rigid or form a solid.  Which is difficult if not impossible to work with.  So a melting point in excess of 0 Fahrenheit is obviously necessary.  The boiling point is the temperature at which the OS becomes a vapor or gas.  Since there are times we are working on very hot glass it would be good to have an OS with a relatively high boiling point. Next a solvent with a very high autoignition 
temperature will not automatically ignite without notice.  If our OS were soluble or easily emulsified in water it will be easy to remove from the window once it has done its job. 

Lets next take a look at an OS that comes from the rind of the orange.  It is gaining much attention in the cleaning industry because it is relatively nontoxic yet powerful enough to dissolve many hydrocarbon based substances.  It has been called the green terpene and is d-Limonene (a monoterpene).  The chemical formula is C10 H16.  It has a boiling point of 349 Fahrenheit.  A melting point of –140 Fahrenheit.  A flashpoint of 110 degrees.  Autoignition temp of 458.  Although it is not soluble/miscible in water it can be blended with certain synthetic detergents so that it is easily emulsified by water.  The dielectric constant is 2.3 as it is an aprotic nonpolar solvent.  It is used as a paint stripper, and a cleaner.  It is actually possible to add it directly to water if it has been emulsified with the right surfactants, to effect a cleaning solution.  Just a few ounces per gallon of water will work. 

There is a product that is based on  93% dLimonene and a couple of different surfactants for emulsification.  It is easy to remove from glass with any cleaning solution.  And is very effective at dissolving most non polar aprotic organics.  It will soften water based paints making them very easy to remove with a razor.  Just apply the product, wait a few minutes, and blade the paint away.  It also softens fully cured silicone caulk (this is not a hydrocarbon but is rather based on an Si-O repeater backbone chain).  It will soften fully cured oil based paints.  And works on many other hydrocarbons.  It is even possible to add it to your cleaning solution at a concentration of about four ounces to a gallon of water.  Or a one to sixteen ratio.   

There is also a urea plastic media/compositional abrasive with a particle size between 200 to 400 microns.  It has a good sharp cut and is softer than glass.  So it cannot scratch glass but will chew through silicone caulk and paint.  When coupled with the Green Terpene or another very powerful solvent it is much more effective at removing deposits such as cured silicone caulk, paint, or wood stain.

Written by Henry Grover Jr

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Wednesday, January 9, 2019

Big News From The Glass Committee

I just received this update from Paul West about three events that will be taking place that will have a direct effect on all window cleaners.  As you might know the IWCA has been directly involved now with NGA/GANA regarding scientific studies.  This lab work has turned out some really fascinating discoveries.  Headway is being made and I think you will find the following as hard evidence of that fact.  Read on.

1) Annual NGA/GANA Conference - January 22-24, 2019. The IWCA has been invited to do a presentation on 01/24 to all the Glass Fabricators at their annual convention. The seminar will be dedicated to the history of IWCA/GANA relations and present future cooperation. The one hour presentation will discuss joint bulletins, industry relations and research - along with paving the way for future cooperative efforts. Dr Paul Duffer will present and both Jeff Klass and President Butch Chapman will attend. 
Here is link:

2) Glass Expo Northeast - Thursday March 28, 2019. Dr Paul Duffer is scheduled to present the “Unique Vulnerabilities of Glass at Construction Sites” seminar for official AIA Continuing Education credit.

3) International Congress on Glass - Boston, MA in June 2019. Professor Seong Kim, lead researcher at PennState, has been invited to do a presentation. It will be called “Glass for Buildings and Transportation.” He has asked to include the results of IWCA funded research and how it impacts glass in buildings, window cleaners, architects, and general contractors.

These three events represent major exposure for the window cleaning industry and the IWCA to thousands of parties interested in glass including but not limited to: glass fabricators, glaziers, tempering companies, equipment companies, architects, designers, and general contractors. A huge step forward in getting our message out to a massive amount of people. Very exciting!

Paul West
Kohala Window Cleaning LLC
808.885.7600 (O)
808.443.3833 (M)

Information presented by Henry Grover Jr.

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For four years now I have been working on this blog (aprox 132 posts), written articles in the AWC, WCM, and the EClean, and met and conferred with many amazing people who own and work in the window cleaning industry.  My research goes back to the time when I began cleaning windows which was the spring of 1981 according to the best of my memory.  It was the very late 80s and early 90s when I discovered Rich Fabry and the AWC and started writing for it.  Some years after that I gave a couple of seminars for the brand new IWCA.  Met all of our industry icons of that time.  Had the opportunity to get to know and work with the Unger family.  Also I had the opportunity of getting to know other industry leaders through consulting work on some very famous buildings.  It has been a long time for some.  But it seems like a short time to me.

Here are some pictures that were taken from one of my many visits a long time ago.  It was one of my most enjoyable journeys.  I met many very interesting and amazing people.

At that time I didn't even have a cell phone.  Just a pager.  A few years later I got a flip phone.  There is absolutely no comparison between old tech and current tech.

Nonetheless I digress.  Let me say that it has been a very interesting journey.  Through my writings over the last four years I know that many people have been "mining" for information that they can use to develop products.  And some have been developed.  Twenty five years ago I put one manufacturer onto a certain chemistry that was being used to seal glass.  Which was ultimately abandoned.  But that chemistry was adopted by one of our industry icons who created a product from it.  It is still doing well on the market.  

I have experimented with many newsletters over the years, none of which ever lasted more than a year.  The last one call the Glass Smart Insider only lasted a month.  I tried selling products.  Unfortunately that did not work out as most of the packages were either stolen or were destroyed in transit.  Distributors absolutely earn their wages!  And no one else is very interested in picking up any of the "products" I have developed whether they be chemical or mechanical.  

I am very pleased that Chris and Alex Lambrinides have allowed me to continue with whatever ideas I come up with on their Community Forum.  I have met so many great people here.  We truly are a very innovative and honest group.  Window Cleaning has given me the money to pay my bills and the freedom to live my life.  Being able to reach out to others has only enriched my experience.

Very recently Paul West invited me to participate with the IWCA Glass Committee.  This has become one of the most fascinating endeavors of my work.  Having the opportunity to study very technical reports from a real science lab has been very satisfying.  I am also very grateful to Mike Draper for allowing me to join with Paul in writing a series in the AWC over the last year.  It has been a real treat.  And I hope it has benefited many.  Although my priorities have become very refined recently and I am not able to continue writing for any outside industry publications.  Nonetheless I am sure you will find the information presented in this blog very useful.  I will only be writing on the WCR Forum and this blog.  Chemical names and formulas will be given freely.  Which will make it most impossible to develop products from.  I do suppose it might be possible for manufacturers to mine my writings and decide to use certain chems in a formula they develop.  Then keep the actual name off their SDS by not using more than 1% of the chem.  Or some other trick.  I know right now they will add water and not mention it other than as a "proprietary" ingredient.  This just confuses people.  So that other manufacturers will not know exactly what the formula is.  This way they cannot "steal" the formula, and change the product name and label.  The end user doesn't care of course if they get a good product for a reasonable price.

So there will be no thieves.  No manufacturer will care to copy whatever I have developed and will develop because all of the information will be out there.  You will find it here on this blog and or on the WCR Community Forum.  I will not be working with any manufacturer on any product.  My love and focus will always be on custom products, chemistry, glass science, and glass Surface Maintenance And Restoration Technology (S.M.A.R.T.)

Written by Henry Grover Jr.

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Wednesday, December 5, 2018

Solving the Problem of Hydrophobic Glass for WFP Work

As I have explained in previous writings there are three steps to solving the problem of hydrophobic (water hating) glass. The first part involves "deep cleaning" of the window.  In other words removing all hydrocarbon pollution which is hydrophobic.  There are several different ways this can be done.  I am currently researching the most efficient but safe way to do this.  The products and technique used to do this will be made known in the Insider weekly e-letter.  The second step involves treating the surface with some type of a hydrophylic film, crosslinked or not.  The longer that it lasts the better.  We need to seal glass that has been deep cleaned.  Such deep cleaning makes glass very sensitive to scratching.  So it is important to choose a hydrophylic sealant that makes glass that is scratch sensitive, scratch resistant.  This type of sealant also helps to maintain the hydrophylic property of deep cleaned surfaces. This sealant will also help the pure water rinse to sheet over the entire window and drain down from top to bottom leaving no spots.  The third step includes using a super-wetting surfactant/soap that will effectively sheet over the entire surface effectively cleaning it.  Very little of this type of syn-det is necessary.  But we need one that is based on a silicon chemistry.  Not silicone but silicon.  It also should be an anionic.  Super wetting syn-dets will effectively sheet even Rain X coatings.  Which is truly amazing.  And do it at extremely low concentrations.  But remember the final rinse will always be with pure water untainted by any soap.  Which needs to sheet, not bead up.  So the first two steps are critically important.  This would be deep cleaning and sealing.  

Both the products and techniques to accomplish all of this will be given in the Glass Smart Insider over the months.  This is a monthly e-letter which is available by email as a PDF attachment.  The subscription price is ten bux per month.  Or 20% off as a half year subscription.  Sent as a Paypal request by email.

Written by Henry Grover Jr.

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To subscribe to the Glass Smart Insider just send me an email.

Tuesday, November 27, 2018

Glass Smart Insider; Giving You The Competitive Edge

I am sure every window cleaner that does WFP work knows how annoying hydrophobic glass is.  It is also known how much less time it takes to clean a hydrophylic window with a WFP.  What is not known however is what is the easiest way to convert a hydrophobic window to a hydrophylic?  What really is the reason why some windows are hydrophobic and some are not?  The technology of hydrophylic glass surfaces will be explained in the Insider.  New products and chemicals will be identified.  You will only hear about them in the Insider.  I am waiting on a sample chemical right now.  When I know about it so will you.

Another technology I am currently working on is the development of a silicon carbide compound for grinding (NOT polishing) glass.  This will be used to remove etched surfaces and heavy mineral deposits leaving a perfectly smooth white translucent haze which can be removed with a cerium oxide in minutes.  So a two step restoration procedure.  Diamond does have its place as I have explained in previous posts.  But there are distinct differences between diamond and silicon carbide which gives the latter a decided advantage.  Again I am waiting on a sample in the mail that was just sent out this week.

Now I know I have had difficulty with time because of being in and out of the hospital.  But I have advanced to the production of my first line of Slow Release Coated pads.  Which slowly release a water activated polish for removing light mineral deposits or converting hydrophobic to hydrophylic.  This Slow Release technology will be completely explained in the Insider.  All of the ingredients will be identified and how to put them together.  Along with how to use the pads.

Further there is much to do in understanding why certain windows are easy to scratch while others are not.  How is it that we can inadvertently change surfaces so they become scratch sensitive?  Also what products are the most effective at making surfaces scratch resistant?

The biggest problem in taking on a twenty or forty thousand dollar stain removal job is being able to guaranty an easy and inexpensive maintenance of the windows once they have been restored.  The only way to do this is with the use of a glass sealant.  Should this be a hydrophobic or a hydrophylic sealant?  Also how do we know that the product we chose will give adequate protection?  This is another hot topic that the Insider will address.

These and many other subjects will be addressed in the Insider.  You can sponsor this work at only 10 dollars per issue monthly, or as a half year subscription at 20 percent off.  So a half year sub at 48.

I have started writing in December 2018.  

Written by Henry Grover Jr.

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Sunday, November 25, 2018

Fantastic Profits in Surface Testing and Protection

3D Optical Microscope Measurement of a Textured Glass Surface

The Glass Smart Insider will help you learn how to test glass for scratch sensitivity and how to protect glass from scratching.  This is a brand new science for window cleaners.  It is a very much needed service, and is potentially very profitable.  According to the Wikipedia metrology is, "the science of measurement, embracing both experimental and theoretical determinations at at any level of uncertainty in any field of science and technology.".  What we are concerned with in this article is the science of measuring the physical characteristics in 3D of the surface of window glass.  So 3D surface metrology.  Why?  Simply because this measurement will tell us exactly how sensitive any window is to scratching.  You see it is in fact the microscopic and possibly even the nanoscopic roughness of the surface that determines how easy windows will scratch.  I have proven this by simply polishing one half of a brand new mirror plate with a cerium oxide slurry and a felt pad.  This is the typical procedure that window cleaners will use to remove hard water spots.  Then dragging a broken piece of glass from one edge to the other.  The half that has been polished will show a perfect scratch.  The other half will show some scratching but not much.  This can also be done with acids that etch glass such as hydrofluoric and sulfuric.  To desensitize a polished surface it is necessary to treat it with a long lasting sealant.  Not one that is degraded by UVC in only a month.

Filmetrics Logo

What is fascinating about this condition is that it does exist on brand new float glass.  Obviously something is happening during the manufacturing process to alter the microscopic roughness.  Right now we do not know what that is.  But we have learned that it can be created both mechanically and chemically.  In other words it can be a mechano-chemical process.  We have also learned that this type of surface can be changed.  It can be made scratch resistant.  That kind of technology opens up a brand new market for window cleaners.  Especially on post construction sites.  We can first test glass to learn which glass is scratch sensitive.  Then we can offer protection.  Both at a cost.  Which will be explained in the Glass Smart Insider.

Written by Henry Grover Jr.

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Friday, November 16, 2018

Gaining the Competitive Edge with Diamond Products

Products that are based on microscopic and even nanoscopic diamond particles can easily give you a very strong edge over your competition!  The real key to accomplishing this is twofold.  First you must know precisely what diamond products to use for what purpose.  Second you must find a way to use this technology in your marketing.  The first is quite obvious.  Diamond can create serious problems if not used correctly, or simply be ineffective.  As for using this technology in your marketing efforts you will have to focus on the real benefits to your potential customers.  Also your existing customers because they will help you with publicity.  

Diamond particles have been used in colloidal suspensions, compounds, coated films, and loaded metals and ceramics.  Probably the most common type of product available that window cleaners are familiar with is the colloidal suspension.  There is a product out now called Diamond Magic which uses a liquid suspension of diamond particles.  If you look at the SDS for this product you might notice that the amount of diamond by weight compared to the total volume is rather small.  This is likely for two reasons.  First diamond powders are not inexpensive.  I remember twenty years ago paying fifty United States Dollars (USD) for about a tablespoonful!  Surprisingly the price is approximately the same today.  I know this blog goes into many countries worldwide so your supplier might charge different.  The bottom line here is if you are going to develop a glass restoration product based on a diamond powder you will have to multiply your total cost by a factor of 4.5 to 6 to get the end retail price in order to make a profit.  Second it is not necessary most times to use very much diamond to get a certain desired result.  In fact along this line of thinking water is one of the best ways to lubricate diamond products. So at times less is more.  I always say check your surface.  Checking in the direct sun is always best.  There are always variables involved here.  One of the most notable is that we are not working in a facility, nor are we working in a lab.  We are working with surfaces that are completely unknown.  When polishing a glass surface that has been covered with hard water spots or mineral deposits, you really have no clue exactly what they are made of.  You don't know what the size of the mineral crystal structure is either.  Also you don't know how the polishing product you are using is going to react with the deposits you are attempting to remove.  This is a great deal of unknown factors here.  So as my friend and glass restoration guru Marc Tanner puts it, every job is different!  We cannot take much advice from the lab techs because they do NOT work in the field with us.  We are the scientists.  We are the field techs.

Another type of diamond product are the compounds.  Now compounds are very thick blends of diamond powders and suspending agents.  These products use way more diamond powder.  Even as much as sixty percent.  They are very effective at cutting glass when using the correct technique.  Even polishing compounds will cut through glass very effectively.  Although it is rather easy to leave swirl marks that are visible only in the direct sun.  For some of the different reasons mentioned above.  I remember one time tackling a restoration job that had about 1,974 very small windows that were badly stained from a cleaning product based on sodium metasilicate and sodium carbonate.  I tried a small rotary machine with a hard felt pad and a great diamond compound;...but it left visible scratching.  It was very effective at clearing the stain, which no other polishing product would.  I even tried some of the very bad acid based products out there that I would never do a job with;...just as a test.  They also would not touch the stain.  The only way I could remove the stain and leave no scratches from the diamond compound, was to rub it out by hand using Bounty paper towels.  

Here is the most efficient way to use diamond compounds on large area glass plates.  You will need a rotary machine that remains flat on the glass at all times.  I have included a picture here of a wheel that I had built special.  You will notice the 3/8 shaft is tilted slightly to the left.  That is because there is a universal joint added to the inside which the shaft is connected to.  The holes in the wheel gives it lightweight.  It is made from mag/aluminum.  And the center cylinder allows for safety.  There is only a 12 degree variation in movement of the shaft.  Any hard felt pad can be glued to the bottom.

The easiest way to use such a tool is with a rotary drill motor.  First clean the window.  Then apply some clean soapy water to the window.  Next apply just three or four drops of diamond compound to the hard felt pad.  Now apply the pad to the window and pull the trigger.  It is always best to start out slow and gain speed.  I would first try removing the spots as slow as possible.  You can get a zero to three thousand rpm drill motor.  Or if you decide to get a much more powerful grinder which is much heavier you can also get a variable.  But will have to adapt the shaft to the grinder.  Whatever wheel you have built or purchase.

Here is an old video I made about five years ago showing how this concept actually works.  I made up what I call a slow release felt disk based on a cerium oxide.  Currently I am still working the bugs out of a microcrystalline silica slow release pad.  Such a pad would eliminate the need for continually applying drops.  But you would need a trigger to apply soapy water.  No matter whether you use compound drops or a slow release pad, there is the definite advantage of not needing to clean up a huge mess.  You will be able to minimize the amount of product you use.  And squeegee from time to time to check your work.  Here is the video.

Archer USA 4 in. #3000 Grit Wet Diamond Polishing Pad for StoneNow this is just the very beginning of this technology.  Check out this picture.  
This pad/wheel is used with pure water for polishing granite counter tops to a high shine.  It is essentially a plastic medium loaded with diamond or silicon carbide particles.  Over time it is worn down and is thrown away.  But is capable of doing many square feet.  One time I had a bank of windows that were seriously stained by hard water spots.  It was dark glass and so was the most difficult surface to restore.  None of the compounds I had would work.  Again not even the acids would work.  So I picked up a fifty dollar diamond disk and spun it with nothing but pure water.  In a single minute it knocked off the stains perfectly!  The only problem was it left very fine scratches all over the window.  These could have been removed with a cerium polishing compound.  But I was looking for a simple single step answer.  It is likely that any scratches of this type left on a granite top would not be easy to see.  But when working on glass anything jumps right out at you.  Especially in the direct sunlight.

Now there are thousands of different products out there.  If you look at the left column of this blog you will be able to pick out at least three or four companies that sell diamond products.  A couple specialize in just diamond products.  But how do you know which ones to buy, and how to use them?  That is what I have decided to focus on in my very latest newsletter called the Glass Smart Insider.  Still focused on the most innovative technology for the window cleaning industry.  There is so much out there.  So much to learn.  And so much to apply.  I am seriously looking for sponsors to help me with the time and expense of furthering this technology.  I am asking only ten USDollars per week for this very simple grassroots electronic newsletter.  It is a very pain letter I am sending out by email. Available as a subscription only.  But you can pay as we go.  No need to pay in advance.  You can pay once a week if you want.  I have set up a Pay Pal account if this is easier for you.  And will be exploring other means for those living in other Countries. But if you just want to send a check that is another way.  I just have not set up with credit/debit cards yet.

I am looking forward to meeting and getting to know those who have been reading this blog for the last several years.  I am almost at 100,000 views.  And am hoping it has already made a difference in your business.


Wednesday, November 14, 2018

November 2018 Glass Smart Bulletin

The Destructive Power of Acids

Unfortunately most building owners, property maintenance managers, and even window cleaners are not aware of the destructive power of acids.  The general opinion is that windows cannot be harmed by acids.  That even when windows become seriously stained by hard water as is shown here in these two pictures, all that is required is a quick "acid wash".

Little do they know that chemicals such as hydrofluoric, sulfuric, and ammoniumbifluoride  have a detrimental effect on the window surface;...every single time!    

Acids and Dark Glass

Actually there are an assortment of acids and alkalies that react with glass surfaces. Hydrofluoric acid however is probably the most common.  This is the one which has been favored by the window cleaning industry for many years.  It has been added to so called professional glass restoration products.  Companies have even used it pure in much higher concentrations.  The destruction caused by this acid can be seen all over the world in every country.  Based on what I have personally seen in the field it has had the greatest effect on dark glass.  That is glass that is tinted with different metal oxides all the way through from the inner surface to the outer surface.  The full thickness in other words.  I believe that dark glass is most easily "dissolved" by hydrofluoric (HF) acid.  HF will "eat away" at the surface leaving behind clear impressions of hard water spots.  This causes a type of "orange peal" effect.  If used to remove long drips of a concrete sealant this results in a "banding" effect.  Any light scratches that might have been covered over and hidden by newly formed hard water spots are fully revealed and become magnified fifty times.  On occasions these are difficult to see unless the sun is shining directly on the glass.  So they become visible when the sun moves around to that side of the building or comes up the next day.  It is also possible that the surface could take on a patchy/cloudy etch.  Again this could be rather light or very intense depending on different conditions present at the time the acid was used.  One other effect I have not wrote about yet involves a change in both the chemistry and the physical properties in the glass surface.  When glass is exposed to HF it becomes very prone to scratching.  So glass that was previously very smooth and resistant to scratches now becomes very rough and easy to scratch.  Making it that much more difficult to maintain over the course of its life.

Acids and Clear Glass

All of the effects mentioned above also apply to clear glass.  Just not as intense in my opinion.  Although it is true that both hard and soft low e coatings are much more frequently used these days on the first surface of clear glass.  The trend also is for these coatings to be very transparent.  So it is very difficult to know they are even there.  You would have to test the surface with a device or some other way to determine if it had a coating. Companies have come up with coatings that are supposed to have photoreactive and even photovoltaic properties.  Any of these high tech coatings would be destroyed by the first time use of these different acids such as and especially HF.   I have include below a picture of the kind of damage that is caused by the use of HF on an old coating from PPG called Solar Cool Silver.  This coating was literally stripped off by HF and is now impossible to repair.  The windows on this building have been permanently destroyed.

This Bulletin is published in this blog for the general public.  Not that this information is necessarily known by all window cleaners.  Because it is unfortunately not.  The sad truth is that there are thousands of window cleaners that do not know and or simply do not accept this information.  The ability to make a quick buck coupled with the desire of the building owner to save thousands of dollars, has driven the widespread use of acid.  The cost of properly and correctly restoring a window can easily be ten times the cost of clearing it with an acid such as HF.  The risk of losing a window here and there or even all of the windows is seen as the price that must be paid to save all that money.  This is rather faulty reasoning however.  For if you must replace the windows because of acid use the stains will still return.  The old and or new windows must be sealed with the correct product and then the windows must be properly maintained.  The ultimate cost of window replacement could be very expensive.  Much more then having a proper restoration performed or certainly much more than a quick acid wash.  If you are looking for more information on this subject just send an email to

Written by Henry Grover Jr.

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Monday, September 3, 2018

Introducing Jared of Aztec Innovation

Everyone talks about developing products as if this was some kind of a ticket to the easy life.  But the reality is it is not as easy as we think.  It truly is another business system that has to be followed according to certain rules.  One of the greatest innovators and inventors we have had in our industry was Henry Unger.  And we have had many.  He told me once that he had over fifty patents.  He also told me the best way to do this was to work on only one product at a time.  To focus.  Of course there is so much more.  I have learned a great deal from people like him.  Listen to Jared talk about his process.

Written by Henry Grover Jr.
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Monday, August 27, 2018

Stain Removal;...Dark Glass, Clear Glass, & Low E

If the stain has the same exact chemistry will it come off dark glass just as easy or hard as clear or low e coated?  Absolutely not.  How do I know this with such unwavering certainty?  Simply put because I have a building that has both dark glass and windows with a low e surface.  This building is covered with mineral deposits from the same exact water source.  So the stains are identical.  When trying to remove the stains by what I call the "hand test" using a simple compound based on a microcrystalline silica, I was able to easily remove the spots/stains from the low e pyrolytic surface, but not the dark tinted glass.  The stains on the dark glass would not budge at all by hand.  When using a machine it became possible to remove them but not without much effort.  From other testing on buildings that had both clear glass and dark glass I know that stains on dark glass are much more difficult to remove then stains on clear glass.  Although stains on low e coated windows are the easiest to remove of all.  So it goes in this order from the most difficult to remove to the least difficult to remove;...dark glass, clear glass, and low e coated glass.

I have created my first beta SRC pad based on an optical microcrystalline silica.  I made it for light stains on clear and low e surfaces.  Not for dark tinted glass.  Even the "lightest" stains on dark glass can be exceptionally difficult to remove.  I am guessing this has something to do with the possibility that the surface of dark glass goes through a reaction with the water and literally breaks down in solution.  Through some rather simple testing I was able to prove that water spots are able to etch dark glass surfaces removing some of the glass.  This leaves a transparent/clear "imprint" of each spot on the surface.  Such an anomaly appears not to happen on clear glass or low e pyrolytic surfaces.  Although it has been conjectured that "pinholes" can form on low e pyrolytic coatings when an excessive amount of mineral deposits are allowed to develop on this type of window and remain for some time.  Either way stains should never be allowed to form on windows and remain.  Especially on windows with dark glass owing to the amount of excessive labor that is necessary to effectively remove them.

Written by Henry Grover Jr.

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Saturday, August 25, 2018

Avoid Lawsuits with Scratch Testing!

What scratches and when?
This is usually a total crap shoot.  A throw of the dice.  We might win or we might lose.  Did you know there is a way to dramatically increase the odds in our favor?  It involves a very simple test that almost no window cleaner has ever performed.  Let me explain.

Testing Conditions.

I have developed many very simple tests over the years that anyone can do.  This one involves the use of a one by one foot square mirror.  I choose mirror plate because it is very easy to get.  Also mirror shows up the slightest blemish.  At times I will take the "test plate" into a totally dark room and shine a flashlight at the surface at a 45 degree angle.  Then look straight down the beam of light.  This shows up every imperfection.

Tools, compounds, and machines.
So I take a brand new mirror and polish the entire surface with a cerium oxide (optical quality).  It should look perfectly fine without any imperfections.  The best way to do this is with a rectangular piece of soft felt glued to the based of a random oscillating buffer of about 10,000 opms.  That is oscillations per minute.  

Image result for rectangular random oscillating sander

You will know that you have set up the surface correctly because when you rinse it under the tap pure water it will sheet evenly over the entire plate.  It will be so hydrophylic (water loving) that it will appear to be dry.  Now squeegee off the water so it is dry.  You will notice that the surface is now quite rough if you pass a dry fingertip across it.
What surfaces are way easy to scratch?

Rough surfaces are extremely easy to scratch.  Items that would hardly ever scratch a smooth plate of glass will absolutely scratch a rough surface.  This test plate is great for testing metal wool, synthetic wool, and many other things.  While it is not absolutely fool proof, it will help out tremendously at revealing what items are very prone to scratching. 

Adding Glass Etchants to the Test.

Another additional feature of this test involves the use of hydrofluoric or sulfuric acid.  Sulfuric is easy to get from an auto parts store because it is battery acid.  So very dangerous.  Hydrofluoric can be obtained by purchasing so called glass restoration products based on a little over 1% HF.  One product called Crystal Clear 550 has this chemical.  Again it is a very dangerous chemical so be very careful  I have posted some very educational videos in this blog.  You can search the blog with the search bar.  When testing I will try to scratch and area.  Then treat only half that area with either acid.  HF works best.  Take the test plate into a very dark room and look at the area that was tested with a bright flashlight.  The acid will have magnified any blemishes 25 times over making them very visible.  You will also be able to compare all three surfaces.  The roughened surface untouched.  The roughened surface tested with the product in question.  Also the roughened surface tested with both the product in question and the acid applied afterward to magnify and blemishes.

Minimizing the Likelihood of a Lawsuit.
If you know what most likely is going to scratch and what most likely is not going to scratch you are most like going to be able to avert any lawsuits.  This is indeed our goal as many times we are faced with removing various things such as construction debris but do not want to do damage to the surface.  Especially if it is brand new glass.  Being an older house no one seems to care that much.  But brand new homes always come under the responsibility of whoever is the very first one to clean them.

Written by Henry Grover Jr.

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