BMW Car magazine - February 2007

What's involved.... in Window Tinting?

Window tinting. It has a certain reputation: it smacks of pitch-black pimp rides, of bubbled and blistered reflective film, of over-loud music and Kevved-up hatchbacks. Yet the world's leading tint firm, Pentagon GlassTech, has a client list that reads like a Who's Who of Britain. Co-founder and MD Peter Mukherjee tells us that pop stars, VIPs and sports heroes all get the treatment at Pentagon's Acton HQ. Moreover, explains Peter, Pentagon carries out work for leading prestige motor manufacturers in the local area such as Land Rover, Mercedes and Aston Martin, which have Point of Sale for the product within their dealerships. In fact, trade work makes up around 60 per cent of the company's business.

Pentagon decided a long time ago to try and establish itself at the upper boundary of the industry, offering top quality workmanship, cutting edge materials and a varied range of products.

There is another aspect to take into consideration these days: the law. As of 2004 the law regarding visibility from cars was amended to include window tints. Pentagon was already a champion of lighter shades of window tinting and well aware of the need for safety within the industry.

The driver's view must not be impeded and the law specifies 70 per cent visible light transmission (VLT) on the forward windows. Pentagon pretty much exclusively only tints windows backwards of the B-pillar (some clients insist on other specifications and Pentagon makes sure that they know the law). Apparently the police are fairly tolerant of levels down to 50 per cent VLF but customers are recommended to leave the front side and windscreen glass untinted.

There is no limit for the level of tint backwards of the B-pillar, but the company doesn't recommend too dark a tint in the interests of safety. Their range starts from a Light Smoke (43 per cent VLT) through Smoke, Midnight and Limousine. The current trend is for the lighter shades.

As well as being the best timers in the business, Pentagon also created a new product in 2000 called SupaGlass. Originally developed in conjunction with Land Rover, SupaGlass is a laminate layer 300 microns thick fitted to the inside of the glass (compared to the tint film at 40-50 microns) that massively increases the glass's strength. Pentagon claims it resists around 90 per cent of car crime –particularly opportunist theft. Its resistance to breaking also makes it an ideal anti car-jacking product. As an added benefit it stops the glass shattering in an accident, protecting the occupants, yet while it is tough from the outside it can easily be pushed out from within.

Unlike similar competitor products, the SupaGlass is fitted to the glass when it is removed from the door (not just filling the hole) and is therefore attached to the runners when the window is refitted. This makes it extremely strong and damage resistant. The costs vary from client to client depending on exactly what is required, but the typical cost for an E90 saloon is E395 plus VAT for tints, or £595 plus VAT for the combination of clear and tinted SupaGlass and a tinted rear screen.

An E65 7 Series would be E750 or E1095 by comparison, a Z3 with SupaGlass, £350. In fact, it's not just the size of the car that dictates the cost, but also the complexity – for example, the little Renault Clio is a particularly tricky task and has a price to match. The company has templates to fit almost any conceivable application from Bugattis and Bentleys to Land Rovers to Transit vans. It's a lot of money when you compare it to some of the mobile units out there but as we watch the process unfold, it's clear where that money goes –it's very labour intensive and quality is everything. Also, that includes a lifetime warranty and if a window is broken, Pentagon will replace the SupaGlass free of charge.

Pentagon's experts spend a long time discussing the job with the client to ensure the customer knows precisely what is available and selects the right product. In this case, our ad director Andy wanted a fairly subtle rear tint on his 3 Series saloon to keep the cabin cool and enhance the car's looks, with the added security of the SupaGlass laminate. Once the decision is made, the check-in process records the condition of the car and the details of the work to be carried out. The next stage of the process is to get the glass out of the car. As we mentioned, this car is getting the front windows coated with clear SupaGlass while the rear side windows get smoked SupaGlass and the rear window gets a simple smoked tint.

Pentagon has two specialist de-trimmers. They are experts at removing the various trim-panels and getting the windows out. It's typical of Pentagon's approach that they don't have multi-tasking staff doing various stages of the process. Each aspect is handled by an expert to ensure the highest quality Of workmanship.

With the glass neatly stacked on a trolley, the car is ready to be treated. There are two methods of application, wet or dry, and we witnessed both. The dry application uses a special, custom-made laminating machine, built to Pentagon's specification, which allows the SupaGlass to be applied perfectly, catering for the curve in the glass and applying the exact amount of pressure required. Before it goes into the machine the glass is cleaned thoroughly. The whole facility is kept as dirt free as possible and the windows are given special attention – any particles of dust, dirt or hair that get under the film can render the job unsatisfactory and force it to be re-done. Once out of the laminates, the film is trimmed to shape by hand (each knife blade is only used for one cut to ensure a perfect edge) and then carefully filed to give a nice smooth finish. The wet process involves a template being cut from the film on a cutting table and then fitted to the car with the windows remaining in situ (like the rear quarter-glasses and rear screen).

The window is sprayed with a special solution using water filtered by reverse osmosis. This allows the film to be moved around and positioned exactly on the window by the specialist fitters.

Watching the rear window tint going on shows just how tricky the job is. The template is shaped to the curvature of the glass by laying it on the outside (with its protective membranes still on) and using a heat-gun to allow it to hug the contours of the window. Then the interior is cleaned thoroughly and the solution is applied. Next the film has its membrane removed and is carefully lifted in and placed roughly in position. If any dirt or dust is picked up during this stage, the whole process must be started again.

With the film on the glass and correctly positioned, an assortment of specially designed and adapted spatulas is used to squeeze the moisture and air pockets out. This also activates the adhesive that allows the film to bond to the screen. For somebody who gets air bubbles in car stickers, watching the skill with which the job is done is very impressive.

Special strip lighting allows them to check for any imperfections and the car is allowed to dry out thoroughly before another quality inspection. Only if it is perfect is the car allowed to return to the customer. The company also recommends that the car is returned a few days later for a further check.

With the glass and trim refitted, the job is done. Andy seems delighted with the result. 'It looks great – subtle but noticeable, and the colour of the tint suits the silver paint. As well as the promise of improved comfort in the cabin I like the fact that people can't see in. Also, with a young son travelling in the back, the added safety benefits provide more peace of mind. And I have to say, the quality of finish is absolutely excellent.'

If you want to find out more about Pentagon's products and what the company can do for you, visit the website at pentagonglasstech.com or call 0800 279 2795. As well as the Acton HQ there are 12 UK franchises and 11 international licensees.

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