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Inside Gore: Bring on the Rain

Peter Stuart
4 Apr 2017

Gore’s cycling division is a tiny cog in a giant industrial machine, but has played a big part in the development of cycling gear

One October day in 1969, late in the evening, Bob Gore took out his professional frustration on an unsuspecting length of polytetrafluoroethylene (or PTFE as it’s better known).

Having spent fruitless months trying to stretch the material without it snapping, as the story goes, Gore gave a heated rod of PTFE an angry, forceful tug.

To his amazement it stretched tenfold in length, and in those few seconds he had changed its already miraculous qualities dramatically.

It was the birth of a new material called ePTFE (‘e’ meaning ‘expanded’), which became Gore-Tex, and which has been keeping cyclists dry for decades.

I’m standing in a 10m tall glass chamber, and several tonnes of water are about to come crashing down onto me to reinforce how effective that 50-year-old experiment is today.

It’s all in the interest of science. Alex Metcalfe and Jurgen Kurapkat, heads of sales and communications at Gore, are putting me on the front line of its waterproof testing process. 

‘All of our prototypes have to prove their performance for the intended use in the rain room using a variety of tests,’ says Kurapkat.

‘That’s why we have these nozzles all around, to test the products from all angles in a cycling position.’

Mind the gap

Kurapkat advises me to do up the zip fully, pull the hood tightly over my head and avoid any gaps between trouser and jumper.

‘Otherwise the rest of the day will be a little bit uncomfortable for you,’ he says with a smile. Beneath the thin Gore-Tex fabric I’m wearing the only set of clothes I’ve brought for this trip, and it will be a long way home in a soggy cotton jumper if the test goes badly.

Having only met Kurapkat and Metcalfe 10 minutes ago, I start to wonder at my judgement of their characters, and consider whether soaking a visiting journalist might be a regular bit of fun for them.

Above me, what begins with a trickle of water leads to a torrent and I feel myself beaten with a dense rain.

Gore has emulated perfectly that rare sort of rain that simply soaks through most clothing. My face feels like a waterslide.

When the ordeal stops I shake myself free of the bulbous droplets that sit on the surface of  my jacket and tentatively remove the Gore-Tex garments.

To the delight of the team there’s not even a single drop of water on my clothes. 

‘Each rain chamber is different all over the world,’ Kurapkat tells me. ‘But we have standardised equipment and processes so everything experiences this same test.’

Walking through Gore’s vast complex in Feldkirchen-Westerham, south of Munich, gives a glimpse of the company’s scale.

‘We are nothing,’ says head of design Clemens Deilmann, referring to the cycling division. ‘We are not even 1% of the company. Huge industries are supplied with our stuff – we are marginal.’ 

The facility here is geared towards cycling and running wear, which comes together under the umbrella of the Gore Fit Team.

It’s a massive building but represents only a fragment of WL Gore & Associates, its 10,000 employees and £2.4 billion in annual revenue.

But Gore’s presence in the cycling market has changed things more than one might think.

Science of soaking

Chemistry isn’t always in the forefront of our minds when it comes to buying cycling gear, but ePTFE, Gore-Tex material, made waves that are still rippling though the cycling market.

Of the many diverse uses for ePTFE (see p103), Gore-Tex’s outdoor and sports clothing is possibly the most iconic, thanks to its ability to repel water while still being permeable to air.

The ‘breathability’ of the fabric comes down to a series of pores that are 1/20,000th of an inch in diameter – too small for water molecules to penetrate but large enough to release air, water vapour and sweat from within.

It quickly found favour with walkers and mountaineers – and then came the Giro.

The Giro jacket was the Big Bang for Gore Bike Wear. It was created in 1985 out of the frustration of one Gore employee named Heinrich Flick.

He and a team of Gore employees were active cyclists and eager to see Gore-Tex technology put to use in the cycling market. 

While we sit in a reception room, as if by magic Flick pops up on the massive screen as part of a lengthy company infomercial.

He begins to tell his tale: ‘We wanted to sell the fabric to cycling brands but they didn’t want to buy it from us as they didn’t see the advantage that we portrayed,’ says the on-screen Flick.

With no cycling brands eager to push the costs of their clothing up four-fold, Gore decided to seize the reins and produce its own jacket. 

When it came out in 1985, the Giro Jacket cost DM200 – about £160 in today’s prices – and was thought too expensive for any retailer to consider.

Having dropped a few samples with a couple of retailers, it was less than 10 days before Gore received orders, and within three months it had sold 500 jackets.

It was a standout success, and generated enough excitement for Gore to launch a cycling division. 

Watching the film, it’s intriguing to see clothing that looks two decades ahead of its time being worn by kitsch 1980s cycling stars.

The aesthetic wasn’t helped by a crotch strap that ran between the tail and front of the jacket – quickly phased out following crashes from snagging on the saddle – but it kick-started a revolution in waterproof fabric in cycling. 

The premium waterproof jacket, now revived as the Gore One, remains its flagship, but even with Gore’s space-age material (quite literally – it has been used in NASA space suits) being waterproof, it still requires a lengthy process of design and validation.

‘With every garment that’s made out of Gore-Tex and claims to be waterproof, we have to prove that it’s waterproof,’ says Metcalfe. ‘That’s why we have the Rain Tower.

‘We keep one of these sealed garments, then the rest goes into production, and when people have a complaint we can investigate the difference between what we have as a sealed garment and what was produced.’

More than a slogan

Cheaper brands boasting ‘waterproof’ performance is a bugbear for Gore. ‘It’s significant that a garment is allowed to carry the black diamond of Gore-Tex. Waterproof is more than just a marketing slogan.’

Of course, Gore-Tex now is not the same as of old – it’s undergone a great deal of modification and fine-tuning.

‘Gore-Tex is still our trademark and still our patent, but we’ve continued to develop it as we’ve gone forward. It’s not like we’re stuck 40 years ago,’ says Metcalfe.

Yet while Gore-Tex is the real star of the show for Gore, it’s the lesser-known Windstopper fabric that has really infiltrated the cycling industry.

Castelli’s Gabba jersey is one of the success stories that uses Gore’s Windstopper. The Gabba utilises a Windstopper membrane and a water-repellant DWR spray treatment on the face fabric.

Any Gore-Tex clothing is actually a combination of three fabrics, all provided by Gore. First is the backer, which sits next to the skin, then the membrane – the Gore-Tex material itself – and a face fabric. 

The backer is necessary as while Gore-Tex is biocompatible (it’s not harmful to living tissue) it can feel rough and uncomfortable directly on the skin, while the face fabric offers extra insulation, durability and the ability to sublimate the fabric with a colour or pattern, which can’t be done with pure Gore-Tex.

‘We provide the complete material. It’s down to the brands to design the cut, zipper and any additional fabrics,’ Metcalfe says.

Despite the buzz around new all-weather clothing from other brands, Metcalfe points out that this is all old news to Gore.

‘We launched our first Windstopper jersey in 1997. We launched our first waterproof short-sleeve jacket, the Xenon, in 2008. So we’ve pioneered Windstopper or Gore-Tex jerseys for many years.’

The Gorey detail

Like many clothing brands, most of Gore’s cycling kit comes from factories in eastern Europe and the Far East. Producing with Gore-Tex is no trivial matter, though. Factories have to gain accreditation to use the material. 

‘The facilities are third parties who have to qualify for our standards and then they get a licence for Gore-Tex and Windstopper,’ Deilmann tells me.

The material is tracked carefully in certain countries to ensure no extra stock is kept for unauthorised military or aerospace use.

While production takes place all over the world, it’s here in Bavaria where Gore’s cycling products are designed and all Gore cycling fabrics are tested to a degree that few of us would conceive of when choosing one jersey over another.

The Rain Tower that drenched me earlier, and the neighbouring Storm Cube that emulates high winds, use advanced mannequins to detect where wind and water might get through. 

Testing is taken very seriously, partly on account of the prestige of the wider company. ‘If we have an aerospace contractor or surgeon using our jersey or jacket and they’re not happy with the brand, another division of Gore might lose out on a huge contract,’ Deilmann says.

There is a meticulous, clinical approach to testing the finished garments as well as the fabric itself.

‘You can put huge pressure on that,’ Deilmann says as he stands in front of a set of fabric tubes beating up and down to an almost comical rhythm.

He points to a machine beside it pumping huge pressures of water onto a patch of clothing. ‘This is made to test the seams – telling us if the seam sealing machine is working right, and the temperature being used is right, rather than a focus on the material itself.’

This pump will generate a waterproof rating for a garment, measured in metres.

‘The official definition of being waterproof is actually to a depth of just 1.3m, which is really low,’ Deilmann says.

This waterproof rating is based on the measurement of pressure created by a height in metres of water in a 10cm diameter cylinder.

Gore-Tex has an 18m rating, meaning you could fill a 10cm diameter, 18m high tube of Gore-Tex fabric with water without the fabric leaking, so while many items may claim to be waterproof, it’s only a relative measure of water resistance.

‘Even if it’s Gore-Tex but not taped then you know it’s not going to do the job,’ Deilmann says. Taping – covering the sewn seams with Gore-Tex tape – is a big part of Gore’s technical repertoire, and has evolved quite a bit since the original Giro jacket with its heavy 2cm wide tape.

To perfect that taping process, Gore does as much simulation of the production process as is possible here in Germany.

Guided by hand

The atelier, a sewing room in Bavaria, works as both a model production facility and a prototype lab. Sewing and taping is the most technical process, performed by a sewing machine heated to 400°C but guided by hand.

As a designer, Deilmann’s most ambitious plans often come awry when it comes to the practicalities of production. 

‘Working out the necessary pressure, the heat, the tapes and the way of handling the material is all part of what happens here. That feedback is key to letting our partners know if a design works in production,’ he says.

I can’t help but wonder, with the engineering power of a multi-billion-dollar industry behind it and dozens of patents, why Gore doesn’t pull up the drawbridge and keep the waterproof world of cycling for itself. 

‘Stimulation of the market is the main goal for us,’ Deilmann says. ‘For instance, we do Windstopper garments and people become aware of it, then Castelli or Specialized decide to use that material for something that will be used in professional racing.

‘For Gore that’s the best thing that can happen.’

It’s funny to think that a man tugging at a polymer 50 years ago, and an employee keen on cycling 20 years later, have made such a difference to the technology that allows us to cycle in comfort.

Leaving the sparkly white corridors of Gore’s German complex, I wander out into the Bavarian countryside – and into an onslaught of torrential rain.

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