Carbon fibre frames are manufactured in vast, high-tech
facilities by technicians in white coats wearing rubber gloves,
right? As a rule, yes. There is another way, however; one
that is not so far removed from the traditional techniques beloved
of the traditional small-scale frame builders, artisans and craftsmen
for sure, who for much of its history built the frames that carried
the gods of professional cycling. It is the way of the mitred tube, the
frame builder's jig, and the bespoke fitment, and it is as relevant in
the era of carbon composites as it was in the age of metals.
For proof, one need look no further than the northern Italian
city of Padua, which boasts the second oldest university and largest
town square in Italy, Europe's first anatomy theatre, built in 1594,
and Galileo's desk. Padua is considered the economic centre of
the Veneto, the part of Italy that also contains such powerhouses
of the cycle industry as Treviso and Vicenza. On the outskirts of the
city, in an industrial estate in Ponte San Nicolo, may be found the
firm of Billato Linea Telai. If the name is unfamiliar, it is because until
recently the large numbers of frames that were built by the Billato
family business, which was founded by Silvio Billato in 1954, were
then sold under another name. It's a practice with a long tradition
in Italy, and one that is usually kept quiet for obvious reasons.
A little digging, however, produces a few nuggets: one famous
customer of Billato was the once-great firm of Legnano, which,
prior to the Second World War, sponsored a team with both Gino
Bartali and Fausto Coppi on its roster. The emphasis was always on the high end, lightweight sector of the market, and the firm built around 12,000 frames for the Belgian Concorde marque, including the frames for Sean Kelly's PDM squad. Billato also built the Greg Lemond bikes ridden by the Z and GAN teams as well as Lemond's own range of steel road bike frames. Once Silvio's sons, Roberto and Silvano, who joined the firm in 1979 and 1984 respectively, began to take over the reins, the firm started to con- centrate on small-scale, top-level production, and when the Look- sponsored Chris Boardman needed a steel-tubed frame for his athlete's hour record, the French composites specialist turned to Billato. Keen observers of the pro scene over the last decade will be able to add more names, but the point is clear enough. Few builders have a finer reputation within the industry itself. This anonymity was for many years entirely to the liking of Rob- erto and Silvano, not least because it guaranteed a steady supply of work. Local Italian racers and friends of the family might be able to acquire a frame carrying the name Billato, but otherwise they were not sold openly until some time in 2003, when volarebikes. com website owner Neil Hassan persuaded Roberto, who looks after sales and marketing, that there was a market for frames bear- ing the Billato name. Dipping a toe into the world of retail proved so successful that the firm had to move to its current premises just over a year ago.
Not that Billato has had to change proven working practices. The firm has a staff of just five, with Silvano the brains behind the technical side. Production is relatively low at around 1500 frames per year, each built by hand on the premises. Anyone familiar with traditional frame-building practices will recognise the various jigs, milling machines and welding apparatus stowed roughly around the workshop amongst racks of part-finished frames and piles of fresh tubes. These, of course, are the tools of the artisan frame builder's trade, even if TIG welding is something of a newcomer in historical terms. In fact, like brazing, long used to join steel tubes, TIG is used less and less at Billato, simply because aluminium frames, along with those in titanium and steel, make up a decreas- ing slice of production. In the case of aluminium, this is down to perhaps 10 percent of the total, with the others taking perhaps half that again. No need to ask what takes up the lion's share, since the boxes full of black carbon fibre tubes occupy far more space than those holding bright, shiny metal. Beyond a large oven at one end of the room and a deep chest freezer in one corner of a side room, there's little apparent concession to the supposed demands of composites manufacturing. Sure, there's a small 'clean' room, but several stages of a process that Roberto dubbed 'Carbon Wrap System' are carried out right in the middle of the workshop. This technique for building a carbon fibre frame has been in use for around a decade, and is proven in competition.
Gilberto Simoni's 2001 Giro bike was constructed in precisely this way. It is the culmination of 25 years' experience with carbon fibre tubes at Billato. The advantage of 'CWS' lies in the way it allows individual carbon fibre tubes to be joined at any desired angle in much the same way as more traditional materials. This is, of course, the key to true custom sizing, which is Billato's speciality. Should a cus- tomer require a fitment, the firm is equipped with the delightfully named VeloSapiens computerised measuring system. Before you can join tubes, first you must make them. Some car- bon fibre tubes are available off the peg, as are one-piece seat and chainstay mouldings from suppliers such as Deda. These latter are still an option on Billato frames, since the production technique can incorporate them perfectly easily. Round tubes of various diam- eters, bought in substantial lengths at some cost saving, are used for much of the Grancorsa model, which is the least expensive of the three Billato full-carbon frames. For the Competizione and marginally heavier Supercorsa, however, Billato uses tubes and even stay mouldings designed in-house. Roberto says it is so sim- ple as to be hardly worth mentioning. "We draw the shapes we want, a local machinist makes the moulds in two halves and we send them to a local specialist to do the moulding." It is a bit more complicated that that.
Carbon fibre, invariably in pre-preg form, comes from sources such as Excel Composites in France and ACG in the UK, and is laid up in the moulds strictly according to Billato's specifications. Silvano prefers HR, or High Resistance carbon, to the more modish High Modulus; it is stronger but less stiff, and makes a more resilient, forgiving frame. A carbon-Kevlar composite fabric, or 'CK', is also used to improve vibration absorption and toughness. A typical tube will employ an inside layer of twill, followed by several unidi- rectional layers laid at either 45 degrees each way to resist torsion or lengthways to resist bending. The final, outer layer will again be a woven twill, which protects against damage. Sounding a little like guesswork, the precise sequence, number and angle of layers is, in fact, the result of calculations carried out by Dottore Nicola Petrone of Padua University's engineering department. "Carbon is not so difficult to use if you know how to make the fibres work for you," says Roberto. "Our collaboration with the university means we use the right amount of fibre, and put it in the right place.' The moulds themselves are mostly machined from tough 7020 aluminium alloy, and can be expected to churn out around 3,000 pieces before they wear out. Steel moulds, costing around 4,000 euros compared to the 2,500 eurosof the aluminium version, last for around 10,000 pieces, and would appear more economical. However, Billato tends to change tube profiles after fewer than 3,000 pieces, making aluminium the better option. "We can have whatever profile we like," says Roberto. "Round section is best, but we can get the same results with a more aesthetic look. Besides, we can shape the ends of the tube for extra strength." Silvano mitres the tubes in the same way as for aluminium, leav- ing a cut edge that is an exact match for the surface of the tube it is to join. Prior to cutting, precise angles are calculated using a program called EasyFit04, written by Ingegnere Valentini, who in his spare time works for Beretta, the small arms manufacturer favoured by James Bond.
The various tubes and components such as dropouts are mounted on a jig to check for accuracy prior to bonding. Criti- cal to the strength of the finished frame, the aluminium bottom bracket shell receives special treatment. Following much experi- ment, Silvano found the best option was to weld a short tube to the shell. This tube is then bonded to the inside of the seat tube, making it immovable once the frame is complete. The top of the seat tube receives a composite sleeve, itself previously moulded around a 31.6mm mandrel to ensure a precise fit for the seatpost. This sleeve is cut away at its lower end, the front half remaining to reinforce the bottle cage boss area.
Once satisfied that everything fits, Silvano prepares the bonding
resin. Applied to the edges of the tubes, it leaves, once hardened,
a clean surface ready for the next stage. This is carried out on the
now one-piece frame next to the chest freezer, from which Franc-
esco withdraws a sheet of greenish plastic. On the back is a piece
of carbon fibre twill, kept at –18oC to prevent premature harden-
ing. Expertly cutting the whole to shape, Francesco wraps it around
the appropriate junction, pressing by hand to make it conform and
warming the plastic sheet to ease removal. The result is a kind of
customised 'lug', which can be as thick and extensive as the builder
desires. Only when every junction has been wrapped is the frame
placed inside a large plastic bag. This is taped up, a valve inserted
and the air sucked out, leaving the entire frame subjected to a sur-
face pressure of about 14psi, or one atmosphere. This ensures that,
while the frame is cooked overnight in the oven at 125oC, the fibres
are properly compacted and excess resin forced out of the join.
It's a labour-intensive and hence expensive process, but the result-
ing all-carbon frame can weigh as little as 900g. The rear dropouts
are CNC-machined 7020 aluminium with an integral gear hanger,
which Roberto says is so strong that there hasn't been a breakage
yet. Customers who prefer a replaceable hanger can opt for a Deda
Monobox rear end even on the Competizione frame. The Billato
range comprises three carbon fibre models, but traditional materials
are not forgotten. The Stradale combines scandium aluminium alloy
with carbon stays, while the Gran Premio is built using hydroformed
Deda 'Race' 7003 aluminium. Custom-built time trial, track and
cyclo-cross frames are available in either full-carbon or all-aluminium
construction. Steel and titanium frames complete the range. Billato's
recommended fork is Look's HSC 5 SL.
Completed frames are driven some 50km west to Duebi Verni- ciatura, a small paintshop with, if the frames hanging on the wall are any guide, some big customers. Driving back into Ponte San Nicolo, Roberto extols the Veneto. "We have everything for cycling: the Alps and Monte Grappa to the north, the plains around here, and, of course, the coast. For driving, the roads are very good." So too is business. The latest aspirant cycle manufacturer to make use of Billato's expertise is former Classics king Johan Museeuw, who has recently launched a carbon fibre frame rein- forced with flax. The claimed advantage of this natural fibre is that it has exceptional vibration-reducing properties. Roberto smiled at the prospect of the 100 per cent flax racing frame, as proposed in the Belgian champion's press release. After all, building a frame in flax is no more difficult than making it in carbon fibre and Kevlar. Just ask Silvano read more