

Updated 5/23/2006
Graftek made a huge impact on USA
racing. Premiering in 1975, these bicycles were the precursor to all the glued
together carbon fiber cycles such as Trek, Look, etc. that have became so common.
"I
used to work for Graftek from 1976 to 1979 in the R&D group, including
some work on the bikes.
Our facility was located in South Plainfield, NJ, and that
was where the bikes were first built until the facility was closed down
in 1978. Towards the end of production in NJ, I was the painter of
choice for those. I had good experience painting cars as a hobby,
and they were not having good luck with the finish coming out of the
electrostatic paint room, which was also used for the fishing rods and
golf clubs.
We were using DuPont Imron
clear coat
on the tennis rackets, so they asked me
to try a few bikes and see how they came out. The polyurethane
turned out to have a great "wet" look, but that ended up getting me into
the painting business once a week rather then R&D work.
The Graftek carbon fiber tubes were actually an aluminum-carbon
fiber hybrid. The epoxy impregnated pre-preg was cut and rolled
onto the tubes in the proper fiber orientation to the individual tubes
best intent. Because the aluminum tube could carry the "torque",
the fibers could be at a 10 to 15° angle to provide maximum stiffness.
This Al-CF sandwich was wrapped with Tedlar tape under tension to
compress the composite, then the tubes were put into an oven for curing.
The tubes were then unwrapped after full cure, and run through a wet
sanding station to provide a smooth surface.
The lugs and dropouts were made on site, brazed together.
They were then send out to a plater for polishing. Upon returning, the inside of
the lugs / dropouts were bead blasted. Both the ends of the
corresponding tubes, the lugs and dropouts were coated with epoxy, then
assembled in a holding fixture. The entire fixture would then go
back into the oven for curing. A little cleanup followed, and they
were ready for paint and decals.
I can't remember if they were making forks at the facility at that
time, but one of the projects we were working on was carbon fiber
covered forks. They were not true C-F as in terms of the tubes,
but were covered to look like they were. I do not believe any of
those make it into production.*
The South Plainfield site closed at the end of
1978 due to union issues there in NJ. Sporting goods got broken up
between CA and FL.
Jack Schmidt "
* Editor's note: These frames were actually shipped (at some point
late in the production) with chromed forks of Columbus steel tubing,
Haden cast crowns, that were wrapped in the top section with a thin
carbon fiber fabric layer. At the time, those of us who sold these,
considered the carbon wrap to be mostly cosmetic, carrying the "carbon
theme" forward for marketing purposes. |

Investment cast
stainless steel lugs. A first?
Pic from Bicycling magazine May 1976
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The frames were made of
carbon fiber "prepeg" tubes which were
then glued ("bonded") into the highly polished lugs and dropouts.

The above 1977 photo* shows John Howard
at speed on the
Graftek. These were the first widely available carbon fiber bikes; a brave
but
ill fated attempt at mating new materials. Sadly, these frames suffered from
what proved to be the Achilles heel of all bonded bikes, that of the joints pulling apart.
(*Illustrations
from the original sales brochure)
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