AUTOSPORT HISTORICS 25 JULY 2019 29KW HERITAGE
data allowed us to use the scanned part for reference,
enhancing structural elements as required to recreate
the component in its intended form.”
A 3D printed prototype was then made, using KWH’s
own equipment, in a thermoplastic called PC ABS. It was
fitted to the Alfa to make sure all was well.
“We made a 3D print of the cover, and fitted it to the engine
and chassis to make sure it didn’t clash with the chassis or any
nearby components,” explains Smith. “Once we were satisfied,
we could be confident to go ahead and cast some items and
machine them. 3D printing allows us to be fast and accurate,
and to avoid expensive mistakes.”
No changes were required in this instance and so a new
aluminium cover (not magnesium for reasons of corrosion
resistance) was made and fitted to the Alfa. Not only was the
part delivered quickly and at a reasonable cost, but the CAD
file means future replacements will be easier to produce.
“Touring the KW facility was a real eye-opener for me,”
adds Stretton. “It showed what could be done with skilled
engineers using 3D printing. Components, body panels and
complete structures can now be scanned, digitised, designed
for manufacture and made within days using this approach.
Previously, much of this would not have been possible.
And if it was, it could have taken months.”
Smith is also keen to point out that such an approach
Original Alfa
cover was in a
bad way, but
scanning and
then CAD
saved the daydoesn’t have to be at the expense of established methods:
“Traditional techniques were used in making the cars and
sometimes you have to go and demonstrate the new technology
to show it can go hand-in-hand with those. Patternmakers
and foundries are beginning to understand the benefits of
scanning, CAD and 3D printing.
“We planned this business as a modern service – not to
replace the traditional craftsmen but to complement them,
either for authentic parts or to improve them, as required.”
That final line – “to improve them, as required” – could be
seen as a concern. KWH lists four levels of work in this area,
ranging from like-for-like restorations at level one to complete
redesigns (for example, installing an EV powertrain or exchanging
leaf springs for coil springs) on level four, via ‘invisible’ and
‘visible’ enhancements. While perfectly reasonable for road cars,
any kind of enhancement has the potential to cause issues in
historic motorsport. If new parts are enhanced they could provide
performance advantages over the originals, and therefore over
those preparers and owners running authentic parts.
Smith points out that this can be used for good reasons by, for
example, improving the reliability or durability of a component.
“There’s little point in remanufacturing something you know will
fail, or has traditionally been frail,” he says. “That’s particularly
important where historic cars are going faster or being used more
than they did in the past, and can be done by switching to a