Choose the language.
TKART magazine How To | Cutting, bending and welding: the right recipe for producing a chassis
Exclusive Content

CUTTING, BENDING AND WELDING: THE RIGHT RECIPE FOR PRODUCING A CHASSIS

Max Bernardi
06 October 2018
alt
alt alt
Advertisement
INTRODUCTION
It is not false to say that a kart chassis is “only a few tubes welded together”. Few, however, know or even just imagine the studies and testing necessary to define the design the geometries, choose the materials, establish the processing order…to achieve a product which ensures the very best performance on the track.
Research and development never stop and, although the designs of the most used frames have been quite similar for several years, this does not change the fact that the newer technologies have had a significant impact in the production process of a chassis, allowing a greater quality control in production as well as improving the adaptation ability of the chassis to the changes made on the track.
The realization of the chassis, therefore, remains a process which is as delicate as decisive, and the leading companies in the field rarely share their information. IP Karting makes an exception and opens the doors of its company to allow us to closely discover all the phases of the production of a frame.
alt
1 DESIGN
In the past, everything started from an idea, an intuition which led someone to sketch a drawing on a sheet of paper and, from there, start to create a chassis, maybe even with some unconventional curvatures. Nowadays, more than the design of the frame, the fundamental parameter on which one works is the material by studying the different characteristics and verifying its mechanical elasticity.
Clearly, however, the design stage of the frame has not disappeared, although the PC has replaced the pencil and we rely more on the data collected by the tests and the races on the main international tracks than on the manufacturer’s intuition, which however still remains an important part of the design process.
IPK, with the brands Formula K, Praga Karts, OK1 and recently RS collects a lot of useful information in this sense, focusing in particular on the different response of the materials according to the type of tires which are used in the various championships. On the basis of all this, it is decided which material is most appropriate and the other characteristics like the tubes’ diameter, the wheelbase and all the dimensions which serve to develop the first prototypes to be tested on the track, are defined.
Then, it follows a path made of verifications, rapid changes of the welding jig and the cutting measurements, production of new prototypes, tests…and so on, until the final rendering of the chassis is achieved.
At this stage, we move to the approval phase which will allow us to use the new frame in the races called CIK-FIA.
Only after obtaining the approval of the Federation, the series production begins, whose primary objective is to create batches of productions equal to each other, maintaining an unchanged quality of each and every chassis destined to the final end users.
alt
The technical office defines the chassis design evaluating the information collected by the racing team during tests and track races
alt
The technical office defines the chassis design evaluating the information collected by the racing team during tests and track races
alt
Before the homologation, a new chassis must be tested on the track in every condition, in order to verify the project and improve upon it if necessary
2 THE TUBE
As we have seen, the choice of the tube to be used  is, perhaps, the most decisive stage for all the successful outcomes of a chassis destined to be used for racing. Codes such as “25CrMo4” are not randomly placed on the chassis: they indicate the name of the steel used to build the frame.The diameter, therefore, a parameter which is always rightly considered first when it comes to tubes for the kart, is not the only characteristic which vary the bending and the ability to adapt to the adjustments that are made on the chassis. It is not by chance that, according to the chassis to be manufactured (rental, mini, single-speed or shifter), different materials are used. All, of course, carefully selected in the awareness that, when the production of large quantities of chassis starts, it is of essential importance to be able to count on the right materials to maintain the appropiate standards from the first unit to the last.
alt
IPK tubes’ warehouse. Here the operator finds the rods divided by diameter and types of materials
3 CUT
Starting to analyze the actual production phase, the first process necessary to produce a frame for a racing kart is that of cutting the tube. The precise measurement to be cut is communicated to the automated bending machine, which also takes into account the elongation of the material that will take place in the bending phase which is different depending on the type of tube used. In addition to ensuring perfect uniformity amongst the various lots of production, this precision allows IPK to optimize the amount of material needed.
alt
The machines dedicated to the cutting phase
alt
The machines dedicated to the cutting phase
Continue reading the article
This week only, 20% off!
2
Explore these and many other
premium contents
Go to Magazine