Stats, Facts, & Random Thoughts - The Pilot
After reading Steve’s and Errol’s recent blog posts, I started thinking about the changes I have seen working within the collision industry and thought to share some facts, stats, and random info from courses I have attended. All of these plus the pressures of time - the one thing we cannot accumulate or carry forward, 86400 seconds pass daily, and once the clock strikes 12 the bank resets; onward to tomorrow and a chance to do better. Time, which we never seem to have enough each workday coupled with many changes in recent years are all factors that contribute to techs struggling with repairs on today's vehicles.
Did you Know?
Collision technicians can squeeze the trigger on their welder 20,000 times in a calendar year, which is pretty easy to see when presented with 2 different processes: aluminum pulse and silicon bronze brazing = struggles. Different techniques, different visual cues, even the sound is different, and the key - “repetition” do anything 20,000 times or more, it is muscle memory, not conscious thought.
Approximately 10 types of steel were used in the year 2000 car models. For 2020 models, there are close to 200 types of steel. Furthermore, 140 should only be joined with STRSW (squeeze type resistance spot welding) a low HAZ- heat affected zone. or alternately silicon bronze brazing (which is not traditional welding). Unlike welding, the base metals are not melted and puddled with filler material to create a new alloy, silicon bronze flows out and extends to the edge of the heated area and relies on the total surface area to create a robust flexible joint.
I watched automotive crash tests in a course on steel and joining techniques. What stood out was when seeing early model vehicles involved in collisions, it was like watching an accordion bellow closing; they hit one another and just got shorter as the metal folded. Watching cars of today crash is like a midway bumper car ride, each bouncing off another and careening in opposite directions.
Elastic steel is a term that I use to describe the passenger compartment all tied together like a roll cage of a race car, the material is designed to flex. The energy travels around the cage and returns back to the point of impact as well as dissipating throughout the rest of the vehicle. Carefully designed zones to slow the transfer of energy to the people within. Bumper cars, not accordions.
Within the last 7 years, there has been more emphasis on the type of filler wire to be used for your MAG (steel) welder. Steel wire for body panels is not rated for higher-strength steel. In fact, 550 mpa, the tensile strength of standard steel filler wire, begins to weaken the joint made as it has less structural strength than the materials being welded. Not to mention HAZ- heat-affected zone - if nothing else FORGED IN FIRE taught us something about overheating steel. Many of the steels, in particular, ones used for the passenger cabin protection - the integral safety cage for lack of a better description is particularly sensitive to HAZ (heat affected zone) the coloured ring around the joint area
In a seminar on early warning brake sensors and 3D measuring, 3mm is the usual tolerance for thrust lines- how the car travels down the road and the basis for 3D measuring being in the forefront for collision repairs. The presenter stated a 1mm deviation on a braking sensor could lead to a 2-meter change in the read zone.
Techs are good, in fact, many can get the repair point on a rail to within 1mm of the opposite side using a tram gauge. The challenge from the OEM. Can that be validated throughout the height plane front to back (the why of measuring the complete height plane) or read on?
Fixturing jigs on our benches are mechanical 3D measuring points - that is why we calibrate benches. The Cameleon Universal Jigs work the same as the dedicated jigs to locate a vehicle. Universal fixturing systems from other manufacturers rely on the measuring system to confirm correct alignment.
Do We Pull Dents or Do Panel Repair?
The techniques highlighted in Errol's blog “Miracle System Glue Kit” - refer to glue pull or low intrusion panel repair techniques. Paint on is much easier to track the body lines and see the damage, and good lighting is essential - a little side ramble, however, the point about panel repair is valid. Dent pulling (the term) is almost like kleenex (the universally accepted name for tissues), it's just too bad that it also encompasses some of the less finesse-oriented tools in use for collision repair. The techniques we are presenting today reflect a reduction in panel intrusion. With more inaccessible areas there is no opportunity to see whether the repair is causing additional damage.
Materials in cars today are chosen for weight, strength, recyclability, and cost to produce. Do not forget Aluminum (not new 1928 Essex was aluminum bodied) for swing and body panels. 95% recyclable, strong, and very light all of which assist in better fuel economy.
Speaking of fuel economy, the new CAFE standards will increase fuel efficiency by 8% annually for model years 2024-2025 and 10% annually for the year 2026 car models. They will also increase the estimated fleetwide average by nearly 10 miles per gallon for the year 2026 car models, relative to the year 2021 car models. 36mpg average today, 49 mpg for 2026. Reading some articles regarding how the manufacturers follow a complex (read $$$) formula to work towards these annual targets. Here is the link to a Ford powerpoint on the subject.