Properly notched tubes don’t just make for a better looking race car, they make for a stronger–and safer–one too
A great fabricator can make the process of building a race car seem like creating art. And there is a lot of art to taking a big pile of tubing and a stack of sheet metal, and maybe an old chassis too, and turning it into a car capable of winning races.
But there is a lot of science too. The best fabricators have an understanding of geometry, can accurately measure and cut and aren’t flummoxed by compound angles and curves. Having the right tools certainly helps, but more than anything it is important to know how to make the most of the tools you do have available to you.
Whether you are building a race car from scratch, or just making some repairs or updates to your trusty old ride, two of the most important skills for anyone doing fab work on a race car are to be able to apply a good, strong weld and be able to properly fit up roll cage tubing.
It can be tempting to go with the “good enough” method when fitting up tubing. In other words, don’t worry about getting two pieces of tubing to fit as closely as possible, simply throw a bunch of weld at the joint to fill in any gaps. But it doesn’t matter how good your welds may look, filling a gap with welding wire is never as strong as two pieces of tubing that touch each other all the way around with a single bead of weld that properly penetrates both pieces of steel.
“Notching” is the name of the process to shape the end of one piece of tubing so that it fits around a second. Practically every joint on a race car between two pieces of round tubing requires notching. There are several ways to properly notch a tube. Some are faster than others, and some make it easier to make precise notches, but all can produce quality notches that provide a tight fit between tubes if you use care.
To find out what options are actually available to racers and car builders, we called up Mittler Brothers Machine & Tool–the most widely trusted company in racing when it comes to fabrication equipment of all types–and they gave us a rundown of different notchers and how they work. What is cool is that, like we already mentioned, all of these options can be used to build a strong, safe roll cage.
The ultimate notcher is a horizontal milling machine type like you see here. It cuts very quickly and produces precise fit ups suitable for TIG welding (which requires minimal gaps between pieces of tubing). The tubing is clamped in a vee block jaw vise and fed into the rotating milling cutter to the desired depth.
Mittler Brothers Machine & Tool / 800.467.2464 / mittlerbros.com