Mandrel Bending

Conventional exhaust bending can cause a range of problems for your vehicle, including when the tubes collapse or crimp in the process. Poor exhaust bending can also reduce your engine’s power and economy. If you have a 4WD or commercial vehicle exhaust system, you will need several bends. The larger your tubing is the more severe the crimping can be if you use a regular tube bender, but with mandrel bending the size and diameter of your pipe will be increased.



Did you know…?
Beaudesert Exhaust is Australia’s largest stockist of mandrel bends.
We can bend 1 ¼ inch to 5 inch tube.
Enquire today and get a quote from the leaders in custom bending, use the ‘Get a Quote’ form.



Mandrel Bending Expertise

Beaudesert Exhaust’s C.N.C mandrel-bending machines are the solution to your custom exhaust problems thanks to the ability to bend pipes without restriction – no crimping or collapsing means increased airflow for your engine.

The specialised machines use a pair of half-round steel dies to hydraulically bend the outside of tubing, while an articulated steel ‘stiffener’ (the mandrel) works inside the tube to keep it from collapsing.

Consider how long it would take to make one piece of tubing with three bends in it, if you had to cut it in three places, cut out each bend from pre-bent tubing, and then weld each bend in place by hand. That’s nine cuts and six 360-degree welds. Our C.N.C. Benders achieve that in 30 seconds at the touch of a button.

Mandrel-bending machines are an expensive investment, so not all systems are bent using them. However, Beaudesert Exhaust is proud home to 8 mandrel-bending machines that have the capability to bend up to 5-inch pipe. So whatever your vehicle’s power requirements are, we can accommodate them! We also bend a variety of custom jobs including but not limited to headboards, hand rails, roll bars and pipe work.

Benefits of Mandrel Bent Systems

To see how much of an improvement mandrel bending can make, take a look at the below chart. It shows the effective cross-sectional areas for press bent and mandrel bent pipes. In the press bent column, two numbers are shown, corresponding to a 20% and 30% reduction. 20% is typical for a slight bend, 30% for a larger bend. As can be seen from the table, a 2.5 inch press bent downpipe is actually smaller in cross-sectional area at the bend than a 2.25 inch mandrel bent downpipe!

Nominal Pipe

Press Bent Area
(Square Inches)

Mandrel Bent Area
(Square Inches)


2.74 / 3.13



3.43 / 3.92



4.94 / 5.65



Figure A

As seen in figure A, the 3-inch pipe that is mandrel bent measures 3 inches at the centre of the bend. True 3-inches throughout the pipe will give you 35% less backpressure. Less backpressure results in increased horsepower, torque and improved fuel economy.

Figure B

As seen in figure B, the 3-inch stock bent pipe measures 2.5 inches at the centre of the bend. A 3-inch pipe with 2.5-inch restrictions will not be a benefit. An exhaust system is only as good as its weakest link, so why settle for restrictive sub par bending?