Nerf Bar & Step Build
Several years into the use of the Defender, a problem started to crop up more and more. Oh, there was nothing wrong with the vehicle, but there was something wrong with my own aging carcass. I started to have problems with my left shoulder, and oddly enough, and the root cause turned out to be the Defender.
Spending up to four months a year in the sunny southwest, we used the Defender not just for off-roading, but also as our primary daily driver. So there was a lot of getting in and out of the vehicle. It was the getting in part that was causing injury to my shoulder.
Between the larger tires, and the three inch lift to the vehicle suspension, the entry point for the vehicle was about five inches higher off the ground. To get up into the drivers seat I had to grab the outside roll bar and pull myself up into the seat. So the old shoulder was suffering from a repetitive stress injury. The only way to solve the problem, since I can't trade in my old, worn out body for a younger model, was to add a step outside the door so the lifting could be done by my legs rather than my arm.
Since the vehicle was used a lot off road, and routinely required the full height under the door sill to clear obstacles on the trail, having a drop down step would end up being a problem. I had to devise a way to have the step, but maintain the off road clearance.
Early, during the vehicle modifications, I installed a set of rock sliders that I bought from Equipe 4x4. It was an Italian manufacturer of accessories made mostly for the Land Rover Defender. Since it made no sense to remove these and replace them with something else that accommodated a step, I simply designed some nerf bars that would support the step, and could be welded to the existing rock sliders. Here's how I did it.
You can look at the photos below individually with the descriptions, or open a "picture only" slideshow here.
Nerf Bar and Step Build Sequence
The first step (pardon the pun) was to bend the 1-1/2" steel tubing for the nerf rail and steps.
Before getting started, though, I had to decide whether to get a fabrication shop with a tube bending machine to do the work, which was expensive, or buy a small hand operated machine and do it myself.
I elected for the later, since the cost for the machine was about the same as the shop charges and work. Besides, I am no stranger to tube bending. We did a lot of this at our manufacturing business over the years.
To attach the nerf bars to the existing rock sliders, I needed to make standoffs. These standoffs would also do double duty, as they would provide the holes into which the removable step would fit.
The round tube in the middle of the piece is called a crush tube. When tightening down on the step securing bolts, this crush tube prevents the hollow rectangular piece from being deformed by the bolting force.
The rectangular standoffs were attached to the nerf rail using a small MIG welder which I borrowed from an old friend.
Dressing down the welds using a small hand grinder.
The finished nerf rail ready to be fitted to the rock slider on the Defender. Flawless "invisible" welds weren't necessary since they would all be covered by an anti-slip sheet material.
This is the actual step hoop. It turned out to be much too long, so to reduce weight I cut some material out of the middle and made it shorter by welding the two pieces back together.
Welding the straight, square tubing to the bent step hoops.
The end of the hoop tube was closed off to prevent water and mud from collecting inside the tubing and causing rust from the inside out.
The two components ready for the next fitting.
Since the step was a drop down style underneath the nerf rail, risers had to be added. To make the finished part as attractive as possible, I shaped the end of the riser to form fit around the step hoop. This was done "old school" using a hand grinder to do the rough cut, and then finished with a half round hand file.
In a production shop environment this would be done with dedicated shear tooling that would complete the finished shape with one step on a machine pedal. But alas, I didn't have one of these anymore either.
Ready for TIG welding.
The two completed sub-assemblies test fitted to the existing rock slider. You will notice here that the step has already been cut shorter in length.
Looking from underneath, you can see how the drop step inserts into the rectangular tubing. A bolt from above pulls the vertical tube with the collar up tight to the underside. This is why the crush tube was needed inside the rectangular piece. If it wasn't there, the force of the bolt pulling on the collar would "squish" (technical word) the rectangular tube.
The welded and assembled components.
Since the nerf bars will protrude about 5" from the side of the rock sliders, there is the potential for them to be bent upwards if they impact something on the trail. To add three dimensional strength, a vertical riser was added that would clamp to the vehicle roll bar and prevent this vertical deformation.
Because we wanted the ability to add other things to this assembly later on down the road, I made it so the vertical riser tube was removable.
The small tube that is inserted through the nerf bar and welded in place was another crush tube for bolting the vertical riser to.
A solid steel slug was machined with an internal thread so it could be bolted down onto the nerf crush tube.
The vertical bracing tube was coped on the end to fit around the nerf bar, and was drilled for "plug welding".
The vertical tube and the bolted on slug would become one piece.
The holes on the side of the vertical tube were filled with the MIG welder so the tube would be permanently attached to the bolting slug.
The top of the vertical riser had a flat plate attached to it that would bolt to one of the Protection and Performance aluminum clamping blocks.
Once it was all dressed down, aluminum checker plate covers were shaped for the step and the nerf bar, and the entire works went out for powder coating.
The Protection and Performance blocks, along with stainless steel fasteners make for a visually appealing assembly.
The checker plate covers were shaped, then powder coated for adhesion, and finally Rhino lined for slip avoidance.
In order to achieve a professional looking finish, the crush tube for the vertical brace was countersunk to receive a stainless steel 3/8-16 flat head machine screw.
The step and nerf bar covers were attached with 8-32 countersunk self-tapping stainless machine screws. This way if the covers got damaged, or the coating wore off, the covers could easily be removed for repair or re-coating.
Quick removal of the drop step could easily be accomplished by simply removing the two 3/8" countersunk bolts that can be seen here on the top of the nerf bar cover.
The completed nerf bar and step project. It blends in nicely with all the other additions on the truck.
And yes, all this work did resolve the problem with my aging shoulder.