Side Window Security
It's a problem that's been around from the earliest days of automobile use. How do you secure the contents of the vehicle when the sides and roof are made out of fabric. A simple pen knife can easily defeat them, and allow access to whatever's inside. We had that same problem with our Defender.
As a rag top vehicle, and one that was going to have gear inside it almost all of the time, we were worried about theft and damage. A new top like the one we bought from Badger Coachworks cost US$2,400.00. So the last thing we wanted to do was to replace it after someone had used a knife to gain access and rip off all our stuff.
Early days webbing nets to stop cargo from falling out.
Initially, when we had the truck boxes inside the cargo area, we didn't worry so much about gear theft. But what we did worry about back then was losing gear that might fall out the side window if we were on trails with the side windows zipped off. You see, we could sometimes pile up stuff inside the cargo area so it was resting on top of the truck boxes. This meant that any driving around curves, or tipping sideways on a rough trail, could see gear falling out the sides. So to combat this, we bought some black 1" webbing material and actually sewed up a net that attached to the securing rail we put on the side of the body, and the upper support for the roll cage. That net worked well for its intended purpose, but did nothing for security.
Once we had built the roof rack, there was no way anyone could gain easy access to the cargo area through the soft roof, or from the back because of the swing gate. But there was still the side windows. That's when I had the idea of replacing the side nets made from webbing, with ones of a similar look made of thick aluminum sheet. The process for this is explained below.
You can look at the photos below individually with the descriptions, or open a "picture only" slideshow here.
We chose 3/16" aluminum sheet for this project so the grills will have a substantial feel.
Once the blanks were cut to size and shape, the grid was laid out. The two plates were then bolted together and a single hole was drilled in each square to be cut out, so the router bit could be inserted.
In order to get all the cutouts identical, a routing template was made. We then clamped a straight edge to the blanks for the template to slide along from one cutout to the next. That way they will be in perfect alignment.
The template works with a collar that is part of the router baseplate. So as long as the edges of the template are perfect, then the routed rectangle will be as well.
The template cutout has to be larger than the finished rectangle to allow for the difference in diameter of the collar compared to the router bit size.
Both grills were bolted together and routed at the same time. This ensured that both grills would be identical, and reduced the production time.
The double thickness was also required for the next step, which was chamfering all the edges. This was done with a router bit that has a ball bearing guide.
The chamfering process is easier than the initial rectangle routing because so much less material is being removed.
Here the chamfered cutout can be seen alongside the unchamfered one. We needed the double thickness because without it the ball bearing end on the router bit would protrude below a single plate and have nothing to guide along.
The chamfer is subtle, but it does the job of creating a professional looking part.
It also helps in the powder coating process. When the powder is heated in the oven for fusion, the molten coating tends to pull back from sharp edges leaving almost no material covering the edge.
Special attachment brackets had to be made because the grill will sit at an angle to the lower rail that it screws to.
The small bracket has deliberate, angled faces. This was done by running the aluminum flat bar through an angled table saw blade. This was done twice, one for each face. Then the flat bar was cross cut to create the 1" wide bracket.
Four brackets were needed for each grill.
Although the bottom of the grill was going to bolt to the lower rail, the other three sides had to attach to the roll bar. To prevent damage to the rubber padding on the roll bar, we bent up thin aluminum hoops that would wrap around the bar and then bolt to the grills.
Since the roll bar padding had an unusual cross sectional shape, we made a wood template to bend the strap around.
The bending jigs were simply screwed to the workbench to hold them while the material was wrapped around them.
Along with the two main grills, we also had to make two smaller ones to fill the area between the main roll bar and its gusset bar. If we didn't, a villain could cut the canvas there and reach in and unlock the front doors.
The lower rail had to be drilled in place, and then countersunk for the stainless steel machine screws. The powder coating was drilled off, but the screw heads and countersunk holes were touched up with black paint to make them "disappear".
We even allowed for the roll bar fabric padding by machining the aluminum to fit.
In addition to the triangle grill, we also had to block out the 4" vertical slot between the roll bar and the door jamb. Otherwise a simple cut in the fabric would allow access to the inside door lock.
The finished assembly held in place with the thin aluminum straps we bent up.
Whether the canvas top is on or off, the look of the finished grills is very pleasing.
Top on, but windows removed.