Getting in and out of the canopy used to mean climbing up and down a ladder style step system. It was OK if you had two free hands, but if you were carrying anything, it became 'interesting'. So the next task was to design and build some steps.
It started out with some scratchy drawings of heights and angles. I needed to get to a height of 1200mm (about 4') above the ground to the 'landing pad', and I needed the steps to pack away into a 1700mm long space in the garage. They also had to fold up flat to make them fit, so I spent quite a bit of time playing with the angles and pivoting points.
This progressed on to designing the steps in a CAD program. There must have been a lot of dust on my computer monitor that the flash shows up - it certainly didn't look that bad when I was designing things! The critical points were the 2 pivot holes. They had to be far enough apart when opened to make the steps level, and also pivot 180 degrees to end up flat against the railings when stored. The perforations in the middle of the step were just to make them a bit lighter and stop them being slippery.
My first prototype used 2mm aluminium, but it turned out not to be thick enough as even gentle walking on it made the step flex a lot.
The next step was cutting them out on my little PlasmaCam plasma cutter. It was the first time I'd cut anything 3mm thick, and that took a bit of experimenting with the travel speed and pierce height to get a nice clean cut.
This is how they came out of the cutter. Each step was very light, even in 3mm.
With the second prototype being 50% thicker than the first, my hi-tech magnetic bender which I used for the 2mm prototype wouldn't even look at bending these. So it was back to the old fashioned mechanical brake to bend it all up.
The steps are designed to fold up, so I used some 19mm drawn aluminium rod as the hinging. That plasma cutter is incredibly accurate. The 19mm holes I cut were a perfect light friction fit for the 19mm rods.
Next up was making the rails to attach the pivots to. The idea is that the top rail pivots down and swings the steps out for use, and then rotate the other way to swing the steps back in again for storage. The pivot pins are welded to the outside of the rails and makes it quite rigid side to side.
Fixing the top of the stairs to the slide out landing took a few prototypes. The main problem was that the landing had to still slide into the truck body, so nothing could be protruding. In the end I kept it simple and just used 2 holes drilled into the landing, 2 locating pins on the rail ends, and some 8mm elastic rope to hold it in place.
This is the end product. Much easier to get up and down than the ladder, although the ladder is obviously always on hand for a quick stop when it's not worth setting up the stairs.
The white tape on the leading edge is non-slip and will make things easier to see in the dark. The side rails are 38mm x 25mm x 1.6mm structural aluminium (normally used to build fences etc).
Overall: quick to set up, very stable, quick to store away, and nice and light for easy handling too.
It's easier to see how they work with a video:
Sorry about the music! I felt compelled to add music to it but maybe Leo Kottke wasn't such a good choice!
Since I took that video I've fitted a stainless steel handrail at the same angle as the steps to give you something to hold onto, mainly on the way down.
When folded, the stairs pack into the garage with about 2mm each side to spare.
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