The church was sponsoring a lecture with the topic “Finding trust in a changing world”, and I wanted to make a window display to promote this event. We were given professionally-designed digital promotional material templates (poster, banner, flyers, postcards), so I used these as the jumping off point for the window display. I wanted there to be consistent branding across all our advertising.
I liked the orange corner with the pattern on it. I drew a similar pattern in Procreate and had it printed on legal size paper at a copy shop, then I cut out triangles and put them in some of the corners of the windows. I used the title and description from the promo materials and had those printed on small paper banners at a copy shop. I reinforced these with foam core so they would stand nicely. A QR code linked to the church website, where more information on the talk could be found.
The Inspiration:
The promo materials we were given had a circular image with a half-circle border around part of the image. This reminded me of a globe in a stand, which went with the “changing world” theme of the talk. I know that the DSCOVR satellite took several really good high-resolution images of the whole Earth, so I first thought about having one of those printed on a poster to hang in the window (the DSCOVR images are here!). But then I started to wonder, what’s the largest inflatable globe I could buy for a reasonable price? It turns out, the answer was 27″ in diameter. Our windows are about 48″ tall by about 100″ long, so 27″ seemed like it would be about the right scale. So, I bought it.
I was excited for the globe, but then I got to thinking, wouldn’t it be cool if it actually spun? I have a couple little models in my office on solar powered display stands that spin. I figured I could make something like that work, so I ordered a spinning display stand with a backup battery to supplement the solar power. Actually making it spin was easier said than done! The globe was pretty heavy for the little display stand motor to support, getting a 27″ diameter globe to balance on a rotating 4″ diameter stand was a challenge, and ultimately the display stand had too much slop in the motor shaft to make this work. After an evening of unsuccessfully trying to build a supplemental support structure for the rotating platform out of clear drinking straws, I realized that I just needed to hang the globe. I used fishing line to hang it, supporting almost all its weight from above and just barely resting it on the spinning display stand.
There was one problem with that–the fishing line that I used to hang the globe would twist itself up. It would reach a point where there was so much twist in the line, fighting against the motion of the motor, that the stored energy of the twisted line would win, causing the globe to spin rapidly in the reverse direction. Luckily, when the motor feels too much resistance it also just reverses direction. So, every ~20 minutes or so, the globe would reverse its direction of spin. We did once get a voicemail from someone passing by who called to correct the grammar in our window display–I was bracing myself for the call that the globe in our window was spinning in the wrong direction. Thankfully, nobody ever pointed it out!
I was explaining my annoyance at this to my parents one day, when my dad said that I should look into fishing swivels. I hadn’t heard of them, but they’re used to allow fishing lures to spin freely in the water without twisting the line. I got some and tried them, but the weight of the globe put too much tension on the mechanism so that it didn’t actually spin freely. It didn’t help. I declared defeat at that point and just let the globe reverse direction every ~20 minutes.
The display was a big hit with kids walking past. It was fun to see people stop and watch!
Upkeep:
Our window isn’t in an optimal position to get sunlight to the display stand, so it ran on battery power most of the time. I had to replace the battery once or twice per week.
The globe did lose air over time. After about three weeks I thought it was starting to look a bit saggy. I re-inflated it at that point and let it hang another three weeks or so as part of a second display.
Materials list:
The globe that I bought
The display stand that I bought
Fishing line
Fishing swivels
Final Thoughts:
Having a motorized display window was a lot of fun. The church members liked it, and often told me that they had seen families stopping to watch. It was fun for me to get to use a bit of engineering to make it all work. It did take a fair amount of trial and error, and therefore time, so it’s not the sort of thing that I can realistically do too often. I would like to keep stretching myself with projects like this now and then.