If you are a Hackaday reader, you probably like space in real life, fiction, or both. A trip to a planetarium is a great treat, but what if you could have a planetarium in your backyard? [Ecasill] thought so and used a Zip Tie domes kit to create just such a thing. It takes some sewing and a projector, but there’s a problem. The dome needs to come down if there is going to be bad weather. The answer? Magnetic dowel rods.
Because the magnets are brittle, plastic dip covers them after epoxy sticks them in place. The cloth has steel bolts to adhere, too. All in, the setup cost about $2,000. That includes a projector, a mirror ball, a sound system, and all the construction.
There were a few items that need improvement. In particular, [Ecasill] wants to use Velcro to tighten up the dome fabric to make it smoother. We were impressed with the dome construction and the clever use of magnets. If you didn’t want a planetarium, you might be able to use this idea as a makeshift observatory or some other backyard structure.
The projector has to, paradoxically, project to a small area big enough for a mirrored ball. [Ecasill] provides a link to the site that gives all the information and software about setting up such a projector.
This isn’t the first planetarium we’ve seen. A lot of planetariums do as many laser shows as space shows and you could do that, too.
Could be made even cheaper sturdy enough to resist bad weather.
– Slatted frames can be found for free from the dumpster. Gather a bunch of these, and unmount the slats.
– A simple varnish will protect them from the rain. If you´re fancy and have time+funds, wrap them in glassfiber+epoxy.
– Then all you need is to shorten them at the same size, group them by width/thickness, use the strongest ones for the base, drill holes at the ends
– visit the hardware store for large washers, bolts, nuts. Screw everything together.
That flexible yet incredibly robust construction should last years, even in the rain/snow/ice and strong wind. Would resist a hurricane is sufficiently anchored.
This is just a giant GeoMag kit then?
My thoughts exactly! As chance would have it, i found a GeoMag set in a dumpster yesterday. Cool toy for sure.
I like space.
Sorry, can’t help my self… https://www.youtube.com/watch?v=rRi8LptvFZY
Looks like the fabric is a few sizes too large… the sagging is really killing the effect IMO. Could be fixed with a little cutting and re-stitching.
Use a blower to inflate it.
SAYOK Portable Inflatable Planetarium Projection Dome Tent for School with Air Blower and PVC Floor Mat on Amazon
https://a.co/d/h7vM2HS
Here’s a good source for a first surface, half dome mirror:
http://www.duravision.net/
This was the quote they gave me a couple months ago:
NZ$595 for a single mirror. If two or more are purchased the cost price is NZ$475 each ex works. This price does not include freight. Freight quote for 1 mirror to San Diego, USA is NZ$332.