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How to Build a Geodesic Dome

Building FSSI 6V Dome
Step by Step Instructions on Building a Geodesic Dome Using Sonostar hardcore Geohubs
  1. Use the dome calculator to determine the correct length of the different size struts.  If you're using Sonostar standard or megahubs, you'll need to use Sonostar's calculator that automatically deducts the width of the hubs from the strut lengths.  If you use another calculator (Domerama or Desert Domes both have good ones), the lengths will likely be vertex-to-vertex, meaning there's no allowance given for hubs.  For standard hubs, the width to deduct from each strut is 2.28 inches.  For Megahubs, deduct 4" if you use a non-Sonostar calculator.
  2. The hubs were designed to be used with Schedule 40 PVC - available at almost any hardware or irrigation supply store.  Remember that 1/2" pipe refers to the inside diameter of the pipe and not the outside diameter which is actually about .84". That's important, because that's the diameter the hubs are made for.  For our metric friends, the .84" would refer to 21 mm, which is the outside diameter of the pipe you want to put into the standard hubs.  
  3. For Megahubs, there are two choices: If you insert the pipe into the hub arms, it's looking for 1" pvc pipe - which has an outside diameter of 3/4".  Why?  Because PVC pipe measurements are based on the airflow or waterflow through the pipe - so the inside diameter is what the store is measuring.  If you want to use 1 1/2" pipe to go around the hub arms (giving maximum strength), you'll need pipe that has an inside diameter of 1 1/2", which is exactly what the store will sell you if you ask for 1 1/2" PVC pipe.  The metric equivalents for megahubs is 31 mm for the inside diameter and 38 mm for the outside diameter.
  4. If you bought the Basic Kit, cut all your struts before you begin.  Use a PVC cutting tool to cut the pipe, or set up a cutoff saw.  You can also use a Skilsaw with a fine tooth blade, or a hack saw. 
  5. Color code all your struts with a stripe of colored electrical tape about 6” from either end.
  6. Follow the color coded map – we include a laminated copy that's weatherproof with every kit.
  7. Lay all your parts out beforehand and make a final count
  8. If you're glueing you dome together, have enough PVC primer and welding glue on hand to do the job.  Nothing worse than getting to the end and discovering you're out of glue.
  9. Apply primer to all your struts prior to beginning.
  10. Apply the PVC cement to either the struts or the hubs, or both.
  11. If you're using nuts & bolts, refer to the info sheet titled "Building a Sonostar Geodome using Nuts and Bolts".  There's a lot of useful information there.
  12. If your radius is more than 8’, be sure to have a ladder on hand.
  13. Build your dome on a flat surface, if possible.
  14. Start from the ground up, putting together all the perimeter pieces first.
  15. Make sure the curvature of the ground pieces is correct, with all the geohubs oriented in/out
  16. Push the struts all the way into the geohubs. Use a hard rubber mallet if available) to bump the struts to the end of the hubs.
  17. Mark your door location with an “X” on the struts that will be taken out (for the door), and then don’t glue them into the hubs. Once you get to the upper layers, you can remove them so you can go in and out.
  18. Lay out one row in advance and have someone else double check the color coding using the map guide. For you gluers, the welding cement sets up almost immediately, and you don’t want to mess up.  For you nuts & bolts
  19. Designate someone to be the photographer. It's fun to take pictures at every stage of building. Better yet, set up your cell phone with the time lapse function and it will record a video for you.
  20. PVC can get brittle when exposed to prolonged UV rays (like anywhere outside) A coat of spray paint will protect the pipes and the hubs.
  21. If you’re building a Frequency 6 dome, don’t confuse blue and turquoise, or red and pink - length struts. When you print out the map diagram, some printers make the colors look very similar. Always check the letter-codes for those colors , too.
  22. Have fun. Marvel at the genius who figured out all the geometry. Tell your friends what you’re doing, and let them help – it’s a lot more fun with more people helping.