New to Dome building, I am a home builder cabinet maker with a nice shop with lots of toys.
Looking to cover 26 round raised bed with domes for frost protection in the spring and fall.(Wisconsin).
The circles are 1828.8 mm (6''-6") OD and would like a 5/8 dome with the shortest measurement (flat side) to be 1828.8 mm not the points. Is it true the higher the frequency the rounder the dome?
Does the 1/8 bottom string start to taper back inwards? If so can I make them strait or flare out slightly so I can stack them for storage?
I do realize there will be thousands of pieces, no stranger to gigs and tedious work!
Thank you for any and all help in this matter, Cheers JD. email@example.com
[ Comments 6 ]
Something like this?
I must be missing something here, Somthing like what?
Hi JD, can you not see the diagrams, a three frequency 5/9th dome with a radius of 915mm. It doesn't wrap in on itself but I don't think you could stack them on top of each other.
Interesting project. What material did you have in mind for covering your mini-domes?
Putting a 3v dome over each circular bed is an enormous amount of work. Maybe use a 2v hemisphere with an antiprism riser wall. Other possibilities are a 2/3 icosahedron or a hemispheric 3v octahedral dome. The advantages of these is the lower number of struts compared with a 5/9ths, 3v icosa dome. Or if you’re really ambitious and love “geodiversity”, you could make several different types of domes.
Looking at your pic, here’s what I would suggest as a starting point. Buy yourself a few 100' rolls of 1/2" pvc flexible pipe. For the dome size you’re talking about, it has the right amount of flexibility for easy squashing and drilling of the strut ends, but is probably still stiff enough to make a solid 6 ft dome.
The idea is cut lengths of the plastic ubing as struts, squash the ends with a pair of pliers or clamp, drill a hole in each end, and then attach the various strut ends at each vertex using a bolt, nut and washers. So it’s a pipe dome, in this case using flexible pipe that will nevertheless still be pretty stiff at lengths of about 2 ft or less.
Another option for you is to dispense with the geodesics and go for a different type of dome – maybe 5 intersecting pipe arches, each with a single hub at the apex to collect the ends of all the curved supports. In that case, you stick the 10 “legs" of the dome into 10 of those concentric vertical pipes you’ve used as retaining walls (clever design you have there).
Or maybe you’re worried about the environmental or health impact of using pvc plastic, especially in a vegetable garden. In that case, you could use 1x2 spruce struts (stained for protection against UV) with a slot cut in each end. You buy small L- shaped metal brackets (1.5" per arm of the L). Stanley brand sells these in bags of 80 for about 20 Canadian cents per bracket. You bend the brackets to the correct axial angle (more or less) and then drive screws through the bracket holes to secure them to the centres of the strut ends. Then you proceed as you would for a pvc dome, installing bolts, nuts and washers.
Gerry in Quebec
About the 5 arcs method ... why not have them create a pentagonal opening at the top and cross over one another at angles to ground of about 60 degrees, with a couple of "binding rings" (like wooden barrel hoops) to hold it all together at the center and bottom ... I have built a model (see the attached picture
I'll try the pics again .. E:\kunden\homepages\13\d163207936\wsb4039380801\uploaded_files\