Instructables

Step 2: Making hubs

Picture of Making hubs
The hubs are the most difficult, time consuming, and critical part of the dome. The hub design consists of PVC tabs, bolted together to make a strong and flexible connector between the struts.

The use of schedule 40 pipe is important. Class 200 cannot handle the stress of holding the dome together without breaking. Schedule 40 is flexible enough to allow the dome to be built without bending precise angles, but strong enough to keep from breaking.

You need to make:
10      4-way hubs
6        5-way hubs
10      6-way hubs

You will need:
130    4" pieces of 1" schedule 40 PVC
130    couplings
26      1/4" x 2" hex-head bolts
26      1/4 hex nuts
52      1/4 washers

 
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mhamshar3 years ago
something doesn't add up you say you need 30' of schedule 40 PVC. but you say that you need 130 4" pieces. 130 x 4 = 520 520/12= 43 1/3' . or am i reading something wrong. thanks in advance