12-20-2010 Latest Design Work on the Joist Hanger for the Hubs
12-8-2010 Some Additional Work on the Complexly-Curved Green Roof Studio
12-6-2010 Framing Design for a Green Curved-Roof Studio
10-12-2010 Quick Light Design for a Contest by i.Materialise.com
8-19-2010 Where I'd Like to Head with These
I'm going to need to develop my PhotoShop skills.
8-18-2010 Last of the TRD-based Sculptural Shapes (for now)
8-17-2010 More TRD-based Sculptural Shapes
Four times the starting number of TRDs
8-16-2010 More Experiments with TRD-based Sculptural Shapes
8-15-2010 Some Experiments with TRD-based Sculptural Shapes
Thinking of images for another crop of note cards for holiday gifts.
8-5-2010 Slow and Steady...Small Steps
I've decided to continue working on this model but as a long-term project. I'll add to it as ideas occur to me.
8-3-2010 A Little Night Render
Really struggling with this. Not the model or the render, just whether I should be be spending time on it.
8-1-2010 Fusing Traditional with Curved Architecture
The sense that I might actually be able to build curved-roof structures has me interested in creating models again.
7-28-2010 Aluminum Hub Concept Model
Recently realized that with stock aluminum tubing and extrusions I could create hubs quite easily. This image shows how. The white pins represent bolts.
5-15-2010 Bamboo/Hemp Space Frame Prototype
Recently I tried creating a space frame with 1" bamboo, 1/2" hemp rope, wire ties, and 3/4" screws. I'm sorry to report that the prototype didn't perform as I had hoped. The problem is that the hemp hubs don't work well. They have too much flexibility and it is difficult to connect all the bamboo rods coming into each hub. It seems clear to me now that whatever is used for hubs must be strong and capable of holding the spokes connecting to them at their given angular positions. Most likely metal hubs would be needed.
I've pretty much come to the conclusion that this approach is not a productive line of inquiry. In essence it doesn't make use of the natural strengths of bamboo and hemp. If I continue experimenting I'll go back to using pipe segments for hubs and probably plywood for the spokes.
12-21-2009 Bamboo/Hemp Hub
I'm fascinated by bamboo as a building material, as in much of the world it is readily available, inexpensive and its use is sustainable.
Recently it occurred to me that bamboo could be used in space frame like structures by using hemp rope (another sustainable material) for the hubs and bamboo for the spokes.
The images below show a prototype hub. I'm using a heavy duty wire tie to hold the hemp rope pieces together but wire or twine would work just as well or better. I use screws to secure the rope in the bamboo ends but again, I'm certain solutions using locally available materials could be developed. I think it is pretty cool that a curved space frame structure could -at least in theory- be totally constructed from organic inexpensive locally produced materials.
12-21-2009 Snow on the Shed
I was quite curious how the shed would look with a smooth covering of snow. The recent snowstorm provided an answer.
11-18-2009 My Curved-Roof Kayak Shed
Having built the grid shell/curved space frame roof structure I of course had to do something with it. One can't just leave these things sitting in the driveway. The neighbors start to get upset. So after much pondering I decided the easiest thing would be to create a little shed for the kayaks. With a lot of help from the family, and after a spectacular failure on the first erection attempt, it now sits happily protecting the kayaks.
9-7-2009 Adding Roofing to the Grid Shell / Curved Space Frame
With lots of help from my son Robin we finished cutting and attaching the triangles to the roof frame yesterday. The approach I'd figured out for cutting the triangles worked beautifully. It is a bit tedious but it creates triangles that fit perfectly on their triangular frames. OK, not perfectly, but well within the tolerances needed. Following are four images. One taken at the start, one with just one triangle left, one with all the triangles attached, and one shot of the underside.
If I were to make more of these I would want a better solution for the hubs. My current thinking is that short sections of steel pipe would be a good replacement for the PVC pipe sections. However, to use steel pipe some sort of joist hanger is needed to hang the beams from the pipe. The following two images illustrate what I have in mind. If you happen to know of any such product please send along the information.
Looking Down from Top
Looking Up from the Bottom
8-26-2009 Curved Space Frames Using SketchUp
I spent a fair amount of time this summer thinking about curved space frames, a topic near and dear to my heart. My goal is to have a framing system that will support building highly curved roofs. I had what I believe is a bit of breakthrough a few weeks ago. Up to now I've been thinking of the framing system as being basically a shell. The breakthrough was the realization that by giving the curved framing significant depth -either via a truss system or just through deep joists- that the roof framing becomes much stronger and a number of other issues related to the edges get resolved nicely.
Throughout my exploration of this subject I've used SketchUp to investigate ideas and to design models to test. The models in the image below have been the basis for most of my experimentation.
The two straw and pipe cleaner models in the next two images helped me develop the idea of a curved space frame.
These led me to realize that I could take a curved TIN dome-like surface and give it depth as shown in the next image.
Note the diagonals on many of the joists. It was while playing with this model that I realized I could just use deep joists instead of trusses.
The final piece I needed to fall into place to actually build this structure was a reasonably easy to create and use hub. It popped into my head that a section of 2" PVC pipe might do the trick. Some experimentation confirmed that the PVC pipe was strong enough for a prototype.
I next had to figure out how to incorporate the pipe hubs into the SketchUp model. Strong SketchUp skills proved very helpful for this task and I was able to solve this problem fairly quickly. The following images show my approach, and hint at the large number of measurements that need to be taken off the SketchUp model.
With the model, some PVC hubs, 1x6 pine joists, and a bunch of drywall screws I was able to create the structure shown in the images below.
The prototype frame is finished and came out quite well given all the things I had to figure out while constructing it.
While constructing the frame I kept thinking there has to be an easier way and I have an idea for a connector -basically a joist hanger that would hang down from the upper edge of the vertical pipe section- which I believe would make building these much easier.
The frame is very strong. I weigh 200 lbs and can stand on top of it and there is no perceivable deflection. There is definitely some potential here for creating highly-curved roofing structures.