Monday, 18 October 2021

52t Clock

 






Hinge pins on production line

Hinge assemblies

Hi

A while ago, I made a tetrahedron clock from some old bicycle disc brakes. It all went together, and I thought I could donate it at a prize at a bike event. But one bicycle-themed clock trophy would not be enough, as I would want to donate a trophy for male and female winners. 

So I've been fossicking in my bike junk and cd-rom piles and have gathered together a few suitable candidates for the next clock, and then in the last day or so have put it together. 

The new tetrahedron has 2 sides which are upcycled 52 tooth bicycle chainrings, and 2 which are upcycled timber chainring guards, which are shown in my bikes blog posts such as this one. I trimmed the timber guards in the lathe, something I've never done before, but it worked ok this time.

Anyway, it all came together well, although the clock isn't actually telling the time properly yet.

The image on the cd is a little thing Leonardo Da Vinci whipped up called Vitruvian Man. On the cd he is already poorly treated by being chopped in half and placed in a bicycle sprocket, and looking at the photos, I realized I had mistreated him again by giving him blue tracky dacks to wear!

Personally I like it! A trophy that doesn't take itself too seriously.

Update October 19

This morning I've taken the clock apart to fix the mechanism (I think the rubber bands used to hold the edge joiners in place are straining it too much) and realised the clock looks perfectly fine with just the cd and one chainring as below. Its a bit less complicated that way. Anyway, no need to make a decision yet as to which way to present it.


Regards

Steve Nurse

Tuesday, 12 October 2021

Mylar constructions

 

With tools, a paper cutting guillotine and Mylar, and m3 nylon fasteners...


made this, a

cube / octahedron, which is now...

with all the other dangly things outside the kitchen window.

View from below. It's held up by a bicycle gear cable, and a nylon nut is a meant to be a low-friction bearing.


Hi

A few weeks ago, I made some cantellated forms from playing cards, and realised that the designs could be taken further, or even moved outside if they were made of different material. I had a roll of Mylar material left over from my time as an engineer at CMG / Regal in Rowville. The plastic film goes between steel laminations and copper wires to stop fires and other disasters happening.

Anyhow to go with the mylar I wanted some plastic fasteners, so bought m3 nylon nuts and bolts through ebay. They all took a while to arrive, but I was quite grateful for the think time before starting to make more things. Finally I got motivated, and made what you see in the photos above. The equatorial panels are folded on one edge to catch the wind, and rotate in the wind.

But no rotation to date, it hasn't been windy, and the fan bits aren't very big, so I can redesign if necessary.

Anyway very pleased with the way the photos came out, I like the transparency of the mobile, and there will be more to follow.

 Update October 16, 2021

New layout with extended fans. Just visible here is a map of Australia in outline, put in by piercing the Mylar with a centre punch.

Globe features now include rotating on a vertical axis, and Australia in the Southern Hemisphere. And fragility.

Settled on an Australian map showing Aboriginal Australia. It has been this way for the last 50,000 years or so with the exception of the last 300 or so.


I did a bit of rearranging of cube / octahedon and have now christened it a globe. By extending the fan blades compared to the top photos, and also adding  string to the bicycle gear cable, the globe now rotates and sways with gay abandon. Very pleased, and I plan to make a few more versions. Here is a short video, it moves quite nicely.

Regards  Steve Nurse