CD-MATIC

Lampshade for Design Fringe........

 

Uses this black 3d printed centre piece......

which is repurposed here in the MKI CD-Matic

made mostly from makittoy

 

Hi

A few weeks ago, I was making a lampshade using some 3d printed bits I'd designed and made, and decided to play around with them a bit, and made a "thing" with the help of some Makittoy kits I have kicking around the kitchen. I had some left over bits of 6mm dowel which were used as the rods to connect the 2 sides, and the other rods and connectors were Makittoy.

It didn't really seem to have a use, so I put it on the kitchen table and used it to support a cylindrical Makittoy container. My girlfriend Mary, who'd seen me make the thing, later, and much to my delight - put some cd's on it. 

Aha - this is the killer app for this thing, and I made a small paper label for it saying K-Tel CD-Matic, something I stole (the K-tel bit) and made up (the CD-matic bit, somewhat reminiscent of the K-Tel Record Selecta)

And you know, being an engineer, just making a thing like that is not enough, I had to make it better, and drew and made some corner pieces for the new CD-matic, and replicated all the Makittoy rod lengths in 6mm dowel as a start on a new MKII Cd-Matic

Coincidentally at about the same I did Mary a demo of 3d printing by uploading some prints from thingiverse with the theme of Newfoundland dogs. (Yes, there is everything!) One design in particular (here) lent itself to printing in 2 colours to make the raised section at the top contrast with the lower base, and I managed to print off a few "Newfie" tags like that and pass them on to Mary.

So the "Newfie" tags got me using a technique I hadn't used before, and I decided to use it to make the labels for the Cd-matic. Its quite tricky swapping over colours in the printer as it takes a minute or two to cut the filament of the first colour, feed the second colour into the extruder, and for the extruder to start churning out the second colour, so my first attempt failed to have a second colour. Second and third attempts were better though, by the time I had started them I'd put in a wide border around the part which uses a bit more filament and makes the timing less critical.

With the new labels on, Cd-Matic was ready to go!

Nanotube tiling

 Hi

1

For a  while I've been making some sphere like things from cane, and these are actually twin edged platonic solids, and this draft article from this post about a year ago started to classify them. I've been learning more about them since, and in the last post made item 3.3 from the table above, a dodecahedron. I have also built 1.3, 3.3 (tetrahedron and cube and am now moving on to a version of 4.3.

2. Stylised / cutout forms of parallel face shapes.

So having built all the solid "platonic solid shapes" in the series (1.3. 2.3, 3.3) how about the planar one, 4.3? Its possibly the most interesting of all because in its rolled form (ie opposite edges of pic 4.3 are joined to form a circle)  it is the shape of a carbon nanotube. The wikipedia page and this article show the various forms of carbon nanotube, which are called "Armchair" and "Zigzag" and are flavoured by spirals. So before launching into making cane models, I decided to make 3d printed ones.  These will help me design and build the jigs for the cane versions.

The designs shown below can be made by 3d printing using the "hex" thingiverse file available here. (The file is a recent addition to the 3d printable construction set). First parts were printed, then they were assembled in sheets using orange 3d printer filament as pins between parts. Finally, sheets were rolled and edges were joined, again using 3d printer filament. Sheets could be Zigzag or Armchair. Plain joining created cylinders while displaced joining created spirals.

All the rolled parts have a resistance to rolling created by conflicting surfaces within the structures. This is something already observed and explained in non-hexagonal cylinders, see the pdf available on the thingiverse page.

3. Plain zigzag (style nanotube model)

4. Compatibility of hexagon with other pieces from the Thingiverse set. Parts at the top are the small equisided triangle.

5. Zigzag with spiral

6. Zigzag before rolling. (the top edge is zigzag)

7. Armchair before rolling (the top edge is armchair)

8. Plain Armchair

9. Armchair with spiral

Update July 6

10. Cad model for central jig for cane model nanotube. Aiming to print this within a few days. It is....

11 derived from the red / central jig seen here being used to make an octohedron. The shape is 5.3 in the table shown at the top

I've now designed a jig to make a cane model of a nanotube. The tiling nanotube pics on this page have helped me work out what to build and how to build it. I will start with the zigzag cylinder as modelled in 3. More blog posts to follow.

Now that I've done one hex shape, I can see the sense in doing another hex and 2 pentagons to fill in the gaps in the construction kit. When time allows!

PS: as a reference for the Nanotubes, here are 2 pages from Noel Graham's excellent book "Mathematics with Geoshapes", published in 1998.

12

13

Twin Edged Dodecahedron

 

1 Almost there! Bamboo is clipped to jigs while superglue is applied to attach bamboo pieces to each other.

2 Later the jigs were removed and the whole thing stays together

These are some steps in making the plan: above is a dodecahedron net altered to show where "crossing" connections between faces should occur, below is a stereographic projection equivalent showing the numbering of nodes (1-20 purple) and the path of the bamboo through the nodes (1 - 60 black )

4, Done

5. Starting off: assigning node numbers using the plan.

6 The full set of central jigs for this polyhedron style, top to bottom are dodecahedron, icosahedron, cube, octahedron, tetrahedron hard to see in black.

7 Cube made using the same technique.

Hi

For a few days now I have been gathering parts to make a twin edged dodecahedron from a single knot.  I've known this is possible for a while, and have had the basic parts to make it designed and  / or on hand for a while. The key parts are a 20 sided 3d printed jig which holds m6 althread rod ( I have made these for all the Platonic solids, see 6 above) and a node jig to which bamboo rod can be clipped. 

There was quite a bit of work, designing the pattern, sawing allthread rod, attaching it to the centre piece, attaching and numbering jigs, then attaching and glueing bamboo, and finally jig disassembly.

I'm finishing writing an article on these, for the current draft version, see here , and I have done a few blog posts such as this as well. Bit of a slog getting the article finished as its all computer work and not the light relief construction brings.

regards steve nurse

Update June 4

With the full jig available and ready to go, I thought it a pity not to keep going and make a few more dodecahedrons. This time I planned for a different switching arrangement (see article in link above) with 6 twin -  circle elements made of cane, each in a sort - of figure of 8 pattern. One of these is finished now and I plan to make one more. The one I have made uses 6 3d printed plates to contain and tidy up all the basket cane loose ends. 

The 2mm basket cane I use came from a marine supplier. The bundles have to be separated into strands, and the strands are just long enough to make the figures of 8. Mary took some of the pictures.

Update June 26

I have now almost finished 2 lamps for the exhibition  " design fringe ". Some of the diagrams presented above have been used to decorate the shade. The bottom diagram was shown above but now includes a couple a new feature which shows where the path for the cane is predetermined, and there's no need to look at the guide to work out the next step. Firstly, the path is determined by the numbers in circles where the node numers mtch up with the step numbers. This breaks down after a while, but then later if one potential side of the cane's path is occupied it has to go through the other - this is shown by squares around numbers.

Pollution from Golf Tees

 

Golf tee remover (left) and golf tee (right)

Hi

For part of this year, I have been engaged with finding golf balls washed up on and in our local river bank, and making art and structures with them, for example here. A chance sighting of a random golf tee had me thinking "are golf balls the only direct pollution caused by golfing?", and the answer seems to be a resounding "no".

Golf tees (small platform for raising a golf ball above the grass, so it can be hit more easily) seem to be another source of pollution from golf courses. About 7 (see here) tees can be broken per round of golf. Some of these are made from plastic, but some from biodegradeable organic materials , while others are designed not to break and therefore should never be left behind. Whatever the tee, they are likely to float and so take a different path to golf balls when washed away. Bouyant tees seem more likely to float away and reach the open ocean than golf balls which sink.

The harm golf tees cause in the ocean has been documented anecdotally, but a widespread survey would be hard to do and involve examining the gut contents of thousands of birds and sea creatures to reach scientific conclusions. Nevertheless, some anecdotal evidence is strong such as: 

Golf tees and other plastic pollution implicated in seabird deaths, Los Angeles Times, 2006 

Shearwater bird ingested golf tee, Papers and Proceedings of the Royal Society o/Tasmania, Volume 142(1), 2008

Turtle ingested golf tee, A citizen's guide to plastics in the ocean: more than a litter problem, 1988

Beachcomber Matt is on Instagram and is a UK collector of ocean pollution, who picks up golf tees and other pollution and uses the hashtag #golfteeatsea  . As well as golf tee pollution, he has recently highlighted Australia's recent banning of disposable vapes as a good move. That is not for the health of Australians but the health of the planet!  We just don't need more plastic crap (disposable vapes) that end up as non-recycled items in rubbish and in the rivers and oceans.

An Australian golf publication recently reported on golf tee pollution issues and posted about a club banning plastic tees. It would be good if more golf courses followed their lead, better still, Australia could ban plastic golf tees.

Regards

Steve Nurse

 

Foiling Surfboards and Alt Surf

 Hi

 This is an article which originally appeared in the June 2021 issue of Huff,  the magazine of OzHPV inc. which I write for and edit. So this article went out to subscribers only, but I thought I would drag it out for all to see. Since it was written, the term Alt Surf has been coined for some of the different craft described below. So - um - please enjoy my writing from a few years ago. It has fairly basic layout at the moment and I will go in later and see if I can improve things.

Regards

Steve Nurse

 

Caspar Steinfath

Earlier this year, Casper Steinfath piloted a paddled foiling watercraft successfully across 120k of sea between Denmark and Sweden. Foiling is a bit like flying, with an underwater wing lifting most of a watercraft into the air, and away from the surface of the water. It marks an achievement for this type of craft and its pilot, and I decided to try to do an explainer for Huff.

 Caspar’s achievement came to my attention through a surfing website, Magic Seaweed. Although mainly to do with surfing and surf forecasts, surf sites like Seaweed cover all sorts of craft that make their way into the waves.  

 

Surfing itself started as a hybrid of arm paddling and wind energy. Wind conditions at sea give rise to ocean waves, and they are an accumulation of offshore weather. But these days many combinations of human, natural and machine energy count as surfing. There are stand-up paddle boards, wave pools with machine generated waves, foiling surfboards, kitesurfers, wingsurfers, windsurfers, electric surfboards, and surfboards towed into waves by jetskis. Foiling is quite a small part, but when famous surfers go foiling it is reported, videoed and seen, for example this video of surfing champion John-John Florence foiling as if by magic. The foils are supported on undersea currents, and sometimes these are parts of unbroken and invisible waves out at sea.

 

Alan Abbott prone / head forward streamliner.

 

Alec Brooke recumbent streamliner

 

Human powered foiling started in 1983, when some the first human powered hydrofoils were built and ridden by Alan Abbott and Alec Brooks.  A few years earlier, Bradham Brewster had researched and written about the possibility of the hydrofoils in a mechanical engineering thesis , and Abbott and Brooks took up the challenge of building a foiling watercraft. All had been involved with one of the fathers of the modern human powered vehicle movement, David Gordon Wilson, and Abbott and Brooks had both built streamliners for human powered land speed competitions. Alan Abbott also piloted record breaking bicycles which were ridden in the slipstream of cars.

Flying Fish 1

 

Flying Fish 2

Research into human powered hydrofoils was initially done by towing the submerged wings that would provide lift, allowing the powering propulsion and the underwater wings to be developed separately. Abbott and Brook’s first hydrofoil, Flying Fish 1 didn’t float, while their 2^nd, Flying Fish 2 floated on catamaran pontoons. The website for Abbott and Brook’s machines is http://flyingfishhydrofoil.com/ while http://human-powered-hydrofoils.com/ shows some machines that have been developed since. Commercial human powered hydrofoils have been slow to come, and some of the first were driven by pumping the legs up and down. An example is the Aquaskipper which was for sale on Amazon. The Manta5 from New Zealand is a current ebike hydrofoil which costs around $9000 and brings the effort of human powered foiling down a notch or two. And solar powered hydrofoiling is now a sport, with the Netherland’s TU Delft (who also have a speedbike team) competing.

 

Aquaskipper foiling craft

, 

Solar Electric Foiling craft

 

 Laird Hamilton pioneered the surfing version of hydrofoiling which was introduced in the 2003 film Set Into Liquid. A group of surfers, waterskiers, windsurfers and sailors developed the sport from a range of equipment. In this history of surfing hydrofoiling, the human powered versions of hydrofoils don’t even rate a mention, but having access to waterski foils from Airchair seems to have been a key step.

 

Manta 5

 

Manta 5 information showing power requirements for foiling: human and electric power

 

Hydrofoil surfboards now seem to be the most popular form of human powered hydrofoiling. The natural power elements can be wind from kites or handheld sails or ocean waves or currents. The human powered component can be stand-up paddling or a similar pumping technique to the Aquaskipper. But unlike the Aquaskipper, the newer surfboard hydrofoils follow the templates of surfboards and windsurfers, so aren’t seen as clunky machines. It looks like they’re here to stay, and the machines are modular with different foils, boards, paddles, inflatable wings, sails and kites going together to make a full kit.

Wingfoiling. photo courtesy Sailing World

 

This article really only skims the surface of the topic, but the area seemed too interesting not to mention. We’d love to hear more from Huff readers.