Model 3

For my third model I wanted to make an object that was presented in an interesting way. I made a base for a slot-joining piece to sit on, as though it was an object being presented in a museum or gallery.

The slotting piece was based on a leaf, but with more angular geometry distinctive of the deconstructivist era. The pieces are 4 mil thick with 4.5 mil slots. I found a 0.5 mil tolerance was sufficient during my tolerance testing.

The base piece consists of four curving sides with an ‘X’ shape between them for the slotting pieces to fit into. You can see better how it works in the assembly view below. The sides are, again, 4.5 mil apart, allowing the slotting piece to fit inside. I used the ‘loft’ tool in Inventor to generate the curved sides of the base piece – a tool I discovered while I was playing around in Inventor.

This is how it assembles:

Model 2

Developing from my first model, this design can join in two different places to generate two different forms. I took the basic pyramidal shape from my first model and added a cube cut-out in the centre of the pyramids. I learnt from my first model that it might be beneficial to make the holes .5 of a mil deeper than their respective cylinders so I added this extra depth into each hole. Hopefully it will now be flush when it fits together.

The two pyramids can be joined at the edges as they were in my first model, or can be joined at the cube cut-out, generating a pyramidal ‘diablo’ or hourglass sort of shape. I think these forms reflect the jagged-edged designs of the deconstructivist era, and the dual-functionality could be seen as the ‘unpredictability’ that is distinctive of the deconstructivist era.

 

The printed model was scaled down to save on materials and because of this it didn’t fit together perfectly. I tried to make sure the tolerance on the slots was 0.25 mil, enough for it to be able to fit together, and it just about fit.

Model 1

From my laser cut object I developed a more geometric shape based on my topic of deconstructivism.

Playing around with Inventor, I worked out how to generate my own working planes, thus allowing me to split a cube in half to make a pyramid. By combining 4 three-sided pyramids, I am able to make a larger four-sided pyramid.

The joining mechanism for this object is influenced by the cylindrical tolerance test I did earlier. On each piece is a 5 mil diameter cylinder poking 4 mil out and a 5.5 mil diameter hole 4 mil into the shape. When the pieces connect, the cylinder from one goes into the hole of the other and vice versa.

 

I was really happy with the quality of these prints. I didn’t need any supports under the pins – they stayed intact and are very accurate.

Te Tipunga

Te Tipunga, ‘the growth’, is the period of New Zealand history from 1300 AD to 1500 AD. It is characterised by the distinction of species due to hunting, deforestation, a change in climate due to the Little Ice Age and rapid human population growth (Anderson, Binney, and Harris, 83).

As Māori used up materials they were forced to make tools from new materials. An increase in abundance of woodworking chisels was seen, with many carvers favouring these more precise chisels over their previous large adzes (Anderson, Binney, and Harris, 87). These new tools brought about new opportunities for different designs and ornaments to be formed.

This cover for the bow of a canoe dates to around the fifteenth century. It was used to deflect waves as they came up over the front of the canoe. Its carved rows of lines, reflective of the East Polynesian art style, are combined with the “curvilinear forms of the late Māori era” (Anderson, Binney, and Harris, 73). Because Māori had new, more precise chisels, they were able to make smaller, more precise markings, thus sparking a change in the style of art to be more curved and spiralling.

Haumi (canoe bow cover)

 

Works cited:
Anderson, Atholl, Judith Binney, and Aroha Harris. Tangata Whenua: An Illustrated History, “Pieces of the Past AD 1200 – 1800”. Wellington: Bridget Williams Books, 2014. Print.

Haumi (canoe bow cover). Aotea Utanganui Museum of South Taranaki. Tangata Whenua: An Illustrated History. By Atholl Anderson, Judith Binney and Aroha Harris. Wellington: Bridget Williams Books, 2014. Print.

Tolerance Tests

This is the first of my 3D printed tests. Here I was testing slot-joint tolerance, to see how wide slots needed to be for two 5mil thick pieces to be able to fit together. I used 5.1, 5.2, 5.3, 5.4 and 5.5 wide slots, and I found that only the 5.5mil wide slots fit together. I was surprised by this; o.5 mil tolerance seemed like quite a lot. During my initial Inventor research/playing-around I worked out how to cut text into a shape, so I ‘engraved’ the slot joint sizes into the actual slotting piece.

My first print had the wrong settings (retraction was enabled) and I also scaled the object up in Cura, not in Netfabb, so it didn’t print very well. The printer made some odd noises and the plastic didn’t come consistently out of the printer so I aborted the print.The next day I scaled it up in Netfabb and checked my settings with Craig and it worked fine.

 

For my second test I was testing how a cylinder fitted into circular holes. I’d learnt from my last tolerance test that you needed quite a bit of extra room to get 3D printed objects to fit together so I made the holes 10.3, .4, .5, .6 and .7 mm wide, for a 10mm diameter cylinder to fit into.

The 10.5mm hole holds the cylinder in place firmly, while the 10.6mm hole allows it to pass through reasonably smoothly but without it accidentally falling out. The square piece printed well, except that for some reason it printed odd lines along the top. The outer shell of the cylinder didn’t print in the middle so the piece snapped. I don’t know why this was, but luckily I’d made the cylinder extra long so it didn’t matter too much.

My third test was of a joint I found in my initial research. The ‘edge lap’ joint has a hook on one side that locks over the other piece, keeping the join together. To un-join the pieces you simply prise the locking parts apart and slide the other piece out. I found this joint in the CNC Panel Joinery Notebook.

 

The print was very accurate and even. My two printed pieces joined very tightly together. I managed to push the two pieces together but I’ll need to use a screwdriver or some tool to pry them apart. If I made another one I’d make the locking piece slightly larger so it was not as tight a fit.

 

3D Digital Models

These are the digital models I’ve made in Inventor. I’d never used 3D CAD software before so I started off by making some simple geometric shapes and playing around with the software. I then combined shapes, putting them inside other shapes and cutting shapes away.

Object 1: Final

I decided to make my final laser cut object out of 4 mil poplar plywood. I like the look of the wood, and I thought clear acrylic would be too busy, what with all the slots involved. Because it’s a different material and thickness to the 3 mil corrugated cardboard I had been testing with, I had to do an initial test to determine the best width for the slots. The ideal thickness was 3.9 mil.

The final document took five minutes to cut. I nested the pieces on the document so I minimised wasted materials and so the document took less time to print.

The final object fit together very well, unlike the cardboard one which squished because it was a much softer material. I think it would be cool to make a slotting object like this, but with different sized pieces; something that mimics the look of a beehive.

Ancient Origins

In chapter one of Tangata Whenua: An Illustrated History, “Ancient Origins”, the authors talk of the history of the first humans to inhabit New Zealand, from their Southeast Asian origins in 3000 BC to the settlement of Māori in New Zealand, some 4300 years later. In the chapter, the authors use two images of carved wooden figures, one from Raivavae in the Austral Islands in French Polynesia, and the other from Ngāti Whakaue pā Pukeroa in the Rotorua district of New Zealand, to show “the continuity of artistic expression across Polynesia” (Anderson, Binney, and Harris, 19).

Art can be used to find out where the Māori came from. The two carved wooden figures look alike, both in their stance and in their ‘tattooing’. But because the one from New Zealand is later and from a different part of Polynesia, we can determine that the Māori must have come through French Polynesia to get here. In this way, we can trace back the Māori to their Southeast Asian origins and probably further back still, all with the analysis of art, language and culture.

Carved figure from Raivavae, Austral Islands

Carved figure from Ngāti Whakaue pā Pukeroa, Rotorua district

Works cited:
Anderson, Atholl, Judith Binney, and Aroha Harris. Tangata Whenua: An Illustrated History, “Ancient Origins”. Wellington: Bridget Williams Books, 2014. Print.

Female Diety. Carving. Pukaki Trust. Tangata Whenua: An Illustrated History. By Atholl Anderson, Judith Binney and Aroha Harris. Wellington: Bridget Williams Books, 2014. Print.

Te Whanoa, Taupua. Pukaki. Carving. Pukaki Trust. Tangata Whenua: An Illustrated History. By Atholl Anderson, Judith Binney and Aroha Harris. Wellington: Bridget Williams Books, 2014. Print.

Object 1: Iteration 4

I put the slots into the semicircular pieces, incorporating the corner-cutting technique I looked at in my initial laser cutting tests and first object iteration. I can think of one issue that might arise when printing this: the third smallest pieces that have seven slots should have nine, but the outer two will be very small. When I print it like this those pieces probably won’t fit together perfectly.

In the print document I added the two extra slots to those pieces so it should fit together properly.

Object 1: Iteration 2/3

I wanted the object to be half a sphere made of slotting pieces. However, I became very confused about how the size of each piece should relate to the one before it. I played around with some shapes and sizes but I just couldn’t get the right shape, until… 

A GIF of the process in Illustrator

… I realised that the sphere would simply be made up of half circles. I made a mockup of the object on illustrator with the pieces 20mm apart, but I thought this might be too far apart. To check I made a quick physical model out of paper that had the pieces 10mm apart. 10mm apart looked good.

To work out how wide the pieces should be, I used a birds eye view of the object (top left page in Illustrator). I simply copied the length of the lines into the width of the semicircular pieces, constraining the width and height proportions so as I changed the width, the height changed too.