Still winter, still tidying

I am still in hibernation mode, which means finishing projects off (like the desk) and tidying up (like the workshop).

Every so often, I think it is helpful to write down your goals in life. Currently, I only have two goals:

  1. Put things in boxes.
  2. Put labels on boxes.


So workshop now looks like:

For reference, this was a month ago, full of crap and a bloody big desk:

I know! Floor space! Sexy sexy floor space. I’m going to dance around naked stand in the middle of the void, stroking my chin and contemplating potentiality.

And if you think this is all a displacement activity to stop me from getting on with the Mitochondrion, Mark 5, then you’d be a little bit right. Still, I think I’ve worked out how to do the hard bit that was holding me up, so there can be progress on that too.

The very, very, very long tail of e-commerce

Three years after making it available, I have just sold my first 3D printed metal part:

It’s a replacement locking pin for a Triton Mk3 workstation. It retains the table when you shift modes from cross-cutting wood to ripping.

Clearly, either very few people are using Australian DIY equipment from the 1980s or that Triton owners are not complete idiots who lose their locking pins.

This says something about the long tail of e-commerce and how we will all do business in the Twenty-First Century. I’m just not quite sure that something is.

The desk

Finished the desk at the weekend. It took four of us to install, given the weight and close fit, and much scratching of heads and rehearsing to not leave gouges in the floor, walls, or ceiling.

I think that turned out not too bad.

Theraputic sharpening

When I’m under the weather, I potter about, fettling what needs fettling. That resulted in sharpening chisels and the hand plane.

(Click to enbiggen, if you’re really into scratch patterns.)

Plate of glass, emery paper, and a rolling jig. They’re not mirror-perfect, coz I’m not quite that obsessive, but decently sharp.

Turns out my phone makes a passable microscope, provided there’s enough light. Sadly, I did these last night. Now there’s sunshine I can now see the bits I missed, while not having the energy to fix them.

…still sanding…

And this is after I caved and bought a belt sander for the roughing, coz the wood is seventy year old macrocarpa and hard as.

This weekend, I will mostly be sanding this piece of wood

Yeah, and next weekend too.

The house is in this month’s New Zealand Life & Leisure

As ever, they’re focusing on the green roof. If you want an environmentally-friendly house, then a living roof is way down the list of things you can do. Insulation and double glazing are probably top of that list, but an article about a house with insulation and double glazing is not exactly going to get people to buy magazines.

Anyway, it’s two more pages pushing the idea that houses can sit lightly on the land and be warm and dry and healthy.

A living roof for the shed

I wanted to put a living roof on the shed, to match the house, to reduce the visual impact of the shed upon the neighbours, but mostly replace the natural habitat taken away by the shed.

The roof on the house has been just fine, although we have some weeding to do. For a shed, rather than a house, we could do something simpler, while using up left over wood and soil. To hold the soil against the slope of the roof, there is a wooden grid. To stop the soil washing away while still letting water drain, there is weed mat and holes bored in the horizontal grid members. I might have got carried away making the grid up, it really didn’t need angled pocket screws, but WTH. The grid is held in place by some stainless strapping over the roof edge and the handy nearby concrete wall.

I only want to build this once, so I want to do it right. That means making it strong enough and preventing corrosion… and the shed has a very flexible steel roof. Whoops.

The roof is going to be carrying about a quarter of a tonne of wet soil. On top of a wooden shed. In an earthquake zone. That’s not good and I don’t want all that coming down on someone’s head. Hence all the uprights in the shed have been at least doubled, there’s three more purlins, and rafters fitted every 400 mm. I used a deflection-limited approach to the structural design, which is a technical term meaning that I jumped up and down on top of it to see how much it flexed under 80 kg. It didn’t. And then after loading it up, I put a straight edge against to rafters to see how much they had bent. I couldn’t detect any bending, so I think it’s good.

As for corrosion, the shed roof is coloursteel, so half a mil steel, galvanised with lots of zincalume, and baked on paint. It’s warranted for fifteen years, even in salt spray zones. (Yes, we’re in a salt spray zone, despite being 150 metres up and three kilometres inland. We’re inland from Cook Strait, which is one of the roughest and windiest pieces of water in the world.) So it should be good, right? I mean, that’s what nearly every house in NZ uses… although it keeps plenty of people employed replacing roofs every few decades.

So first up, all the roofing nails got a coat of primer and epoxy paint. As did all the scratches that happened while installing the roof. Oh god, so many scratches…

Coloursteel is great if it gets to dry out every so often and the rain washes the crap off it on a regular basis. Sadly, it shouldn’t be used in contact with permanently wet materials or soil, which is a bit arse for a roof that’s going to be covered in soil. The steel roof is also going to be impossible to inspect for rust without digging up the plants, leading to a possibility of the whole thing collapsing on someone. So to keep it from rusting, there’s a layer of polythene directly on the steel, doubled over so that staples holding the top layer to the wood are separated from the steel by the bottom layer of the film.

For good measure, the top edge of the poly is also siliconed against the steel, to stop water running down between them. I probably should have put a flashing over that edge, but we’ll see how it goes.

The poly is protected by weed-mat, which also covers the drain holes in the horizontal parts of the grid.

For the plants, I ended up scratching my head somewhat. The micro-climate on the roof varies from sunny to shaded. It’s in a damp spot that gets plenty of rain, but with the thin (100 mm) soil it’ll vary from moist to very dry. And then there’s huge amounts of wind, coz this is Wellington. In the end, I just used Greater Wellington’s regional plants guide and chose the toughest natives from a bunch of ferns, low cover, and sedges.

From left to right: carex secta, carex virgata, hebe albicans, coprosma prostrata, asplenium gracillimum/hen & chicken fern, blechnum discolour/piupiu, muehlenbeckia complexa/puhuehue, coprosma acerosa, leptinella diocia, carex fagillifera, pratia angulata/panekenake. And then there were some extra leptinella from the house roof of a different kind, which seems to do very well in shady spots.

These ended up spread across the roof, with the ferns to the north in the shade of the tree and the sedges to the south where it’s more exposed. I’ve no idea what will survive, but plenty of weed mat and bark mulch should help.

Mostly, I like that from above you can barely see the shed at all. From the front, the sedges stick up over the roof and the coprosma should creep over the edge of the roof-line, helping the shed to blend in. And hopefully, it’ll last a good long time. Ask me in a decade or two how it’s going.

Things I screwed up:

  • If you don’t want anything to rust, use stainless fasteners, right? Nope. Stainless is good on its own, galvanised is good on its own, put the two together and you’ve made a battery. The zinc gets eaten by the stainless. The straps that stop the whole thing sliding down the roof are stainless and they’re screwed directly to the galv. Bother. I’m going to have to put some non-conductive plastic between them and replace the screws with plastic rivets.
  • I don’t think the weed mat will blow away, but we’ve a 120 k storm developing today, so I guess I’ll find out. I should have put some rocks around the edge.
  • I planted the tall sedges right next to the solar panel for the shed internal light. I’ve enough cable to raise the panel up by a metre or two, but that was dumb.

One hour camera stabiliser

Made from scrap to video performances at Raw last night. Worked pretty good to hold a Note 3 steady, while following aerialists, monsters, and … circ wheelers? Circists? Anyway, them.

The biggest drawback is that almost every face and edge of a phone is functional and therefore needs to be accessible, which makes it a bugger to clamp in place. This toe-strap worked ok, but I’d go for something that clamped from the other side next time. You know, when I want to put more than an hour into it.

No example videos right now though, coz vids are going to the performers first.

Sheddy Goodness

Most of our heating is solar, but wood for winter takes up space and we don’t have much, coz our land is not far off a cliff. We can grow a good chunk of our firewood on site, but that requires space two store wood for the two years it takes to dry.

We’d run out of space, so it was time for a shed. And of course, it has to fit functionally and aesthetically with the rest of the house, so this was more complicated than usual. I mean, the shed itself is bog standard kitset in cedar, but then there was carving out the space for it, the foundations for it, shelving to hold more than a tonne of wood, and reinforcement for the living roof, coz that’s going to be about a quarter tonne of soil.

And, of course, I only want to build this once, so I want to build it right and help it stay durable. Given the damp spot that it’s in, that’s going to be fun… Continue reading Sheddy Goodness

The last room in the house is nearly finished.

Painted ceiling, earth plaster, clay & lime wash, lawson cypress skirting from timber left over from the deck, poured earth floor.

Not shown: the huge amount of work this took from the both of us. But hey, nearly done.

Karl Polanyi’s “The Great Transformation”

Here’s a great article on Karl Polanyi, titled “Karl Polanyi Explains It All”.

If you’re trying to understand how the financial sector has become parasitic, why politicians have been bought, and how public debate has bcome so impoverised, then you won’t go wrong starting with Polanyi’s book “The Great Transformation”. It was written in 1943 and made the case for balancing the Market with the State. It laid out the reasons for the balanced social market economies that made the second half of the Twentieth Century into the best time to be alive, in all of human history.

If you want to understand why that has all turned around, then you’ll want to read Thomas Piketty’s update. As for what to do about the political imbalance between the rampant Market and the supine State, that’s harder. I asked that question in 2008, I’m still asking.

Further tidying and sorting out

The bag on the right is a Timbuk2 Classic messenger bag. I’ve had it for fifteen years and I’ve used it just about much every day. It has done pretty well but is starting to die.

The bag on the left is the replacement, also a Timbuk2 Classic messenger bag. I expect it to last a while.

Winter, therefore tidying up

Winter’s kicked in, so I’ve switched modes into finishing things off, tidying up, and getting generally tatted down and squared away.

So, the Too Bright Hat needed a new cable. 3-pin mini-XLRs seem to be the right balance of durable, small, and able to handle 8 Amps, but finding connectors with decent cable clamps took a while. The Hat is on my head and the driver is on my belt, so there’s plenty of flex and tension on the cable. Without clamps, that stress results in:

Ended up with the REAN Neutrik ones. Of course, no-one in NZ stocks them, which is a shame as they’re good and solid.

The Hat driver had a LiPo with just a fuze for protection, along with low Voltage cut-out handled by the Teensy, which is a bit shit. Charging the battery required taking the battery out of the box because it’s also kind of crowded in there and there’s no room for a charging port:

That yellow connector is an XT-60, good for sixty Amps, making it ten times as big as needed, and that black fuze is bloody huge too. So I swapped that all out for some EC3s and a proper PCM board, freeing up lots of space. Of course, I filled it right up with banana sockets for the charge and balance connections so I can charge the battery in place.

If I can do what I want to do with the Mitochondrion Mark 5, then it’ll be pulling peaks of 50 Amps. Inside a one inch tube. Fitting all that in is going to be fun…

Wellington on a good day

Three-up thigh shoulder stand thing

I saw a two-person version in that video that everyone watched this week and thought to myself, more looks feasible.

I have no idea what this move is called. It’s not in the three person sports acro list. I’m going to call it “Andrea & Wendy doing shoulder hand-stands on my thighs”.

It’s actually cake for the base but surprisingly bent for flyers.

Testing level shifters for running Adafruit NeoPixel strips from a 3.3 Volt Teensy

If you’re running NeoPixel LED strips off a Teensy 3, maybe because you want to put 180 LEDs on a hat, then you need a level shifter. But which one? The NeoPixel data protocol is high speed and pretty harsh on timing requirements and I’ve had a bugger of a time getting reliable data from the Teensy to these strips. Hence I’ve tested a bunch of shifters. I tried a TXS-0102, TXB-0108, 74HCT245, PCA9306, and a MOSFET based shifter.

The Teensy outputs data at 3.3 Volt, the strips expect 5 Volts. Or rather, the strips might see 3.3 Volts as a digital 1 or they might not. If you want some reliability, then you’re better off shifting the Voltage level up to 5.

Each LED reads the data it needs and passes on the rest, regenerating the signal to nice square pulses, so there is no decline in signal quality along the strip. Well, that’s the theory. In reality, all sorts of weird failure modes can happen.

Anyway, short conclusion from this testing is: use a TXS-0102 shifter if you’re tight on space and running one or two strips, use a 74HCT245 if you’re not or you are running three to eight strips. The 74HCT245 was the only shifter to give perfect performance, everything else had some kind of problem.

Test results and scope pics

180 LED Hat for Kiwiburn

Here’s details on my Kiwiburn project – a hat with 180 LEDs, all individually controlled… but to be honest, this was my project for Circulation, back in November. Getting it built was easy, getting it to work took quite some time, but I learnt a great deal. So here’s my design for a portable driver for the NeoPixel LED strips.

Why do this? Before making the next Mitochondrion, it was time to learn some new technologies.

The Mitochondrion Mark 4 (my glowstaff) is not too bad – 88 LEDs controlled by an Arduino Nano. However, it might be pretty but it isn’t responsive or interactive. It just splatters photons everywhere, generating randomly-chosen patterns.

I want more than just random brightly coloured lights. I want emotion, narrative depth, and engagement. That requires a far gruntier microcontroller than an 8-bit Arduino. Something like a Teensy 3.0 – ARM Cortex, 32 bit, about fifty times faster, lots more memory, and only 18 mm wide. And LED technology marches ever on, with Adafruit’s Neopixel strips being a big step up. And all of that is pushing me to use lithium batteries, even if they take more looking after than NiMH.

Thus it’s time to step up my technological game for the Mitochondrion Mark 5. The Hat seemed like a simple project that I could use for learning these new technologies – how to use them and what to use them for. Now that the Hat is working, I’m glad I took this step, because trying to get all this to work for the first time in the Mark 5 would be a bugger. Continue reading 180 LED Hat for Kiwiburn

Making firewood easier

We can grow maybe a third of the firewood we need on the land we have. Which is nice.

Obviously, the supply for each year depends upon which trees we’ll be trimming or felling. This spring, we got Joe in to trim back the big pohutukawa as it was overhanging the house and blocking the sun. That gave us a year’s worth of wood all by itself.

That’s a lot of bucking and splitting and stacking to do, maybe three cubes? I’m in favour of making this easier and safer, hence my three recommendations for firewood processing: the old car tyre, the bucking stand, and the maul handle protector. Continue reading Making firewood easier

Best Kiwiburn Ever!

Picture by Peter Jennings

Very brief summary:

  • Returning to Kiwiburn, with my closest people, who’ve also been away.
  • Helping to build and light the Effigy. The Effigy crew. The resulting meat blanket.
  • New site, oh yes.
  • Finally getting the Hat Band working and out in public. Ooo… it’s shiny. It lasted three days before an expected hardware failure.
  • Being really glad I’d put a dim mode on the Hat. Otherwise no-one could look at me, coz 180 LEDs. I’m not that anti-social. Well, not always.
  • All the smiles.
  • Poking nature with a stick.
  • Cuddle piles with all the fluff.
  • Being happy enough with the durability of the Mitochondrion that I can just give it to anyone, no matter how munted.
  • Realising that I’m very happy with my life.
  • No FOMO, but a bad case of FOMP – Fear Of Missing People. I didn’t see enough of far too many people, in some cases I didn’t see them at all, but as Wendy says we were “focused on deepening connections with people I already know rather than forming a whole bunch of new ones”

There’ll be a proper write-up of the Hat Band hardware, when I’m less shattered. And some pics and video.