Sunday 4 November 2012

Prep to Prototype

On the way to prototyping my ducted wind turbine design, there have been a few silly setbacks as usual with 3D printing, and that's before even mentioning how awkward part sourcing is when no one supplier ever has everything you need, and I end up forced to waste postage on a few orders just to get electronics to build a data-logging controller with. Also I'm writing this for a second time since Blogger ate my post by erroneously bringing up a blank workspace one morning after I was 90% through this post, and saving over it before I could close the tab. Unlike those lovely etherpads, there was no writing history to revert back to.

I've brought this reprap to its working limits in a couple of different ways over the last few weeks, firstly with a bespoke drill-guide that I made in a similar way to the dremel cutting kit only super-sized so as to allow a cheap hammer drill to make nicely perpendicular holes in the absence of a drill press.
A trouble with this print is its huge width compared to the narrow surface area actually in contact with the print surface, which meant that, being a PLA prototype, it could barely adhere to the kapton-taped surface strongly enough to stay down. When some overhanging edges started to curl up slightly, the resulting light collisions with the extruder head caused the wider of two parts to start lifting up off the printbed with an audible crack. I found a quick fix to keep that part in place before the whole surface dislodged.
Bulldog clips and small allen keys were handy, so they held the part down.
This print was eventually successful, but not before another limit in size surprised me.

Tuesday 4 September 2012

Practical Plants

A new website launched in the last month that could be a powerful tool for Permaculture designers worldwide. At Practical Plants, produced by a web developer and a writer who are together also building an organic farm in northern Spain, the huge database provided by Plants For A Future has been forked in a wiki format, while retaining database-search functionality and adding a beautifully-styled new interface, so that hopefully the information brought from that old database can be improved by weeding out inaccurate or incomplete information and using better sources.
Practical Plants beta homepage
While PFAF has primarily focused on species appropriate for a temperate climate, Practical Plants aims to cover information on species in all climates on Earth, while adding other useful structural information to the database such as companion-planting guilds. Various practical uses of each plant will now be linked clearly to relevant parts of the plant, for instance to help people avoid eating unpalatable or toxic bits of some plants. This extra structure needs some tidying to install though since it wasn't already in the existing database structure, so why not help out when you have a moment?

Thursday 16 August 2012

Every Sheep Has a Silver Lining

With the Elaeagnus shrubs that suffered greatly after I planted them outdoors a few months ago, for a pair of evergreen species to lose most of their leaves during spring, I was understandably worried that they would die due to root shock and waterlogged soil.
What's more, they seemed to be completely over-run by local 'weeds' to the point that I couldn't see this one.

However, since the tiny forest garden that I'm pioneering was slightly chewed up by marauding sheep a couple of weeks ago, I've spotted signs that they are getting some strength back, and noticed some of the other plants that I stuck out growing vigorously.

Saturday 11 August 2012

Printing PLA on Paper

A few days ago I started doing tests of 3D-printing PLA using paper as a build surface, since I previously saw it briefly trialled with some success.

My first test mimiced Doxin's test by simply using cheap white A4 printer paper. The first things that I tested printing on the plate were: a new and more robust axle support for my spool stand, and a couple of the ball-joint pole-end-caps for EFFALO's 2V geodesic dome connector set. The paper wasn't clamped down very well since I could only find 4 bulldog clips at the time, and had wrinkled up either end of the paper slightly when attempting to clip it with its longest side in the X-axis before settling on having it along the Y-axis.
Paper set up for first test.

Saturday 4 August 2012

Lessons in Rapid Prototyping and Design

Never before did I realise what a huge difference software and firmware can make to 3D-print quality.

Not long after setting my reprap up again in its new home, I found it having problems moving in the Z-axis, where the motors would refuse to move half the time, which after describing it on IRC people helped me figure out that the controller was telling the motors to accelerate too fast.
The acceleration that had been implemented in June 2011 Sprinter firmware still caused a significant amount of 'jerkiness' in axis movements. By updating to the latest version for June 2012, not only did more appropriate acceleration, adjusted by a predictive 'look-ahead' buffer, improve this current problem, but it also cut out a vibration problem that broke my Y-axis last year, by pausing at the end of each move for a few ms, when making very short successive movements in order to draw a narrow zig-zag fill line. This helps because in most stepper-motor use there is no feedback control mechanism - the idea being to move a set number of steps then lock in place and hope for the best, which in reality can result in nasty vibrations. By stopping for a moment, the transient vibrations resulting from overshoot can settle, so there is less chance of them feeding into some resonant frequency and shaking the printer to bits.
Illustration of overshoot, via Wikimedia Commons.

In the new firmware a minimum temperature is now set by default, which might have prevented another previous incident that I had with over-heating when a thermistor connection broke.

Friday 3 August 2012

It Hits The Fan

Gardening in a region where you're almost always surrounded by sheep has its obvious pitfalls...
Sometimes those sheep or their mischievous little lambs find a way past the fences you put up, because they can see that not only is the grass greener on the other side, but there are also tasty things other than grass to chew on.

One or more of those sheep got over a fence recently and wreaked havoc among the crops I'd planted, trampling some while eating the tops off others...
They seem to love eating fiddleneck flowers

Saturday 23 June 2012

Confluence of Aspirations

On locally appropriate crops, some Alpine Strawberries that I planted out along the swale wall from pots are doing fine, and I hope to give them some rhubarb in between for company soon by separating some of the rhubarb that's already growing around here.
This Alpine Strawberry plant is just going through flowers and starting to grow fruit at the same time.

Friday 1 June 2012

Flora and Fauna Identification in Sutherland

In this post I will try to identify many of the seedlings and volunteers/'weeds' that I have seen growing well around my local area in the cool maritime climate of Sutherland, around the North/West coast of Scotland. Your help is greatly desired, so please leave a comment if you have a clue! This post will be updated until I consider it reasonably complete. (Last updated 1/7/12)

As for local flora, daisies, dandelions, nettles and heather (all with edible parts) are so ubiquitous around grassy areas here that there's no point wasting a photograph on them. Seriously, this last month I've seen a whole sheep field turn white with daisies, mowed lawns shine bright yellow with dandelions, everyone on this island has probably seen how nettles like to take over any odd nook or slope where moisture gathers, and heather... well let me just say that every few years the sheep farmers set entire hillsides ablaze up here to get rid of the stuff after it has taken over; some of the current google maps satellite images for the region still show glowing patches and smoke clouds at low levels of detail.

Most plants here suffer salt-burn from the coastal winds if not well protected, especially trees:
This is a native Rowan tree, known for producing a quite tart fruit similar to cranberries only much more sour, typically used to make jellies to accompany meat, otherwise a great bird food when left on the tree. It probably prefers to be further inland though.

Sunday 20 May 2012

Sowing Perennials Indoors

Progress was slow over the last few weeks; I lost a lot of work time looking after a friend's hungry hair-generating quadruped for them while they were away (I'm getting a bit tired of the number of animals people feed with agricultural produce when this society won't even distribute it to all humans, can you tell?), but I have learned some more about what works in this region in the meantime.
Most of the fruit trees have started blooming, this damson tree was the earliest.

Sunday 8 April 2012

Did you say shrubberies?

As I mentioned a few days ago, the elaeagnus pungens shrub that I planted from a pot looked quite unhealthy, since most of its leaves were turning pale and some dropping off though it should be an evergreen plant. The hybrid Elaeagnus x Ebbingei from a pot was doing very well by comparison:
Although a few of the leaves were turning that same way.

Tuesday 3 April 2012

A Brief Update

I hate moving house.

Some of the elaeagnus shrubs are struggling here.
Snow in April.
That is all.

Wednesday 7 March 2012

Supporting Trees

Recently I noticed a quite old mini-documentary on forest gardening that I thought I had seen before, but hadn't as it turns out, having just seen a separate interview with one old fellow in it, the late Robert Hart, who started a quite famous forest garden halfway down England in Shropshire. This documentary was made up of a series of 3 interviews, which it turns out contain some great gems of knowledge on forest gardening in a temperate climate; the first being with Robert Hart about his 500m^2 labour of love, the second was with Ken Fern, who started and continues to maintain Plants For A Future, a project in Cornwall that has trialled thousands of different plants for their suitability in temperate climates, creating a database with detailed information and ratings based on things like hardiness, edibility, potential poisons, and other uses (you can tell this was filmed in the 90's when he mentions how 'big' a disk you needed to store the database). The last was on the subject of some applied urban permaculture with Mike & Julia Guerra.

Saturday 25 February 2012

Replacing Small Parts by Rapid-Prototyping

Since getting back to the city I've been on a small spree of trying to find little things that I could replace or redesign using 3D printing, whenever there was a moment to spare.

Firstly, for a long time I'd been meaning to make replacement parts for a very humble purpose, the male buckle clips on a couple of Highlander rucksacks I have that had mostly lost their teeth after many years of fatigue when packing and unpacking heavy luggage, while the rest of the nylon construction remains as functional as the day I got it.
The buckles used here, with 'Rock Lockster' imprinted along the T-shaped guide, lasted for probably a few thousand clip-unclip cycles over the course of several years before teeth started to break off all the clips. The replacement I made is shown clipped in.

Tuesday 7 February 2012

Digging A Small Swale

Towards the end of last week I posed an open question to the awesome folks on the open-source social network Diaspora*, asking if anyone could think of a good way to visualise the relationships of beneficial/detrimental interactions between various plants. If we can figure that out, it might make my job of deciding how to arrange the smaller shrubby plants a lot easier, and similarly make it easier for anyone in future.
While I got a friendly response but didn't get any answers to the question itself that night, I updated my map in more detail, noting a few places where I thought various crops ought to be planted just as a draft, using freely-available information on companion planting available online, such as Wikipedia's List of Companion Plants, which unlike some of the other lists, is more likely to evolve over time.
Extra zoomed section on the left has a key along its left border.

Thursday 2 February 2012

Taking Cuttings

When you're trying to establish a stand of trees or bushes (or planting anything that germinates slowly, for that matter), a far cheaper and faster option than buying plants in can be to take cuttings off some overgrown branches of a friend's plants with their permission, and get them to root and form new plants.Ideally, when taking cuttings you should try to start the end that you want to root around one of the points at which the parent plant branches, and trim the smaller branch of your cutting back to that point, as for botanical reasons that I haven't bothered to research yet, the cells around such a node seem to find it easier to change their growth pattern into a root. You can also improve your chances by treating the tip that you want to root with a solution of 'rooting hormone', usually particular synthetic auxins that instruct the cells there to grow root structures.

In my case, to create a fast windbreak hedgerow, I have a couple of brilliant plants available for the job, where my friend and their neighbour have willow trees and blackberry brambles, which grow so vigorously that you can often just shove a stick in the ground and it will root. In fact, the former is so good at spreading by this method that it is considered an invasive weed in Australia, and my friend tells me that one time they tried to make a fencepost out of a freshly cut beam of willow, it grew into another tree where it was placed.

Monday 30 January 2012

Permaculture Design

Recently a friend has given me a great opportunity to try out a new design science, Permaculture, by developing a self-sustainable miniature food forest on an allotment in the Scottish Highlands. Studying permaculture design and getting ready to move out of the city over the next couple of months, has of course meant that I haven't had much time to do 3D design and writing recently, however moving soon also means I will eventually have more time and opportunity to test out my own wind turbine designs and other tech.

Having watched several hours of a wide variety of instructional videos and documentaries on various aspects of permaculture that can be found in many places online such as youtube, plus starting to read the first few chapters of Bill Mollison's brilliant "Permaculture: A Designer's Manual", I had enough grasp of the basics to start hashing out my first ideas and designs, and learn more as I go along by testing. My approach could be seen as 'jumping in the deep end', and while I would like to spend more time learning before acting, possibly even take a course on the subject, a constraint of time means that if I don't start implementing at least a few changes to this land immediately, then I'd miss the important winter period when trees can be easily moved bare-rooted and planted, while a constraint of money means that I wouldn't be able to afford attendance fees at most courses anyway.
Nonetheless, I agree somewhat with Mollison's thoughts in his manual that "Starting with a nucleus and expanding outwards is the most successful, morale-building and easily-achieved way to proceed." Where he and many others have advised that you can learn much by simply sitting back and observing nature, then testing any hypothesis of its workings, I hope that I can use nature as my university, as the ones with walls don't seem very conducive to learning.