Thursday, 23 May 2013

3D Printing

I've always planned to blog about my experiments with 3D-printing, since I began building a Reprap 3D-printer last year. I don't know how regular bloggers manage to find the time.

I recently gave a talk on 3D-printing to the Hacker News Meetup group. It was a much bigger event than I'd anticipated, but on the plus-side the talk was recorded : Here's a link to the Vimeo page.

I should also put in a plug here for the Meetup group that I organise : Future Manufacturing

Thursday, 5 July 2012

Green Roof in Flower

I've been really surprised by this roof. I expected sedums to be green and quite boring, but the various sedum varieties have been blinding us with colour for over a month.

There's such a wide variety in their basic form, even when they're just green, but this really comes out when they flower. The yellow star-shaped flowers are just starting to fade, but the clustered pink flowers on their red stalks are taking over.

If you look at a Google Earth view of this area, it's one of the least green parts of London. Hence, it's quite poor in biodiversity. So I'm really happy to see the green roof crawling with bumblebees like this guy...

Finally, here's a close-up showing some of the colours and textures of the different sedum varieties.

Saturday, 12 May 2012

Micro-Allotment : First Harvest

In the 5 years or so since we've lived on the barge, we've grown flowering plants and some vegetables/herbs in pots. This year we decided to step it up a little by creating a micro-allotment on the main cabin roof.

I started by building a couple of beds out of some plywood left over from refitting the interior of the boat. These are both 4' x 2' x 1' to get the most out of the 8' x 4' ply sheets.

They're filled with compost from the Local Authority Recycling Centre nearby, over a layer of worm compost from our wormery which sits on the front deck near the anchor winch.

To the right of this picture is the sedum that we had left over from the green roof.

Jarvis the cat has been very helpful - he hasn't dug up the seedlings, and hasn't used the beds as a giant litter tray.

We quickly filled these plywood beds with onion sets and short rows of seeds : carrots, radishes, spring onions, beetroot (yuk), and rocket.


 So we combined with a group of our neighbours and bought some fabric 'grow-beds' from Marshalls. There are now around 15 of these beds dotted around the marina, and we joined the Mayor's Capital Growth scheme as 'Poplar Dock Micro-Allotments'.

This bed contains strawberries, mange-tout peas, lettuce varieties and a few cauliflowers grown from seed. The idea is to catch-crop and make the best use of the limited space.

Despite the wet, cold and quite gloomy weather, the seeds in trays are growing faster than we can plant them out. We're giving away seedlings to anyone passing (whether they want them or not!!) - luckily, we're not the only boaters here who are desperate to garden, and to show that it's possible to grow food with NO land whatsoever.

 I'll be blogging more about the micro-allotment as the Summer progresses. Also, Herself has seeded one of the fabric beds purely with bee-friendly wildflowers, and this will probably warrant an entry of its own. (If only we could keep a beehive too...)

Thursday, 10 May 2012

Green Roof on a Barge in Docklands

I've been wanting to build a green roof ever since I did a RESET course with Dusty Gedge and Gary Grant of Living Roofs a couple of years ago. However, when you look at the websites of suppliers and they're showing pictures of massive corporate roofs of several acres, my little order for 4 square metres didn't seem big enough to warrant anyone's interest.

Also, we wanted a wildflower meadow - a type of green roof which ordinarily needs a thick layer of substrate. This would have simply looked wrong, aesthetically, and would have spoiled the gracious lines of the boat (which, incidentally, is a Motorschipp built in Amsterdam in 1924).

Luckily, Wallbarn didn't make me feel inadequate when I phoned to enquire about small quantities of the materials I'd need to build a roof on the stern cabin of our Dutch barge. In addition, they offered an intriguing solution to our 'wildflower meadow' wish - they could supply sedum matting in a thin layer, but with a specialist London Wildflower mix seeded into the nursery-grown sedum. It will be hit-or-miss as to which of these species find a foothold in amongst the sedums, but that makes it all the more interesting and experimental.

Construction :

Steel boats are ideally suited to having green roofs. The deck is designed for the point-loads imposed by people and equipment, and so is structurally well capable of supporting the distributed load of a wet green roof.

The roof materials arrived on a pallet : a 20mm drainage layer, geotextiles, bagged substrate, and rolls of sedum matting grown on a coir-fibre mesh. It was important to unroll the sedum as soon as possible.

The roof itself had already been prepared by ensuring that all the paintwork was in good order, using Jotun marine-grade paints from Shepherd Marine and Vactan to stabilise any rust patches.

The roof was edged in bamboo supplied in 1m rolls, cut from their original 150mm down to 75mm to keep the profile low.

The green roof is built up with a series of layers to control drainage. In this case, a geotextile mat was first used to cushion the underlying roof, then a dimpled drainage layer (20mm dimples) is used to collect infiltrated rainwater and to supply water to the vegetation. This is covered with a second layer of geotextile to retain the substrate, a 40mm layer of crushed brick material with low organic content.

At the lowest point of the roof, a drainage channel of cobblestones allows excess rain to drain away.

This picture shows the various layers meeting at the drainage channel - the detailing allows water into the channel, but retains the crushed substrate.

Once the substrate had been levelled out and lightly tamped with a block of wood, it was a fairly simple matter to roll out the sedum blankets, cut them to the shape of the roof with a sharp knife, and then water the roof liberally (in this case, the heavy rain showers that interrupted the whole build did the watering for us...

Then it was a case of sitting back to watch it grow and to wait for the wildflower seeds to begin pushing through.

Benefits of Green Roofs :

Apart from the obvious aesthetic qualities, green roofs have several major benefits, whether they're on a barge or a building. The most important factor, especially in the highly developed urban area in which we live, is the ability of vegetation (and soil) to remove air pollution. In addition, they're a major component of SUDS (Sustainable Urban Drainage Systems), slowly releasing rainfall to stormwater drains and so avoiding Combined Sewer Overflows (CSO's). (This isn't a major concern on a boat, surrounded by water...)

They're also beneficial in the thermal performance of buildings, providing an additional insulation layer which prevents both heat losses in winter and also heat gains in summer. Moreover, the evapotranspirative and albedo effects of growing vegetation both serve to cool the surrounding air, reducing the Urban Heat Island Effect (UHIE). 

The important biodiversity potential of this roof will depend mostly on how many of the wildflower species take root in the sedum matting.

Other quantified benefits of green infrastructure components include health and well-being, and even reductions in crime.

My MSc Dissertation went into a lot more depth on these issues, and I'd be happy to email a copy of a conference paper that I presented on this subject if anyone out there reads this and wants to know more. Just DM me via Twitter.

Wildflower Seed Mix :

It's unlikely that all the different species seeded into the sedum will survive. I'll be following how they do, and keeping an eye on what insect species are drawn to them. The species supplied were as follows :

  • Agrimonia eupatoria, Agrimony
  • Anthyllis vulneraria, Kidney Vetch.
  • Centaurea nigra, Common Knapweed
  • Clinopodium vulgare, Wild basil
  • Echium vulgare, Viper’s Bugloss
  • Galium verum, Lady’s Bedstraw
  • Hypericum perforatum, Perforate St John’s Wort
  • Knautia arvensis, Field Scabious
  • Leontodon hispidus, Rough Hawkbit
  • Leucanthemum vulgare, Oxeye Daisy
  • Linaria vulgaris, Common Toadflax
  • Lotus corniculatus, Birdsfoot Trefoil
  • Malva moschata, Musk Mallow
  • Origanum vulgare, Wild Marjoram
  • Plantago media, Hoary Plantain
  • Primula veris, Cowslip
  • Prunella vulgaris, Selfheal
  • Ranunculus acris, Meadow Buttercup
  • Ranunculus bulbosus, Bulbous Buttercup
  • Reseda lutea, Wild mignonette
  • Sanguisorba minor ssp. Minor, Salad Burnet
  • Silene Vulgaris, Bladder Campion

I'll be blogging more about this green roof in future, as the roof beds in and as these wildflowers emerge. I'll be talking more about green infrastructure too.

Wednesday, 16 November 2011

Revolting Students

If a foreign country took this approach to its students' rights to peacefully protest, we would probably invade them, in the name of 'Democracy' - at least, we'd check whether they had oil, or whether we'd sold them any armaments recently.

The Metropolitan Police issued warnings about plastic bullets and water cannon, and the right-wing press lapped it up - if you don't have a strong argument against it, well you can intimidate it out of appearing, or kettle it when it does.

I turned up to witness. I met a number of people like me - pretty normal middle-aged people who celebrate the students' right to protest about their own future, and who were there to make sure that no liberties were taken - literally.

The students are angry about rich people who themselves benefitted from University grants making decisions to charge £9000 per year tuition. They're angry about 4000 Police Officers being provided to protect the Corporation of London - a secretive state within a state which makes the Vatican look honest - from a peaceful protest of a couple of thousand students.

Where were these Police resources when Tottenham was burning, and Hackney, and Clapham ?

The students' arguments are inextricably linked to the Occupy protestors at St. Pauls Cathedral, who argue for higher taxes for the bankers who profit and get bonuses for destroying economies, businesses and livelihoods; for tax-evading corporations to be prevented from off-shoring billions in taxable profits.

 Those Officers I spoke to were perfectly decent and helpful to me - they were simply doing a job and doing it well - so this is not an anti-Police rant. But I just wonder whether these Police Officers who protect that corporate machine will be able to send their own children to University, or get them a life-saving NHS operation if they're unfortunate enough to need it.

Tuesday, 15 November 2011

My Letter to Boris

Dear Mayor Johnson
The BBC today reported that Transport for London will now "look closely" at Bow Interchange in relation to cycling. It will also direct cyclists away from the junction during the Olympics next year. This is not a plan.

Even when your organisation is finally prodded into action by the sickening deaths of two cyclists in such a short period of time, the proposals are "too little, too late" in the extreme.

Your comments last week were insensitive and dismissive. I expect leadership from the Mayor of London, and, despite your obvious support for cycling, you are fast losing the support of London cyclists and potential cyclists - despite, I suggest, no increase in support from drivers, and certainly no decrease in air pollution levels.

Your policies are increasing the take-up of cycling, but how long before the first Hire Bike death is reported ? And the second ? And the first BorisBike death on a Cycling Superhighway ?  You really must follow through on the policies that you have initiated - CS3 is largely separated from roads and gets a 9/10 - but then the more recent CS2 would be a joke in blue paint, if it were not that it is killing and injuring people.

Yours sincerely
Mark (surname withheld from Blog)
London E14

Tuesday, 8 November 2011

Red Light Jumpers sans Helmets

OK, why is this ? Here's the heart-rending story of a widow, Pamela Smith, grieving the needless loss of her husband when he was killed by a cement lorry in Fulham. As the story outlines, Paul Joseph, 45, pleaded guilty to causing death by dangerous driving. It's serious - life and death serious. You might expect serious consequences for someone who admits that his decisions and actions killed someone.

And yet : "At Southward [sic] crown court he was sentenced to 16 weeks' jail, suspended for two years, and ordered to carry out 120 hours of community service." There's no mention of whether he lost his driving licence - maybe he's still out there driving, doing his 'bird' in his spare time. He goes home to all the comforts, while Pamela Smith and her 3 children have had their life pulled out from under them.

Now that's enough to make any sensible person angry. If today's newspaper is tomorrow's chip wrapper, then I don't know what that says about yesterday's comments section. So I'm copying my own immediate reaction to the story :

"Can anyone be surprised that drivers are more aggressive, careless and selfish, and that cycling KSI's in London are increasing alarmingly? The Police do not enforce basic Highway Code rules against bad driving, and the courts let these deaths slide by as 'just one of those things...' This is one more case of drivers being given a presumptive 'license to kill.'

The Barclays Cycling Superhighways are bringing their sponsor into disrepute, and TfL are facing corporate manslaughter charges over Bow and King's X. But the only action we see is reducing pedestrian times on crossings and intimidating peds and cyclists off the roads - all in the name of Boris's election mantra - traffic flow - a sop to the outer boroughs.

If I, as an architect, designed a building programme and then the contractor pushed workers to flout H&S measures, then under CDM (Construction Design & Management) laws I could still be charged with Corporate Manslaughter - it's time we started looking at the hours worked, scheduling and pressure to perform that the haulage firms put on their drivers. If the haulage firms are too cheap to install cameras and decent mirrors, they should be excluded from public contracts, or barred from entering Central London.

Until the Mayor and TfL, the Police and Courts begin to take this seriously, deaths of cyclists and pedestrians will continue to be 'acceptable losses' - Everton Smith, Eilidh Cairns, Deep Lee and Brian Dorling were people, not statistics."

 Soon after my post, someone calling himself "Clarkson for PM, England - but sometimes it doesn't feel like it" chipped in. I can't repeat what he said because at some point his comment was removed - I hope he (and I'm sure it was a he, not a she) removed it in utter shame. Rather than empathising with Mrs. Smith, or even acknowledging any part of the story, his response was along the lines of "2 wheels bad, 4 wheels good, get a car." I paraphrase (and I'm being kind to him).

A little later, Davey_Buoy, Chertsey popped up and asked, "When will people understand that it has taken many years just to get the roads set up for Cars Lorries and Buses,two wheeled Bikes dodging in and out of this traffic is not really feasible,whether you have a silly plastic hat on or not."

Again, he ignores the story, of a middle-aged man cycling home from work, not (as far as we're told) jumping lights or being in any way the cause of this tragedy. Again, blame the cyclists.

 To this I responded, "Drop the patronising tone. Other European capitals manage a safer balance between vehicles, cycles and pedestrians - and maintain a better urban quality of life.
TfL and corporate influence have ensured that people are expendable for the sake of a few seconds saved in getting to the next bottleneck junction. If the roads are 'set up for' cars/lorries, you imply that the existing situation is acceptable - but it doesn't work for anyone - not cars, lorries, buses or cyclists.
On top of the road deaths, there's also the 4000 air pollution deaths in London each year - it's time for some leadership here, not pandering to the selfish interests of bullies.
Why do you people bring every conversation about cycling safety back to red lights and bike helmets, and ignore the attitude (fuelled by a not-fit-for-purpose infrastructure) of drivers?"

It seems that every time there's a story in a newspaper about cycling, a bunch of idiots quickly slither out from under rocks, ignore the story, and troll the comments section with inane (and often offensive) comments along the lines of "cyclists jump red lights....  Cyclists don't wear helmets.... Cyclists don't pay 'Road Tax'..."  This is their justification for aggressive, bullying or murderous driving.

So what I'm wanting to know is how this almost Pavlovian reaction crops up so often. Is it the Clarkson factor ? Is it some deep-seated anxiety coupled with a small penis ? (But then, there are occasional women who post the same inane crap... penis-envy?)  I'm no psychologist, but it seems to me that these reactions, and a lot of the bad driving that we see day after day,  are the very definition of psychopathic.  Here's the Wikipedia definition : "Psychopathy is a mental disorder characterized primarily by a lack of empathy and remorse, shallow emotions, egocentricity, and deceptiveness. Psychopaths are highly prone to antisocial behavior and abusive treatment of others, and are very disproportionately responsible for violent crime. Though lacking empathy and emotional depth, they often manage to pass themselves off as average individuals by feigning emotions and lying about their pasts."

This story came out on the day following the news that there will be no new inquest into the death of Eilidh Cairns. Eilidh was run over by a lorry in Notting Hill in 2009, and a coroner recorded a verdict of accidental death. The driver, Joao Lopes was fined £200 and received 3 points on his licence because he had defective vision. It has been reported recently that this same driver struck and killed 97-year old Nora Gutmann. "Three months after the fatal incident in Notting Hill in February 2009, Lopes had failed an eye test and his driving licence was revoked. He got it back in April 2010, and returned to driving HGVs."

Now I'm starting to wonder not only about the mental health of these Clarkson trolls who infect the comments sections. I'm looking at the Justice system, and I'm looking at Boris, and I'm looking at the remote and shameless TfL bureaucrats, and I'm looking again at that Wikipedia definition of psychopathy.