Tuesday, December 21, 2021

An elder writes

I have very much enjoyed David Suzuki's book The Legacy - ISBN 978 1 74237 355 3.
It describes the importance of the environment and how close we are to catastrophe. I calls on us to act.

Sunday, November 7, 2021

Measure the air you breathe

A simple cheap device is available to measure air quality - 
A) CO2 = Carbon dioxide, fresh air is 350 to 450 ppm.
1000 to 2000 ppm indicates poor air quality and causes drowsiness.
Current measurement at Hawai'i is 414 ppm.

B) HCHO = Formaldehyde, maximum recommended exposure is 0.100 mg/m3

C) TVOC = Total volatile organic compounds, maximum recommended is 0.250 mg/m3

D) Temperature 

E) Humidity

You can see that inside my home the air quality is as good as the outdoor air.

Friday, November 5, 2021

In the club

The Lead Pencil have responded to my request for membership with a yes.

Sunday, June 27, 2021

A pencil of one's own

The symbol of the Lead Pencil Club is a yellow Number 2 pencil with the text NOT SO FAST.
I have learned that American Number 2 is equivalent to Australian HB. The Australian ( in reality British ) system is that pencils with soft dark graphite are called Black - B. The more black are modified with a number - 2B, 4B, 6B, etc. Pencils with hard graphite are designated H, these make a fainter line. They are also graded with harder - and fainter pencils modified with a number - 2H, 4H, etc.

HB pencils are supposedly the happy medium between H and B. They are the most popular grade. You can buy they in packs of a hundred.

In 1971 - in primary school - I had moved to a new grade and - disgarding my slate - I was using HB pencil and paper. The teacher disgusted at the grubby marks on my writing pads called my mother in and said that I was to use 4H pencils. This would prevent me smearing graphite over the page. I did all my school right through to university with 4H pencils.

Recently re-looking at pencils - in my attempt to not use plastic biros - I find that I prefer 4B sharpered to a fine point. This gives a dark legible line.

Friday, June 25, 2021

The Lead Pencil Club

The Minutes of the Lead Pencil Club edited by Bill Henderson ( 1996, ISBN 0-916366-84-7 ) is a great read from the beginning of the internet. Some of the contributions are prophetic - I thought M. Kadi (page 175) was particularly accurate. 

Wednesday, June 23, 2021

Sweet Heinrich

The sugar shaker is 1950s German technology - it dispenses sugar without using possibly contaminated teaspoons. It is making a comeback in a covid world. As a bonus it has no moving parts to wear out and can be constructed without plastic.

Tuesday, June 22, 2021

Custom Clamp


The improved jockey wheel at the front of the camper trailer came with a clamp that allowed for a load up to 400kg and had 4 different clamping heights.
Great! Except that the clamp only suited a 75mm bar. I asked a local engineering firm to attach a backing plate for a 100mm bar and it all works very well.

Gas Lighting

Gas lighting was nominated as word of the year yesterday by Mirrium-Webster. When I look it up, the source of the term is nomin...