HackSpace_-_April_2020

LENS

it has a tendency to slowly leak through or
melt most bottles. I still wasn’t happy with
the result and gave up on vapour smoothing
entirely for this project. My experiments
weren’t a waste of time because I learned
a lot, including that this particular solvent
was useful for gluing parts together by
melting them slightly – a technique called
‘solvent welding’.
I settled on old-fashioned wet sanding to
be the best approach. Nobody likes sanding,
but it worked well here, using increasingly
fine grits to polish it and then coating the
surface with matt varnish.

SOFTWARE
The council publishes which bins are due for
collection on its website, but the page was
designed for people, not software, to read.
If you view source on most webpages, you

will see it is a sea of hard-to-read HTML –

writing code to deal with this is challenging.

Luckily this problem has already been solved

using a technique called ‘screen scraping’

which allows a

computer to read

information usually

designed for humans to

read. Using a screen-

scraping library will filter

out unneeded data and

let you extract just the

bit you want.

Despite the ESP8266

being a fairly fast

microcontroller, it

would still struggle

under the pressure

of downloading and

parsing large

Left

A collection

of hazardous

chemicals

Below

Sanding the

indicator smooth

I tried vapour smoothing to remove layer

lines, a technique normally used with ABS,

but not so much with PLA