Tuesday, 11 October 2016

Standing desk attachment

The desks we have in the office at work are a weird height. Until recently the desks were also incredibly wobbly as they are all joined together along a wall, and they were only attached at the back of the wall. There were no supports at the front of the desks. A few years use by PhD students and post-docs and several computers had weakened the support in the back making the desk slope and be wobbly.

But a few weeks ago we got extra legs put in in the front of the desks. This meant no more wobbling or sloping desks! Since the desks were now stable some of us in the office tried some DIY standing desks.
Plastic box as a standing desk
Just this upside down plastic box worked pretty well to relieve some back strain once or twice a day, but it was annoying that my mouse couldn't fit on there as well. I googled a bit on making a standing desk attachment, but didn't really find any satisfactory designs. So I decided on making my own.

To settle on dimensions I measured the height of the plastic box - around 280 mm. I decided to make my piece 290 mm as it would be easier to make it lower than higher should I wish to change the height. For the depth I measured the depth of my keyboard, added some length and rounded it up to 300 mm. For the width I decided it had to be 600 mm or more. I found a huge mouse pad cheaply on AliExpress with the measurements 300*800 mm. The space under my desk was 850 mm wide, so something 800 mm wide should fit under there if I needed to store it away. And again, easier to make it smaller if necessary than make it larger.

After drawing up a few designs on paper and looking through the materials pile in the workshop, I settled on a plywood top with a frame all around the bottom and wide legs that would screw into the frame. All the wood was leftovers from my father-in-law making a new deck for his pick-up truck.

Tools used:  tape measure, caliper, pen, square, wooden pallet to clamp things to for cutting, 2 speed clamps, circular saw, vice, belt sander, vet-and-dry vacuum cleaner, Power drill*2, impact driver, 3 mm drill bit, square bit, countersinker, wooden stick to stir paint, paint brush

Materials used: Plywood sheet, wood (similar to batten), square head countersink screws, light gray acrylic paint, magazines for paint protection

First I marked and cut the plywood to size.
Scrap plywood piece with drawing on top
Since the desk space in our workshop is filled with lots of things, and the workshop has carpeted floor we try to not do dirty jobs in there, but keep it in the garage or outdoors. I used pallet we had laying around and clamped my wood pieces to it with speed clamps. A battery powered circular saw was used to cut all the wood.
Cutting the plywood.
Then I cut the framing and made sure the pieces were the correct length.
Checking that framing is cut to right length
Finally I cut the legs out of the same wood as the framing. Ideally I would have liked slimmer legs, or possibly metal legs - but this way it was free and easily available.
All pieces together. The stack is the 4 legs.
The framing pieces and legs were quite rough as they were offcuts from a much larger piece of wood (actually they are offcuts from the wooden sides of the pickup truck tray where the vice is fastened). I held all the pieces individually in the vice, clamping them with wooden pieces to avoid making vice marks in the soft wood. I used a belt sander with 120 grit sand paper and a wet-and-dry vacuum cleaner attached to the sander to get rid of most of the sanding dust.
Sanding the framing and legs.
After sanding all the pieces I did a quick test assembly. I used speed clamps to hold the framing pieces to the plywood and I pre-drilled all the holes. I didn't bother countersinking the holes at this point. The legs were then pre-drilled, countersunk and screwed on.
Clamping the pieces in the right spot for drilling and screwing. 
Finally the first version of the standing desk attachment was done. I brought it into the home office and did a quick test - making sure the piece wasn't lopsided and that it would fit a standard size keyboard and mouse comfortably.
Quick test to make sure it wasn't lopsided.
Once I knew that the piece wasn't lopsided I added some more screws, pre-drilling and countersinking the holes. I also unscrewed the first few screws to countersink the holes now. This step was very fast thanks to having two power drills and an impact driver. After adding more screws to the legs to stop the slight wobble the piece became slightly lopsided, so I had to sand the bottom of the legs a bit. After some work the piece was standing properly again.
Adding more screw, countersinking holes.
After this step I brought the piece in to work to test it for a week, making sure the height was suitable and that the size was good. I brought it home again the following weekend to add a few more screws, sand it some more and give it a few coats of paint. We managed to find a bucket of light gray acrylic paint in the clearance shelf of Mitre10. The colour goes really well with the desk colour.
First coat of paint.
After 2-3 coats of paint I brought it into work. I added some silicon non-slip stick-on circles under the legs to keep it from sliding around on the desk. I used it for about one week like this before the large mouse pad arrived. Before I had to use a piece of paper as a mouse pad as the surface wasn't smooth enough for the mouse to work properly and I couldn't find any spare mouse pads.
Finished piece.
Then the mouse pad arrived and the standing desk attachment looks really good and works perfectly.
Standing desk with mouse pad.
Total work time for this project was probably around 6 hours.

Friday, 2 September 2016

Super insulating curtains

After moving to New Zealand I learnt that curtains have other uses than being purely decorative. They are used to keep the room warm. This might seem trivial, but in Sweden curtains are almost purely intended to make the window prettier.

In New Zealand houses are pretty badly insulated and the windows are only single glazing. This is of course not true for all houses, but for the majority. Especially if you are renting. We are renting a fairly well insulted house by NZ standards but it is still freezing on a cold day.

Patrick had the great idea of using bubble wrap as an insulation material. I decided to try making curtains using bubble wrap for our bedroom.

We bought some thermal curtain fabric from Spotlight. We did some tests with a cellphone camera flashlight behind the various fabrics to find one that would be reasonably sun blocking as well to allow us to sleep in without being woken up by the sunlight. We also bought some extra strong thread in a matching colour to the curtain fabric as well as some curtain loop tape and some curtain loops. I also had to buy some pins as this was my first sewing project since moving to NZ.

I cut the fabric to size and folded in the sides and top curtain edge, pinned and hemmed them. Then I sewed the curtain tape onto the curtain (after figuring out how curtain tape worked). I cut strips of the 50 cm wide bubble wrap from the 100 meter roll I purchased from Packaging House in Petone. I put down one layer of bubble wrap with the flat side towards the curtain. Then I put down a second layer - offset horizontally from the first - with the bubbles facing the other bubbles. The bubbles stick fairly well to each other, and the bubble-bubble interface gives even more insulating air pockets in the middle layer of the curtain.

Then I put the top edge of all the bubble wrap between the curtain tape and curtain fabric and pinned it down. I bent a number of pins doing this. Then I set the sewing machine to the longest straight stitch it could do. Sewing through bubble wrap makes exciting sounds. Since bubble wrap is a thin plastic layer it is a good idea to have fabric on both sides of the bubble wrap as you sew it. Having fabric on one side and curtain tape on one side worked very well.
I now had two stitched lines on the top of my curtain, and I used the curtain hooks between my sewed lines to hang the curtain.

The curtains work like a charm! Our bedroom is enormously warmer than last year, and even during really cold nights it is enough for us to keep our little thermostat oil fin heater on setting 1 out of 6, and it doesn't turn on very often to heat during the night.

For next time I would suggest:
- Use wider bubble wrap. My plan was that the 50 cm bubble wrap panels would make it easier to pull the curtains away from the windows, but after making them I feel that using a wider wrap wouldn't have done much difference in that respect. The slim panels do however tangle a bit when hanging and moving the curtains. I would suggest using at least 1 meter wide bubble wrap.

- Use a backing fabric as well. We have noticed a weird plastic smell from the bubble wrap when it heats up from the sunlight hitting our window. It is a fairly unpleasant smell. After putting another layer of fabric between the bubble wrap and the window the burnt plastic smell is basically gone. I used another layer of thermal curtain fabric, but white. Both to minimise the energy absorbed by the outer layer to minimise the burnt plastic smell, and because it was the cheapest thermal lining. I think any white fabric would have done the job, but this way I don't have to worry about moisture leaking through the white fabric either.

Friday, 10 June 2016

Python and programming

When I started my Master's degree in 2014 I knew how to program in MATLAB. My supervisor suggested that I learnt OriginLab to process my data and make pretty graphs so I did. It took me several weeks to get the IT department to find who had the license keys to the university's distribution of OriginLab.
And after spending a year using OriginLab on a university PC (very slow machine) and being enormously frustrated at it eating all the RAM of the computer I decided to stop using proprietary softwares for my data handling. That meant scrapping MATLAB as well.

I had taken a half-day workshop in Python and knew that it was fairly similar to MATLAB in the basic data handling and plotting functionality. So after finishing my Master's degree I was waiting for my visa for going back to New Zealand for my PhD and decided to take a 10 week online course at edX from MITx in computer science using python. It was really good and I learnt to handle python pretty well. I've also heard great things about Codecademy from fellow PhD students.

I have since been doing all of my programming in python and I am very happy with my decision to learn it. I no longer have to worry about licenses or compatibility between operating systems.

Up until now I have mainly used Spyder for my python programming. It is a great way to convert from MATLAB to python, as it is built basically the same way. It also comes with almost all packages pre-installed and it is pretty much plug-and-play. If you are not used to using the terminal Spyder is a great choice. This week at a workshop run by MESA I was introduced to Atom and running scripts from the terminal. I think Atom is a much better code editor than the Spyder editor so I will be migrating over to Atom over the coming weeks. I will also take to opportunity to rewrite all of my scripts from python 2 to python 3. No major changes required, but it should be done.

If you are considering changing from programming in MATLAB to python, I definitely recommend it. It has an enormous amount of packages, and many people develop machine communication protocols in python (very useful for automatic experiment monitoring). Python has a very active community. Every time I have encountered a problem it is usually solved within a few minutes by typing in the package name or error message into Google.

Saturday, 4 June 2016

Sewing machine

A few months ago I found what I had been looking for for a while: An old sewing machine!

On a trip the Souther landfill Second Treasures shop (second hand store) I found a great looking old sewing machine. The machine is a Pfaff Synchromatic 1209. It is made in West Germany, so it is pretty old. It is a very sturdy machine with a body mostly made of metal.

When I got it didn't sew particularly well, the threads kept making a mess. I found the original manual online and realised that the previous owner had not threaded the machine properly (and made extra notches for holding the thread instead). But even after threading the machine properly it kept making really ugly seams. So I got out a few screwdrivers and took apart the bobbin and soaked it in WD-40. I cleaned most of the insides with WD-40 too, and changed the needle (after finding a secret compartment on the side of the machine).

After letting the machine dry for a few weeks I put it all back together. I googled how to correctly set the bobbin thread tension and then gave it a try. And it ran beautifully! Below is a photo of the difference in seam quality before (left) and after (right) cleaning and re-tensioning. Notice the huge lumps of thread on the before picture? Haven't had a single incident like that since the cleaning.

Not bad for a $10 machine from the second hand store!

Friday, 15 April 2016

Transitioning to a blog

After two years of paying to have my website hosted I have decided to transition to using a blog instead as the cost of hosting my website is not proportional to how much use I am getting out of it.

I will miss tweaking settings in Wordpress for my own site, but I will still get to play with Wordpress in helping with the management of the MacDiarmid Emerging Scientists Association website and the Space & Science festival website.

Hopefully this blog will be more active than my website, and if not I am at least not spending too much money on it.