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Useful Kiln Tools + Beeper Upgrade

Kiln Beeper I installed a mini beeper in my kiln and adjusted the software to beep letters in Morse code depending on the stage of the program. I just used the same transistor+resistor+5v supply design as for the SSD control line to prevent damage to the pi. Kiln Tools Roll of cake making acetate: useContinue reading “Useful Kiln Tools + Beeper Upgrade”

Identifying a thermocouple

Next up in the riveting Thermocouple series is how to identify an unknown thermocouple as a Type K. There are loads of videos on Youtube on this, but I didn’t find them completely conclusive. Many of them advise “checking the colours of the leads”. Surprise! There are at least six different standards for colour codingContinue reading “Identifying a thermocouple”

The Perils of cheap Ebay stuff, or, why doesn’t my MAX31855 thermocouple board work?

I’ve been playing around with Type K thermocouples for a project. These are cheap, commonly available, and can read a temperature range from –270C to 1260C (though it depends on the exact thermocouple). It looks similar to this (you stick the metal pointy end in the hot thing): The above is a Type K thermocouple,Continue reading “The Perils of cheap Ebay stuff, or, why doesn’t my MAX31855 thermocouple board work?”

What’s eating my Cotyledon Orbiculata?

It’s not been looking well for a while, poor thing….. Then I spotted the underside of the leaves were covered in little black things…. to the microscope! Aphids! Bastards! Well, getting rid of them is relatively easy: blasting it in the shower removes them. I could try some isopropyl alcohol, but I’m worried it’ll harmContinue reading “What’s eating my Cotyledon Orbiculata?”

Moles, Avogadro’s Number, and Atomic Mass Units

I quite enjoyed Chemistry in Secondary School: I think I even did a CSYS course in it. However, I remember always having problems with the concept of a Mole and the calculations surrounding it. I’m not sure if I was being particularly dim, or just didn’t have enough context be able to relate to itContinue reading “Moles, Avogadro’s Number, and Atomic Mass Units”

Turn it Off and On Again

I’ve been doing a lot of interesting projects recently, so I decided to restart my blog. I wanted to keep the old articles, mainly for my own interest: However, I think things like the etched brass domino mask I made are still pretty cool. I decided to use WordPress.com, which meant I had to rescueContinue reading “Turn it Off and On Again”

Interactive fiction

Great! Finally found a decent IF interpreter for android: text fiction Now playing Anchorhead on my tablet. Really liking the SMS style interface, and it works really well with the android slidy keyboard.

Mobile development on Android and iOS

I’ve been doing a spot of iOS and android development for some sample apps today, which I’ve not done for a while. TL/DR: Yuck, ObjectiveC is a horrible blast from the past. Yuck, Java is a horrible blast from the past. About even then 🙂

MongoDb optimisation for scale

I redesigned the schema for one of our MongoDb clusters today. In doing so, I managed to reduce request times by 1.5 orders of magnitude! We’re now sustaining request times of roughly 30ms. The first mongo schema was about 400ms on average, with occasional bursts to over a second. 30ms is also much better thanContinue reading “MongoDb optimisation for scale”

PHP MongoDb replicaset gotcha

Ran into a gotcha with PHP+MongoDb the other day. Now, PHP ain't my favourite language, but its what Piwik is written in so I'm stuck with it for that. I've partially ported Piwik to use mongodb (vs mysql) as a storage system for scalability reasons. The problem is that if you're connecting to a mongodbContinue reading “PHP MongoDb replicaset gotcha”