DIY Thermal Test Chamber (low budget)

This post is sort of a update on something 'quick and dirty' that I built for my day job. We needed to have a thermal chamber that we could flow gas through at an elevated temperature with the chamber holding samples of various materials. The cost of this project was to be kept to a minimum and there was no time during the work day to build it so I did it at home. Generally I don't like to work 'offline' on my own time but this seemed like a fun project so I built it. I'm putting this up online as reference only and I don't recommend that you build one unless you know what you are doing! (not to imply that I do).

 

There are a few things to consider after realizing that this isn't a big budget project:

  

• How to make a gas tight enclosed chamber that is thermally robust and chemically inert?
• How to heat that chamber to a predetermined temperature and keep it there?
• How can you see what is going on inside the chamber without opening it up and letting the gas out?

  

D.I.Y. Thermal Test Chamber

Fortunately we had several types and sizes of stainless steel Sanitary Fittings laying around and a temperature controller isn't that expensive (but it did consume the entire budget!). Sanitary Fittings are used mostly in the food industry as pipes to flow potable liquids (like milk, beer, water etc..) because they don't connect with threads and are easy to keep clean. They have flat flanged face seals that are held together with clamps so you can easily take them apart and clean them.

Windows Security and Privacy Update

I have finished the window covering that I wrote about last week - finally! They turned out pretty good and they do add to the security and privacy of the new house. This turned out to be a lot of work, I knew that going into the project but about half way through I was sick of it. Maybe sick is too strong of a word but painting and sanding is only fun for about 5 minutes, and only when you are watching someone else do it. Below are the before and after pictures:

 

Unsightly and Insecure Windows

Secure and Private Windows with Homemade Coverings

As I mentioned before these are just wood frames with bleached muslin stapled to the back. I think this looks a lot better than curtains and because the blinds are still there behind them they provide a lot of privacy. The bleached muslin allows light to come in and they are hinged so I can open them to peek out or clean the windows. Clean the windows?!? Yeah right! Click below to read a little more about how I made these - don't forget to click HERE too to see the start of this project!

Windows Security and Privacy

No this is not a post about the OS but about literally Windows Security and Privacy. The new place that I moved in to recently has really nice living room windows that look right out onto the street. They let a lot of light in and when the windows are open provide a nice cross ventilation for the entire downstairs. The one issue that I have with them is they are covered with really crappy old blinds. I wouldn't mind the blinds so much if it was a back yard on the other side of them but because it's a public street I don't like it. My feelings about this are probably influenced by the last place I lived, affectionately called The Cave, because there was no view, no windows and only a big steel security door between the downstairs and the street.

 

Bad Window Coverings

Above is a picture of the windows in the new place. Can you see what I mean? They look pretty bad and if someone wanted to see what was going on in the house at night they could look through all the little gaps.The last thing I need are pinhole camera shots of me in my skivvies eating potato chips on the couch ending up on the Internet without me getting any royalties! Anyway I live in a nice neighborhood but I can't help but feel like someone is looking at me all the time. Paranoia aside I decided that they need to be covered up if not only so I feel better but it's safer and more private. Click below to see my in-progress solution...

Free Energy and Bad Pot

I have more or less finished moving and unpacking everything and I decided to rest a bit and do something relaxing like fix a broken power supply! I decided to fix this not because I need the power supply right now, or because I found it in the garbage 2 days ago but because there is nothing better to motivate you to unpack as having the need to find something. For example: my soldering iron and digital volt meter. Both of which I had to use to fix the power supply and in the process of finding them I found other useful stuff too - like toenail clippers!

  

The power supply that I found is an Extech 382200 that has a 0-30 volt output and up to one amp. Both the voltage and the current are adjustable so this is a handy thing to have. When I plugged this thing in and turned it on the voltage display read 51.1 volts! That is a bit higher than the 30 volt rating and the voltage adjustment knob didn't do anything.

  

EXTECH Power Supply (broken)

At first I thought that the output transistors might be shorted so they were the first things that I checked. If the transistors short then the output usually goes higher than what it's supposed to be and it's not adjustable - of the fuse blows. The transistors are mounted to a big heatsink on the back of the power supply but to get at them I had to take the cover off. Check out the picture below!