Wetsuits and cartridge heaters

Following the advice of Anonymous, I have bought a cartridge heater, found on ebay for under AU$8. It's 220VAC, 400W, which is more than I need, but not way too much, It will probably take at least a fortnight to arrive, and so I'm going to make the glue gun heater anyway, especially considering that I will need two heaters eventually anyway, as I brew in both a small 5L jar and a big 30L vat, sometimes simultaneously. Also, I have a small brew going at the moment, into which I would like to place a heater as soon as possible.

Insulation: I want thermal insulation for my vats, as I think I mentioned. I called up ACT foam and rubber and Clarke Rubber to ask after various foams for this purpose. I was quoted $39.90 p/sm for some stuff called 'form fit', which sounded quite good, or $120 for 2 square metres of neoprene. Being a cheapskate, I decided to find another source of neoprene for my insulating jackets. Wetsuits.

So, today on my way home from uni I stopped in at some op shops and picked up two absolutely hideous wetsuits, one for $15 and one for $20. The leg from one wetsuit provided me with an almost ready-made jacket for my 5L jar, and the trunk of the other, plus a strip from the trunk of the first, make up a jacket for the 30L vat.

I'll post some pictures soon.

Immersion heater plans and ideas

After struggling for a long time to find an immersion heating solution that was

a) affordable

b) relatively small

and

c) easy to immerse without contaminating the brew

I gave up and built a light box for my vat to sit on. This works well enough, but takes up space and has a light bulb in it, which is prone to breaking.

The other day, I was working on a vacuum box and needed to make a hole behind the electronics panel airtight. I did the obvious thing and filled the hole with hot glue. The problem being that my hot glue gun has a broken trigger mechanism, meaning that I have to manually push the glue sticks through. In the process of trying to quickly fill the hole up, I pushed ab it too hard, and shot the heating mechanism out the front end of the gun.

So no I'm down one glue gun. On the plus side, I got a small heating element that runs directly from mains power. Untouched, it measured about 10cm by about 2.5cm in height, and consisted of a stainless steel tube with the familiar conical nozzle at one end, with a stainless steel block mounted underneath, from which a pair of wires protruded. Guessing, based on the thickness of the walls on the stainless steel tube, that the heating element itself was confined to the block under the tube, I promptly cut the tube off to make the whole thing smaller. My guess was correct, so I now have a stainless steel heating element about 15mm diameter, 50mm long.

My next step will be to mount it in a brass or copper tube filled with mineral oil, this will allow me to mount it firmly throught the top of the vat, preventing it from touching the sides. It will also prevent the brew from conducting the 240 volts that are running to the element. There are two reasons for putting the mineral oil in there. Firstly, it is non-conductive, so the wires will be safe in there. Secondly, is removes air from the vessel, which is a poor conductor of heat, the oil will transfer the heat from the element to the brew more efficiently.

At the end, I hope to have a completely sealed unit about 200mm in length that I can easily mount, and easily swap between brewing vessels.

I'll post pictures and further information as I go.

Homebrew experiments.

As my previous post may imply, I've been playing around with homebrewing beer and with controlling the various processes involved in this. From now on, I plan to post my various prototypes, ideas, plans, and findings here. At the moment my list of things to integrate into my system includes:

-Improved thermostatic control, possibly using a PID system

-Immersion heater for direct heating of the brew, this also saves space

-Electronic hydrometer to tell me the specific gravity of the brew, the alcohol content, and when it is time to bottle

-A convenient, inexpensive, and space efficient method of thermally insulating the brewing vat.

I guess while I'm at it I'll also post the results and recipes of my more experimental brewing attempts.

Homebrew homebrewing thermostat

I've just finished my first protoype of my hombrew thermostat. Here is the schematic:

The source code is available at: http://arduino.cc/forum/index.php/topic,58725.0.html

The problem with the bike

I got an Avanti Blade 2 about July last year, and up until recently, have had no problems. Last Thursday night, however, I was about to ride to Civic for a night of alcohol-fueled fun, when I accidentally bent the rear wheel. I have to say, this was entirely my own fault, I won't go into details, but it wasn't a manufacturing issue. Anyway, it looked like a capital C, this wheel. Fuck, I thought, and found another way into Civic for the night (incidentally, my year 7 English teacher gave me a lift). The following day I took the wheel to the bike shop, where the man gave me a free emergency true (he hit the wheel on the ground until it was straightish). This wasn't enough though, the wheel wouldn't go round. I went back, and bought a new wheel for $110. He changed the gears and the tire over, I paid and left. That was where it should have ended.

On Monday, I cycled into the ANU for some pre-enrollment stuff; when I got there, just as I was about to pull up and get off my bike, the chain came off. No problems, I thought, I'll put it back on, and be on my merry way. WRONG. The chain had come off and become jammed between the gears and the spokes. This bent the spokes and, as a result, the wheel. It wouldn't go round any more. Caught halfway between a bike shop and my next destination, there was nothing for it but an emergency true (I hit the wheel against the ground for a bit).

In the end, I got to my next destination, with my bike. But I had to call in a lift home again, because the wheel re-bent a bit. So now, I have to take the new wheel to the bike shop, and give them yet more money. On the plus side, I've discovered the only (thus far) flaw in the bike, and I've Isolated a problem that was bound to get me one day anyway, but in an infinitely worse time and place, during a chase from angry drug-lords for instance.

The problem was with the derailleur; when I got the new wheel, I should have adjusted it a bit. Oh well, now I know, and have fixed it.

The flaw with the bike, which is irritating, but not fault-inducing, is the positioning of the brake-pads. The pads themselves are located between the rear forks and the wheel, nothing TOO unusual, but... there isn't enough clearance (room) to take the wheel out easily without deflating the tires; even after you've disconnected the brakes. This is incredibly annoying when you're trying to do an emergency true with no tools in the hot sun, as to check the wheel, you have to put it back into place, then remove it again frequently. This is SO FUCKING PAINFUL when you can't do it without applying most of your weight. On top of that, if, as I did, you have to disconnect the rear brakes in order to ride, you also have to twist them and pull them until they're on the other side of the frame, a very difficult thing to do, especially without tools.

Basically, the brakes need a redesign. Look out for Blade 3.