The “Mr Redox” Home Energy Reactor (by alaric)

So, I work from home, which means I spend a lot of time in my workshop.

It's a long, thin, building. The door opens into the metalworking area; moving along the building, we get to the electronics bench, then to my desk. As I've previously mentioned, I want to redesign the place a bit, but I'll still be spending a lot of time in here. I have insulated the roof successfully, but the second front in my war against chilliness is my rocket mass heater.

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Electronics Projects (by alaric)

So, my electronics workbench is a mess.

This is abundantly clear in the picture from my blog post on redesigning my workspace; the awkward layout is certainly part of the problem, but a deeper problem is that I don't do many electronics projects. So this big workbench is rarely used for its intended purpose, and thus accumulates junk, and thus isn't very inviting to start projects at, which adds to the fact that I'm a bit edgy about STARTING electronics projects, and a vicious cycle has set in...

The only electronic projects I did lately were the 12 volt DC power distribution system for the van and a 9:1 impedance transformer, but those were mainly mechanical builds; the electronics were trivial.

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Insulating the Workshop Roof (by alaric)

I work from home, in my workshop at the end of the garden. I have my rocket mass heater to warm it in the winter, but while the radiant heat from the primary heat exchanger is comfortable, as soon as the fire burns down it's freezing again, because the room's air temperature doesn't really rise.

Also, in summer, I roast in here; the sun beats straight down on the dark felt roof above, and my ceiling is just four layers of felt and a couple of centimetres of plywood, so on sunny days the wood above me reaches 40-50 degrees Celcius and roasts me with infra-red radiation.

BUT NO MORE!

Because over this past summer, I've finished insulating the roof. I did this by getting inch-thick foil-backed foam boards and fixing them between the joists, with twenty centimetres of woolly insulation above that. Here's a few photos to illustrate what I mean, taken when I tested the method at the end of last year:

There's a gap of about five centimetres above the woolly stuff, to allow air to flow. A big danger of sealing a roof up with insulation is that warm, humid air from the room beneath will manage to sneak up, past the insulation, reach the cold area above, and promptly condense, making it nasty and dump up there - leading to the roof rotting. So I left an air gap, and made sure that every area of the roof was ventilated. Since the roof is punctuated by wooden beams, this meant putting an air vent at the top and bottom of each "bay". In the summer, the air rising out of the vents at the upper end of the roof was pretty hot, too, so convection of air along the underside of the hot roof also helps to get rid of heat in the summer.

Thankfully, this meant that I wasn't roasted during the summer; and now I've mainly finished running aluminium tape over all the edges, so my warm air doesn't seep up and dissappear, it's also keeping the heat much better in winter. I've been running the rocket mass heater in the mornings and the room temperature has risen and stayed up for most of the day, thanks to the residual heat from the secondary heat exchanger now being enough to replace heat lost to the outside.

Also, it seems the aluminium tape makes a good electrical contact with the aluminium backing on the foam board, so my entire ceiling is a big radio-frequency reflector, which might prove useful in keeping all the noise-leaking computers in my workshop separate from any antennas I put on the roof...

Redesigning my workspace (by alaric)

So, I work from home - and a lot of my hobbies involve sitting at the same desk, as they're computer-based or electronics-based. My workspace is an outbuilding at the end of my garden, with power and Ethernet connecting it to the house. Half of it is a workshop, and the other half is my computer / electronics lab. The workshop end is pretty good since I made my custom welding bench, but the lab end was just made from furniture I had lying around that fitted in, so has been a compromise for some time. I am forming a plan to fix it!

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Compressed air distribution in the workshop (by alaric)

Up until now, I've just plugged flexible hoses into my compressor to run tools.

I've got a bunch of things that need clean air (spray guns, tyre inflator, the plasma cutter, and a blow gun), and a bunch of things that need lubricated air (nailer, drill, impact screwdriver, sander, angle grinder, chisel, and impact wrench), so I've standardised on using PCL connectors for clean air and the ones that come with cheap air tools from Aldi and Lidl (what is that interface called?) for lubricated air:

To convert from one to t'other, I have my handy compressed air tool caddy. On the front is a regulator, filter, and oil injector, with a PCL plug on the inlet, and on the outlet a springy hose with a shutoff valve and a socket for oiled air:

At the rear is a storage box with my bottle of airline oil, the key for my air drill, the spanners for my air grinder, and a box with a pipette and funnel for putting oil into tools:

Now, this setup is OK, but it's a bit fiddly to go the compressor and plug things in; and I've been making something that needs compressed air as part of the building infrastructure (there will be a blog post focussing on it later so I won't go into detail now, but it's a pneumatic vacuum ejector):

So, it was time to run proper pneumatic plumbing around the place! I had a bunch of copper plumbing pipe left behind by plumbers as we've had a lot of building work lately, so I had some 28mm, 22mm, and normal 15mm tube lying around. I decided to use all the 28mm tube for the long run across the ceiling, all the 22mm tube I had to extend that to make the distance I needed, then 15mm tube for the rest, because larger tube means easier air flow - and because all that volume inside the pipes gives me an extra litre or so of air storage...

To combine them, I had to buy reducers of the appropriate diameters; I went for solder-ring fittings because I'm well equipped with blowtorches. Plastic pipe clips hold it securely to the ceiling beams:

And the 15mm plumbing terminates in things like this:

To convert between the world of plumbing (15mm copper) and the world of compressed air lines (1/4" BSP threads), I searched on eBay and found adapters with 15mm compression fittings on one side and 1/4" BSP on the other end:

• male
• female

The PCL fittings, ball valves, and other hardware came from Airlines Pneumatics.

Now, at various points, I needed to interface to flexible hoses - to connect to the compressor or the plasma cutter, for instance. To do that, I needed to get adapters between barbed hose fittings and 1/4" BSP threads or PCL fittings, as appropriate (all from Airlines Pneumatics). Fitting these correctly needs to be done with care, or they'll leak, so I've made a video explaining the process:

(you can also watch it on YouTube)

Although the fittings are depressingly expensive, it's been very rewarding setting this up - I love working on infrastructure, and now it's a lot easier to use my compressed air equipment 🙂