Another sausageBot session

Had another good sausagebot curing chamber controller session tonight with Spandex. We’ve got the enclosure almost completed now and it’s starting to come together really well. Still need to work out exactly how to fix the lid on properly, but the tabbed corner pieces are all glued together and the base and sides too. I think the next job is to start wiring all the innards up and testing it before we finalise the enclosure structure as we know it’ll look sweet once complete.

Some pics of tonight’s progress…

sausagebot top off front view

sausagebot top off front view

sausagebot top off rear view

sausagebot top off rear view

Top on front view - sexy!

Top on front view – sexy!

Next time we’ll get all the innards fixed into place then onto testing and software development 🙂 It occurred to us tonight that we’ve spent an inordinate amount of time designing and building the enclosure but it’s time well spent I think. The really exciting stuff is up next!

sausageBot enclosure progress

Looks pretty good!

Looks pretty good!

You can’t really see the base on the picture above due to the white table, but you get the idea. We laser cut all the enclosure parts last night – apart from the lid. We accidentally used the wrong piece of perspex for the base, which meant we didn’t have enough left to make it! Oh well.

Laser cut the corner blocks

This laser cutter really is magic

Here’s what the corner blocks look like when they come off the cutter. The pegs cut out from the middle are used to fix them together.

Corner blocks

This gives you an idea how the corner blocks fit together

One of the side panels

One of the side panels with passive cooling vents. The base also has these vents cut into it

Side panel with blocks

Side panel with blocks. Those tabs fit perfectly into the slots.

The next job is to glue the corner blocks together, then fix all the electronic components and the relays to the base, and build the “walls” – i.e. everything apart from the lid. Once that’s done we can wire it all up and start running some tests and writing the software.

This thing really is complete overkill for curing a few sausages, but it’s gonna be bloody great when it’s finished 🙂

Mini Sausagebot update

Had another sausageBot (curing fridge controller) build session with Spandex at the Nottingham Hackspace last night. We wanted to cut out the sides and  top and bottom panels but the laser cutter was occupied all night. We did manage to drill a hole in the back panel which was far too big for the remote sensor plug (thanks, Maplin advice person! 19mm, my arse!) – I guess we should have actually measured it to confirm, but hey. Ended up gluing that in the end – still looks OK, luckily:

Rear sensor DIN plug

Rear sensor DIN plug

Oh, and the front panel now also has the potentiometers fitted to the silver dials for altering the temperature and humidity set values, and coloured LEDs to show which relays are currently open: blue = fridge (cold), red = heater, green = humidifier, yellow = dehumidifier.

Front panel with status LEDs

Front panel with status LEDs

In the next build session we’ll try to get the remaining enclosure parts built and assembled 🙂

Soldering station action shot

Bonus soldering station action shot!

SausageBot progress

SausageBot panels

SausageBot panels  – just look at them!

Got the front and back panels sorted today. After work I drove over to Matt Spandex’s house to continue on the sausageBot curing fridge project. We already had some of the main parts bought and assembled, and so after a delicious, unexpected fish supper (thanks, Frances!) we drove to Nottingham hackspace to use their laser cutter for the front and back panels. Spandy had already designed the layout of the panels to fit the components as you can see in this post

I hadn’t been to the hackspace before and it’s great. You pay a subscription (whatever amount you like actually), and you can use what you need, as and when you need it. It’s the first floor of an old Victorian warehouse, kitted out with all manner of tools from cnc machines, laser cutters, lathes, soldering stations, and so on. Pretty much everything. It was fairly busy when we got there, but there’s plenty of room and noone using the laser cutter – result! So after about an hour trying to figure out how to import the sketches of the panels into the laptop hooked up to the laser cutter, we were in business.

The laser cutter is magic. Did we place the acrylic in the right place not to screw it all up? You’re damn right we did.

Anyway, here are the results from tonight’s session. I’m seriously impressed with the accuracy of this thing. All the components just clipped right into the holes! Kudos to Spandy, again for the design work 🙂

Front and back panels laser cut

Front and back panels laser cut

rear panel with power sockets fitted

rear panel with power sockets fitted

Fitting various components

Fitting various components

Front panel with knobs and screen!

Front panel with knobs and screen!

That green switch on the right hand side is pretty sexy, and it will light up when it’s on. It’s so satisfying to click on and off that I might have to duct tape it on in case I get tempted when actually in production.

Anyway, the next job is to get all the relays glued (or fixed somehow) to the base of the enclosure, fit the status LEDs (those are the 4 holes on the front panel with nothing in at the moment), wire it all up, then plug everything else in (fridge, humidifier, heater, etc)

I really can’t wait! Stay tuned….

Building a dry curing chamber

I’m building a dry curing chamber out of a fridge – for fermented sausages and drying cured meats. This means I can make salami, guanciale, coppa and all the other really good stuff.

When you’re hanging meats to dry them (prosciutto, for example) you need the relative humidity to be about 70%RH, and the temperature in the region of 12-15C, warmer and wetter than most fridges are prepared to run, so you need some additional equipment to maintain these parameters. We don’t have ideal conditions in the UK to do this without a little gadgetry.

I won’t go over all the ins and outs of how to do this here – these guys have done it all before and are the authority on it as far as I can see:

Look at all that beautiful stuff they make. mmmmm.

Anyway, I bought a large fridge, here it is:

My soon to be Curing fridge

My soon to be Curing fridge

Should have enough room in there!

I also bought a reptile vivarium controller which monitors and controls temperature and humidity, and an ultrasonic humidifier. I plugged all this in to see how it would work without anything sausagey hanging in there. I set the temperature to 13C, and the variance to 2C. This means that the fridge compressor starts when the temperature gets up to 15C, and stops cooling when it hits 11C. Simple enough. But temperature control is the easy part.

Controlling relative humidity is far more tricky. When running empty, the humidity in the chamber was all over the place, going from too high, to far too low. Hardly ideal, and would have ended up ruining quite a lot of potentially tasty meat.

So I made a sacrificial batch of Mexican style chorizo to test out the chamber’s drying capabilities. This cold-smoked chorizo only needed to hang for about a week, long enough for me to work out how well / terribly it might behave.

I hung up the sausages and began monitoring. They hung  in there for a week and by that time they’d lost roughly 20% weight. But the humidity was still all over the place so for things which need much longer drying times this might not end well.

Here they are after being hung – I’ll make another post about how I made them at some point.

Cold smoked chorizo after hanging

Cold smoked chorizo after hanging

But I need more flexibility and control.

I was chatting all this through with my friend Spandex – (he is both tall and wise) –  and he said, “Someone must have done this with Arduino before”. I’d heard of Arduino before but never had experience with home electronics projects (other than building PCs), and the thought of wiring up mains appliances to relays is frankly pretty terrifying. He makes a lot of cool modular synth stuff so it’s right up his street.

So we hatched a plan to build a “sausageBot” – an Arduino-based controller which will monitor everything via sensors, and control all the equipment through relays. Spandex will be doing all the wiring and soldering and I’ll be asking daft questions and thinking about meat.

In return I have offered to pay him in cured meats. What a winner.

Here are a couple of mock-ups of how the case for sausageBot might look once finished:

Enclosure mockup - front

Enclosure mockup – front

Enclosure mockup - top

Enclosure mockup – top

last night we started to build the innards.

We went for a “let’s put something together and see what happens” approach. We’ve got a basic layout on breadboard, with the arduino reading temperature and humidity from the sensor, and we’ve also wired up the circuit for the first relay. Exciting stuff!

Sausagebot breadboard test

Sausagebot breadboard test

Temperature and humidity values being recorded

It’s alive!

It’s obviously very early days but exciting nonetheless. Will post more progress when there’s some to show 🙂