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Chinchillin

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It seems like the weather is always a theme in Montreal: crazy winters, crazy summers and no spring. After about two weeks of enjoyable temperatures, the mercury has shot up to the mid thirties by late morning and the sub-tropical humidity makes it feel like it is well over forty (that is a Floridian 105 for those south of the border). Seems a like the right time to make a chiller. But not for me, not for the cold-brew or the iced coffee – for the welder!

The new production welder came with two torches: one air-cooled for work below 120 amps and a second water-cooled version in the same form-factor for up to 250 amperes.

It is pretty simple really: cold water goes in one hose, flows through the torch nozzle picking up heat as it goes and comes back on another line. Now, I could have just hooked the cold side up to the tap and dumped the returning hot water down the drain, but a) that would be wasteful, b) there was neither a convenient drain, nor a supply line in the vicinity of the welder and c), if you have been following since this project started, you will know that that just isn’t how we roll :). Besides, it turns out that welding chillers have rather a lot in common with espresso machines. Wait, what?

Above are the essential components of a welding chiller: a heater core from a car, some specialized quick-connectors, a couple of computer fans plus a power supply and a motor and pump from a coffee machine that I just happened to have on the shelf. Chillers, also like espresso machines, are somewhat specialized pieces of gear and, despite their relative simplicity, tend to have a rather hefty price tag. Total cost of the build so far (for the connectors and the heater core): about $45 Canadian.

The first job was to cut off the crimped ends of the inlet and outlet on the heater core and to tap the tubes. I’m not sure what this thing is made of, possibly an amalgamation of aluminum dust and recycled chewing gum, but they actually took enough of a thread to stay leak-free at the very low pressures involved here. Hmm – might not be a good idea to run the pump with the valves closed.

I mounted the fans on a simple wooden flange in an attempt to increase the air through-put and fixed the heater core (aka a radiator) to the opposite side.

As seems to be case with most projects, it is actually the box that is the most work. To speed things up, I chose a material called Alupanel which is a laminate sandwich of plastic inside two thin sheets of aluminum. Because it is mostly plastic, it is very easy to cut, but the ductile aluminum skin allows it to take and maintain a fold. The front panel cutouts:

The flip side is scored on the table saw with about a 1/4″ of saw kerf .

Thirty seconds afterwards, the part is folded up without any tools.

A second panel is cut for the rest of the front and the pump and radiator assembly are mounted on a plywood base board.

The remaining work is really just about hooking everything up. I used a bit of DIN rail that does double duty as cable-guide and structure to connect the front and back panels. The “reservoir” is an 8L plastic jug that the distilled water I bought to fill the machine came in – I was researching 8L containers for camping etc., but then I thought: wait a minute! The plumbing connections are a first draft in this photo. The pump is on the “cold” side of the circuit, so pretty much any kind of material will do for the piping runs – I used 6 and 8mm pneumatic fittings and hose because they are convenient and were on hand. The return side will probably be above the rated temperatures for pneumatic hose, so those are made from slightly sterner stuff – fiber-reinforced vinyl I think.

The hot water return runs through the radiator and dumps back into the top of the reservoir (through a hole in the cap – why make things complicated?).

The supply side, specifically the tiny channels inside the torch, is protected with a simple filter made from a scrap of fine plastic mesh and a few o-rings.

The cover is cut from another piece of Alupanel and, rather than drilling a million holes by hand for air circulation, I riveted some stainless perforated sheet metal (surplace drip trays!) into cutouts on opposite sides.

The tall, rounded slot on the front panel is a sight-gauge for checking the level of the water in the reservoir. The hole on the top, which was supposed to be round but isn’t because my father borrowed the hole-saw kit, is for topping it up with more distilled water. Almost everything here was made with surplus parts and materials (even the Alupanel was actually an old sign), and while it isn’t perhaps the prettiest thing ever and the case took way longer to make than it should have, it might possibly win the “oh I could make one of those” prize for diy/new cost ratio. Actual cash outlay: (quick connectors, the heater core and a couple of plumbing fittings) about $75 CAD (maybe $350 total if you had to buy all the parts). A quick check online for a brand-name version of a similar device: $2600. Now we’re chillin.

1 – image: National Geographic

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What’s in a name?

So, what’s with the name? Lapera means the pear in Italian. It is a nod, of course, to the origins of these fabulous beasts as well as being the name of my existing design company: Pear.

To inaugurate my new home I decided to do something a little special: a coffee machine needs a name, and the name goes on the badge!

We start with a few iddy-biddy single-flute bits and a stack of aluminum blanks.

And a clean vise – you have to maintain your vises in order to maintain your vices. I really should be out-sourcing this part because there are more efficient ways to make it, but, for the first batch at least, these are gonna get made in-house.

A mist setup on the mill keeps the cutter clear of chips. Which isn’t a big deal for the large bit used for the clearing, but is vital for the smallest one which is less than a 1/16″.

The milling path generated by the CAM software is highly satisfying.

Initial machining is done.

Lots and lots of cleaning comes next: rinsing, ultrasonic de-greasing, chemical etch, more rinsing, baking to bring any residual oils to the surface, solvent bath and yet more rinsing.

I borrowed these guns from a friend who “doesn’t miss powder coating”. I completely agree – this process is a hassle to do for large or numerous parts unless you have a really good setup and do it all the time. The guns are fascinating, for a number of reasons, not least of which being that they are the first and only ‘product’ that I have used that is almost entirely manufactured with a plain-old PLA 3D printer.

The powder coat itself looks like pretty dull stuff.

But it sure shines up nice after a quick trip through the oven.

After a quick sanding to reveal the bare metal, a little bit of a trim and a clear coat, the badges are ready to join the fleet.

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Welcome to Lapera – coffee machines made in Montréal’s Mile-End

A simple, beta version of the site is now up and running: just the news and a homepage for now. More things will be added over the next weeks.

A few questions, a few answers:

• When will the machines be ready? – Production is currently underway. Shipping of the first units is still some months away.
• What will the machines cost? – The price will be announced when pre-orders open. This will happen as soon as all of the suppliers are finalized.
• Want to receive updates on the progress towards the launch? – Subscribe to the news list on this page.
• What’s with the ducky? – Hey – why not? : )

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That way madness lies…

Sir Ian McKellen as King Lear. Image source: The Guardian – Photograph: Johan Persson

No, I will weep no more. In such a night
To shut me out? Pour on; I will endure.
In such a night as this? O Regan, Goneril!
Your old kind father, whose frank heart gave all—
O, that way madness lies; let me shun that;
No more of that.

King Lear, Act 3, scene 4, 17–22

The Brugnetti Aurora is my favorite single group vintage espresso machine: minimalist design, bold colors and a fantastic logo in a cousin of the 1962 Eurostyle font. The one in the picture, an HX version, was restored by Orphan Espresso. It was likely assembled and sold in the US by Termozona, an importer from Connecticut who added, what is in my opinion, the criminally design-inappropriate Europa badge on the front.  
 
 
 

Everyone who I have spoken to agrees that they are great machines: simple, well built, small enough for home use, and above all else, capable of producing an incredible shot of espresso. They are, however, rare. The original Sr. Brugnetti closed down and liquidated his factory before the brand was relaunched under new management after a five year hiatus. Brugnetti no longer makes lever machines and I presume that the original group head molds, manufactured by them or a supplier (Tortorelli Meccanica in Sienna?), either no longer exist or would be impossible to track down with my hundred words of Italian.

The heart of the matter is the lever group and the heart of the group is the group body which is a complicated part. So the million dollar question is what would it take to reproduce it?


References

A discussion of building a lever machine from scratch with reference to the Aurora. thread discussing the origins, shrouded in myth, of the machine. Another couple of restorations of the European Aurora from kaffee-netz in Germany are here and here.

A restoration of a two group model – surely not an original case?