Author Archive for Richard Jack

19
Jul
12

Feijoa Brandy

I’m making some feijoa brandy at the moment. Bloody busy, but the seasons wait for no man, and the wine had been fermented and sitting on the pulp for ages, so I had a late night session on it last night with a couple of stills.
Recipe was as simple as possible:

  1. Apply stainless paint mixer and power drill to feijoas,
  2. Add pectinase and yeast,
  3. Let the drama build.

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The pulp is a bit of a bastard to press – such a fine grit in that stuff around the skins. It’s much harder work than apples.

The product is still at the low wines stage right now, awaiting the final run, but I’m thinking it will probably be kept in the white at ~50%ABV. Some crazy bloody smells in places through the run, some of the mid tails is like burning plastic. Fores and heads are like feijoa essence, hearts kinda lemony. Interesting challenge in cutting this to come I suppose!
some piccies:

Press in all it’s glory:

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Making do without my hydraulic jack:

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Dry pulp

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Pot still running with some amazingly half-arsed insulation (i.e. I stole the dog’s towel)

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I’m looking forward to the results of a spirit run!

30
Apr
12

making a boil ball / gin basket, part 1

I’ve been having trouble getting enough botanicals into my 2” pot still column for decent vapour infusion batches, so the 4” pot config is going to have a dedicated 8” basket. By putting a triclamp sight glass in it, I’ll also be able to use it as a fill port for running back to back runs without taking down the head – once I get my boiler drain, that is! It will also work as a boil ball for stripping foaming washes like malt or rum – the slower vapour speed in the ball should help bubbles collapse and fall back down the column, and the sight glass will let me see it happening.

I did all my brazing for it this weekend. There’s a bit of touching up of the soldering and I need to buy a lens for the sight glass, but the bulk of the work is done.

The starting point was an 8” copper sphere, 10cm of 4” copper pipe, a couple of triclamp flanges modified on the lathe to fit the pipe, and a 2.5” triclamp flange to use as the sight glass.

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Firstly I sanded the 4” stainless flanges to rough them up a bit, fluxed them well, and then seated them on the pipe. you’ll note I didn’t clean the copper – I’m finding it easier to keep the Silfos 15 solder I’m using from running all over it this way.

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After brazing with the oxy acetylene torch it was predictably ugly…

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But it cleaned up nicely:

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And then I split it on the bandsaw. I joined both ferrules on first to save doing the heat up of the workpiece twice.

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Starting to take shape…

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Sorry for the shoddy photo – it’s important to drill a hole in a sphere before heating it, otherwise it will be pressurised.

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The heat I needed for my Silfos 15 rods was unfortunately such that the soft soldered seam in the centre of the ball melted and parted, Which actually worked out pretty well for me as I could use a hole saw to open the column ports while it was in half – much easier than trying to hold a sphere securely. these are tidied up with a half-round file later – couldn’t find the bloody die grinder!

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I then filed and sanded off the original soft solder in the sphere seam, and rebrazed the sphere together with Silfos. I made a bit of a mistake here, I didn’t account for the thinner wall of the sphere relative to the pipe, and used way, way too big a torch tip. Too much heat meant a messy seam.

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Right, sphere complete so time to put that sight glass on. After the seam experience I didn’t fancy brazing stainless straight to such thin walled copper, so I put a very short length of copper pipe on the ferrule first:

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Then it was brazing time again:

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After a bit of cleanup:

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After a lot more cleanup:

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Still some solder cleanup to do on the centre seam and around the sight glass port that I can’t reach with any tools, so I guess I’ll have to do it by hand… Sigh… No one will ever call my metalwork pretty, but I was glad to get it all done in a day! Also still to come is a stainless mesh screen in the bottom for the botanicals to rest on.

25
Apr
12

Fruits of the cider press labour

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A 220l ex Chardonnay barrel, under the house to sleep over the winter. The best thing is that we get to reuse the barrel afterwards! Very exciting.

The airlock on the barrel is there because we primed the barrel with a bit of fresh juice when filling to take care of any oxygen I the process. It also got a co2 scrub to reduce h2s.

I can’t wait to sample it!

15
Apr
12

Partigyle Brew Day photos – Imperial fig stout / export stout

So, there is a lot going on in the shed at the moment. It’s messy. I apologise. I’m still processing some fruit (feijoas next, and maybe olives) and I’m testing out the new 4” potstill in various configurations before finishing off my scotch. Full post on that to come later. Amongst this I’m still brewing much more beer than I can drink (what a problem, eh?) and todays brew is probably interesting enough both technically and in the recipe to warrant a post.

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First of all, the technique. Partigyle brewing refers to keeping the first, second, and sometimes third runnings off the mash separate, making two or three beers of sequentially decreasing strength from the single mash. This is a traditional English technique, and many styles we know today have their roots in this brewing method – e.g. ESB, Best bitter, and Ordinary Bitter. To learn more about the technique, and how to do it at home, this article by Randy Mosher (and the attached gravity and colour tables) should fill in the blanks, but I’ll quickly summarise how I plan on doing it:

  1. Mash enough grain for 2 batches of beer, calculating the expected split of gravities from the table linked to above,
  2. Mash out first runnings into the first kettle, get the boil going, and proceed as normal with the rest of the first brew;
  3. Batch sparge into a second kettle, correct colour with additional roasted malts, mash out, take a gravity reading to check how long a boil is needed, then proceed as normal for the rest of the second brew.

Just to make it even more interesting, my second beer will be done using the no-chill technique. more on that later.

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So, on to the recipe – this is what I came up with:

Batch:
40L batch size, 2 runoffs, ~80% brewhouse efficiency

Grain Bill:
8 kg NZ Malteurop ale base malt (3.5 SRM)
1kg Bairds Pale Chocolate malt
1kg Oats, flaked (cereal mashed)
0.8kg Thomas Faucet Dark Crystal malt
0.2kg Bairds Chocolate Malt
0.2kg Roasted Barley
0.15kg Weyermann Caraaroma
0.15kg  Weyermann Caraamber

Figs,other awesome stuff:

Imperial stout (Figaro):
1.5kg figs, caramelised, added to boil
80g Switch Espresso Ethiopian (added in cold conditioning, 4 days at 1°C)
20g Cocoa Nibs (added in cold conditioning, 4 days at 1°C)

Export Stout
Potentially this might end up as a milk chocolate stout, haven’t decided yet, but it would be:
120g Cocoa Nibs (added in cold conditioning, 4 days at 1°C)
400g Lactose
Vanilla?

Hops:
Imperial Fig Stout-
70g NZ Cascade (8%) @ 60 mins, 63 IBU
60g NZ Cascade (8%) @ flameout
20g Simcoe (13%) @ flameout

Export Stout-
80g Willamette @ 60 mins
30g Willamette @ flameout (nochill cube)

Yeasts:
Imperial: Wyeast 1272 (American Ale II)
Export: Nottingham

Right, so those in the know will probably notice some similarities in the shopping list with the Epicurean, which is true, because this is definitely inspired by that beer, although I want to go a lot more figgy and less coffee, to the point that I’m not putting coffee in at all at this stage – some cold extract  or dry beans might go in later in the piece though, potentially with cocoa nibs as well but that’s a later question, after I’ve tasted it. [editing this later, yeah, they went in, moar flavour mwhahahaha]

Starter

First think I had to do was get a starter going from my 1272 slurry. I stepped this up over a few days before brewday on my DIY stir plate. A stir plate is such a great investment, they’re cheap to make and you can breed up yeast so much easier – and stop paying for it. Here in NZ, we also have the problem that liquid yeasts are pretty unavailable, so being able to easily breed up a sample to pitching size is great.

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Roasting Figs

I got about 1.5 kilos of figs from Raffe, and dry roasted them for about 3 hours at 120°C, then mashed them, then grilled them for 30 mins or so at 190°C. They rendered down into a super gooey caramel sludge. Awesome smells.

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Weighing out grain

I have a couple of different sets of scales. For my base malts I use a nice pair of Salter analogue scales I put an old retired fermenter on and pour into. Nice and inaccurate, but I figure with the base malts it’s just a gravity point here or there, I wouldn’t pick it in the end product. For the specialty grains, I tend to use a little set of 1g resolution digital scales and be a bit more precise about it.

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Milling Grain

I mill directly into my mash tun, which is of the cooler / esky / chilly bin and stainless braid persuasion. My mill is a Crank and Stein 2”, gets a nice crush and with the hopper I built and a step down motor attached, I can just pour the grain in and walk away.

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Heating strike water

This is my number one brewing-quality-of-life improver: A thermostatically controlled hot liquor tun (HLT). I have a 2.5kW element welded into the keg, controlled by a cheap ebay thermostat (same as I use on my fridges for fermentation control) and one of those plug in timer socket things. A sight glass on the side gives me my volume measurements.

Because of the thermostat and timer, I can fill up my HLT the night before brewing, add a tiny bit of a campden tablet for dechlorination, go to work in the morning, and come home to perfect strike water ready for me to mash in with. It’s been a great help in my quest to brew on weeknights.

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Water Chemistry

I have a very low mineral supply of water, which is great for brewing because it’s very easy to build up to whatever you want. I use some drug dealer scales and a combination of Epsom salts (MgSO4), Gypsum (CaSO4), Chalk (CaCO3), Calcium Chloride (why the hell doesn’t that one have a catchy name?), baking soda (Na2CO3), and salt (NaCl) to correct my water profile to whatever I decide I want on the day. Generally, you want to correct the pH to an appropriate level for mashing (5.2), and then vary the relative levels of sodium, chloride, and sulphates to swing the perception of the beer from malty-sweet to bitter depending on what you’re after.

Alternatively, you can aim to match a famous water – like Dublin for a stout (lots of carbonates to buffer the acidity in a dark mash), or Burton on Trent for a English IPA (oodles of sulphites for dry hoppy bitterness).

I normally make up my own profile on the day because I’m incapable of following even my own recipes, let alone anyone else’s!

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Mashing in

I don’t use pumps in my brewing, just gravity, so I simply drain the water from my hot liquor tun into the mash tun at the right temperature, and then give it a good stir and chase down all the little dough balls and squash them. Single infusion mashing (i.e. add water @ certain temp and forget about it for an hour) is pretty simple and easy really, no matter how much we like to complicate it when talking smack about brewing.

My mash tun is pretty close to capacity on a partigyle batch like this. It’s also always a little scary working with oats in the mash, as they are notorious for giving you a “stuck sparge”, where the filter/manifold in the bottom of the tun clogs and ruins your day. I try to avoid this by doing a separate cereal mash on the oats upstairs on the stove, where I can do all the protein rests etc with a bit more precision.

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Vorlauf…

… Is a fancy word for pouring some wort out of the mash tun and then putting it back in the top without splashing too much. The idea is to set the grain bed in the tun into a big filter matrix to help get clearer wort into the kettle. I basically did this out of habit, without thinking that the beer is actually going to be about as clear as engine oil due to colour alone.

I just run off into a jug and then pour it back into the tun over my mash paddle. Fancier setups would do this with a pump.

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Mashout / First runnings

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Figs!

During the first runnings I’m going to sort out my figs. They’ve been chilled overnight after roasting, and they have basically been rendered into figgy treacle. It tastes like awesome.

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I have this big reel of muslin cloth for the cider press, but I’m also using it for hop bags and such in my beer making. I reckon it’ll be perfect for holding the solids back of the figs while the caramel and sugars can steep out into the boil.

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I bagged up the figs with plenty of room to spare, I don’t want them tightly packed.

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In goes the yumminess…

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They’re tied to the rim of the kettle to eliminate the slim chance of any scorching to the bottom of the pot.

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Batch sparge, second runnings / gyle

After getting the first runnings into the boiler, it’s time to batch sparge – add more water to the mash tun to wash out some more sugars. In a normal brew this would go into the same kettle, but in the partiglye method, I’ll be draining to a different kettle and making a smaller (weaker) beer with the second runnings.

I’m going to darken the second runnings somewhat by adding a little Carafa Special II (a dark roasted malt with the husks removed to avoid astringent flavours), which I’m just going to crush by hand, it’s too small a quantity to bother with the mill.

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I’m going to dump the carafa into the mash tun. The 10-15 minute or so steep should extract what I want just fine.

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The sparge water is added to the mash tun at about 76°C. I feed my water in through the braid filter at the bottom of the tun, which I’ve recently discovered is unusual.

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After a 10-15 minute or so wait, I vorlauf again, then mash out into a second kettle – my hot liquor tun is done for the day so I’m using it, with it’s 3kW element it can just give a good enough boil.

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Hops

I weigh out my hops on a 1g resolution set of scales, and then make a hop bag out of muslin cloth for adding them to the boiler, much the same as how I added the figs.

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While I’m hopping the imperial stout, the export stout is getting to the boil:

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Checking Specific Gravity, blending

I recently got a refractometer. How did I live without one of these? I’ve broken so many hydrometers that I should have bought one right at the start, it would have gotten cheaper pretty quickly.

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Anyway, I tried to take a photo down the… Uh… Lens? Scope? To show the gravity reading. It sort of worked, but it’s not as clear a line as it is to the eye. I did a bit of blending between the two gyles (first and second runnings) to adjust the gravity south a little in my imperial stout – I didn’t want it to be too imperial. Having a refractometer that can test little samples during the boil without cooling down 100mls or so is a serious plus. This pic is taken during blending, the first runnings gravity was much higher than this.

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flameout

With the imperial stout getting pretty close to flameout, my immersion chiller goes into the boil to sanitise it, and aroma hops etc are added, and some koppafloc finings (again, habit).

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When the boil is over, I run cold water into the chiller and then out into my mash tun to use for cleaning, which seems better than tipping boiling water down the drains. I cover the kettle with plastic after the first few minutes of chilling.

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Racking to the fermenter

With the imperial stout chilled, I can rack to the fermenter. Again, gravity feed is how I roll so I just lift up the kettle and put it on my keg freezer, and rack to a plastic fermenter.

Meanwhile the other boiler is boiling away, almost done now.

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No Chill, Cube hops

No chill brewing is (according to legend) what the aussies came up with to combat high groundwater temps that mean you can’t chill right down to pitching. Or scarce water, or something.

In summary, you rack boiling wort directly from the boiler into a HDPE jerry can or “cube” and seal it up. It’s then more or less shelf stable wort – it cools naturally and you can open it up at a later date and ferment. I was pretty sceptical about this because of my fear of DMS (off flavour like cooked corn / cabbage resulting from poor boils), but it seems to be well and truly established now that no chill brewing doesn’t cause DMS. Also, you continue to get hop utilisation as it cools in the cube, so you need to advance the hop additions by 10-15 minutes or so – so I’m adding what would have been a 15 minute addition into the cube before racking onto it.

Some more info about no chill brewing is here.

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Hot wort then gets racked into the cube…

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You squeeze out any air and tighten the lid. Too easy. It now awaits me getting around to ferment it. This saves me from having two stouts on tap at once, and helps manage the fermenting pipeline. It’s a pretty neat trick really, I’ve been using it a lot to piggy back a second beer onto a brew day.

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So there we have it. Imperial stout into the fermenting fridge (Thermostatically controlled) and the export or maybe milk chocolate stout into a no chill cube for me to deal with later.

As I write this, the Imperial stout has been fermented and kegged, and I can let you know that it rocks the partigyle. Teheheehehehehe.

Can’t wait to brew this recipe again, but I’ll have to, because there aren’t any more figs til next year.

Cheers.

06
Mar
12

Building a cider press

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The press

 

the problem

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That's... Quite a lot of apples.

So, someone gave me about tonne of apples for “personal use”. I really need to get better at saying no to free stuff. I left maybe 300kg behind (showing huge restraint right there) so only ended up with a meagre ~900kg of apples… And no equipment to deal with them.

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The getaway

First of all, I blasted up the apples with a sharpened paint / mortar mixer on a grunty drill (highly effective, cheaper than dedicated equipment) and stuck the pulp in sacks in a couple of chest freezers to buy myself some sea room while I build a press. This lets me smash (“scratter”, I guess) apples in about 50-60kg batches, and at the same time I added pectinase to get me better extraction down the line.

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Sharpened paint mixer

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The crush

The pulp went into plastic sacks and got frozen (took forever to freeze in the middle) and, having made an enormous, icy, apple flavoured problem for myself, I started to think about a press… We’re not going to dwell on how hard it was to get the sacks back out of the freezer, that chapter is best forgotten.

Materials, goals…

I don’t really drink much cider so I wanted to do this on a shoestring budget. So, paying lots for materials was out. For the frame, I recycled some European pine bearers that had been shipped to NZ as packing material for some large machines (this is low grade core material, which is why you’ll notice fairly extensive cracking in later photos).

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Because this is such a low grade material, I don’t want to rely on it for strength, so I scrounged some scrap angle iron, steel flat bar, and threaded rod to reinforce the wood with. The wood still provides a nice aesthetic and good “spring” in the press, but the main loading is all on the steel. Bolts were scavenged from the same place as the wood.

For the basket and drain I selected NZ Macrocarpa that I can get in a rough sawn clear grade from a local mill, then do the ripping / dressing myself. I cut a corner on the basket construction and used aluminium flat bar for the hoops instead of stainless, because that’s what I had. Hopefully I don’t pay for that later! The drain tray is stainless sheet from a scrap dealer, with a bit of tig work done by a friend and a stub of stainless pipe sawn off an old keg stem. I had to actually buy stainless screws (Shock, horror) and some worktop oil for fixing and sealing the basket and drain. The basket is lined with muslin cloth during pressing, which cost 20 bucks for about 70m.

I wasn’t going to piss around making those mincy little presses you see in homebrew shop that take 5 – 20L of pulp per press cycle, so I settled on an 80L press capacity. I figure that it can be reasonably efficient with a 50L pulp load, which will be ideal for other home brewers to use to get their 30L fermenter full, and also will be time effective for the odd crazy person like me who needs reasonable production out of it. It needed to be able to fit in my car once done with minimal deconstruction, be set up in a standard stud height garage, while the drain needed to be at least high enough for a 30l fermenter, and preferably high enough for my 75l fermenters too.

I apologise in advance for having made no plans whatsoever for others to follow, but I figure there are plans out there for those that need them. This is just my made up as I go along design.

Building

The basket

I decided to start with the basket. I used a panel saw and a 4-sider to make my staves out of rough sawn boards.

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Crosscutting on the panel saw

Quite nice grain in there under all the surface damage from the mill.

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Macrocarpa end grain

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Macrocarpa grain again

To the four sider:

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The foursider I'm using - Weinig Cube

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I quite like having the machine do all the work

This thing is pretty sweet. It’s a little baby foursider for joinery shops and so on. It projects the spindle settings out onto the workpiece with lasers. Everything is better with lasers. And this is much less scary to use than a jointer + thicknesser.

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Cube controls

I processed a bit extra while I was at this for making the drain. More on that later.

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Dressed and sized staves

Right, so I’ve got all my staves, dressed and squared, so it’s time to oil them.

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Oiling time

I did one coat an evening for a couple of days.

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Like watching paint dry

I drilled out a good spacing on my flat bars (soon to be hoops) with a drill press, aiming to have about 10mm between the staves at the inside of the basket after forming it into a cylinder. I taped the bars together for this so they’d all be dead on, no crooked staves.

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Everyone needs a drill press

With the hoops accurately drilled, I could start assembling the basket. The screws are stainless self tappers.

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Just like a railway track…

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Stupidly resting freshly oiled wood on metal swarf...

I left plenty of overlap, for weldng the bands after shaping, then set about to making it round. I found that ratchet load binders worked well for this, combined with a bit of brute force.

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Load binders are rapidly replacing duct tape in my 2-tool tool box

I dismantled the basket, then the hoops were TIG welded by a friend…

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I need to learn to TIG...

And given a brush finish,

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I tried way to hard to mechanise this before doing it the old fashioned way

Then the whole thing was put back together again.

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Just like Humpty Dumpty only successful

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About this point I was cursing Pozidrive screws

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voila

Basket done. It’s not a perfect cylinder but close enough. I reckon a few press cycles should sort that out anyway.

The Drain

The drain is what the basket sits on, and what channels the juice into the output vessel. Because I was building a reasonably large basket, I wasn’t happy with the idea of the press load sitting directly flat stainless pan – it would be hard for the juice to flow out.

Right?

Right.

Having decided that this was a problem (with little-to-no research), I set about making a solution out of wood. I needed a slatted tray to press against, but juice needed to be free to flow out between the slats. This is the [potentially over complicated and fragile] answer I came up with.

I took some of the same material that I made the staves with, and thinned it down a touch with the foursider – no reason to take up more height than is absolutely necessary here, because it’ll just make the overall height taller and more awkward. Then I thinned down a few lengths even more, and went to the band saw and started cross cutting:

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Crosscutting on the bandsaw

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I could use this stuff for Jenga...

The idea mocked up, sitting upside down in the stainless drain pan (which has been tig welded by this point):

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This is starting to look like a fiddly job...

Then I got to gluing and clamping, which was a bit tedious. I have these neat clamps to use though which clamp across and down at the same time, that made it easier. By gluing it upside down I was able to get a roughly level top surface (bottom surface in the clamps). The slats will be in compression (i.e. completely supported) during operation, and the shear stress on each glue joint should (he says, with absolutely nothing to back it up other than the fact that I’ve done it now) be low enough for the glue to hold the spacers in place. I used a structural grade PVA, it’s MSDS checked out alright for this application, but do check out glues before using them in potential contact with food / drink.

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These are "frontline" clamps if you're wondering

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Much nicer than sash clamps, But I did need to use some wood as spacers as they're designed for thicker workpieces than this.

I left the work clamped overnight, and in the morning…

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Bit of glue to clean up...

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This shows how the juice will run underneath the spacers

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On the stainless drain pan

It worked! A bit of orbital sanding on the top to sort out the glue squeeze out, and the same oil as the basket, and it was good to go.

Press Board

I found an old 8 ton hydraulic jack to use for the press power. But you still need a press board to act like a piston head. I decided that I would rip up some more macrocarpa, joint it with a Hoffman jointer (dovetail keys) and then cross laminate it so I still get good strength out at the edges.

So, back to the panel saw to cut the main boards, and measure out my hoffman joint locations…

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I <3 the panel saw

… And then over to the hoffman jointer…

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Fortunately there was a box of dovetail keys sitting next to it...

This is how they work:

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It's a bit tricky to get these totally lined up when the machine is missing a stop.

Having routed all the joints I started gluing and jointing:

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Ready to glue

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Using plenty of glue

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I try to get a good spread before clamping

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Almost there

And then the whole lot was clamped up overnight.

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Totally should have used the other clamps for this...

With got the main boards jointed and glued, it was time to cross laminate a layer across it. In an ideal world I’d laminate a layer above and a layer below, to balance the compression and tension in the grain across opposite sides, but I ran out of wood…

I ran the timber through a thicknesser to get it even, and also ran the previous lamination through at the same time:

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Foursider was unavailable

Then got out the cool clamps again, glued and clamped the layers together. Because the new, unlaminated layer is wider than the other layer, I can do both with grain and cross grain lamination at the same time:

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Doing the butt joint first

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Then glueing the cross lamination

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Again with the spreading

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The previous lamination goes on, cross grain. I've placed it with the hoffman keys in the center to keep them out of sight.

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These really are a better way to clamp.

After the work had been clamped overnight, I chucked it on a CNC router and set fire to the machine by using the wrong cutter milled out the cross laminated board into a circle, sized to have about 5mm clearance inside the basket.

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Pay no attention to the smouldering mess on the floor

With a bit of sanding and a coat or 3 of worktop oil to seal, the press plate was done, although I find it hard to resist putting it in my kitchen and using it as a chopping board.

The Press Frame

So, with all the hard stuff done, I just needed to build a frame to hold it all together! I have to apologise about the standard of photos for this section, my DSLR was elsewhere for this section. Good thing it’s the more boring part.

I cut all my pine beams down on the panel saw. They are so hopeless twisted from drying too fast that I didn’t even bother trying to straighten them on the foursider – I would have lost too much wood.

I misused the panel saw to save me some work with the bandsaw (I would have had to assemble one) – bit naughty, don’t try this at home, etc. I was wanting to make a couple of half-lap joints for the drain bearers and a kind of bastardised tenon for the feet.

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The drain bearers - the fit is good enough that with the steel reinforcing in place, they stay on with friction alone.

I cut up, cleaned, welded, and etch primed my steel reinforcing to take the load under the drain bearers (the cross members in the above image), and above and below the press bar (below basically just to stop the jack damaging the wood, top to take most of the stain). I used some offcuts of the angle iron as fixtures to attach the press bar to the uprights.

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Sizing my DIY bracket fixture thingies

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Laying out the drain bearer steel prior to welding

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Vinyl etch priming the steel post welding

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Checking all my sizing prior to drilling

From the above image I’m sure you can guess how the drain bearers were supported, but the press bar assembly might be a bit cryptic so this should explain it:

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Press bar assembly - when assembled, "up" is right in the photo.

There is steel flat bar both above and below the press bar, and angle iron masquerading as a fixture on top to screw through into the uprights. I used flat bar here because I want this to have a bit of movement in it, so that I can load up pressure on it and have to pump the jack less frequently.

I drilled the steel so I could run threaded steel rods between the press bar and the drain bearers – this is of course where most of the pressing force is loading, so it’s nice to have all of this load going through metal rather than dodgy recycled wood.

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Drilling the hole for the threaded steel tension rods

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more mock up size checking

I hit a minor problem when I found that my threaded rods were not quite long enough, so rather than buy some more, I made up a couple of little connecters on the lathe:

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All the best things in life are free, like threaded galv. rods in inconvenient 1m lengths

Then I cut one rod to size the hard way:

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Hacksaw = slow

After which I kicked myself, and cut the second one the easy way:

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Angle grinder = fast

In order to get the whole thing just a bit more attractive, I rounded the edges of the wooden sections with a corner rounding router bit and a router table…

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Router table. Totally unnecessary, could have just used the router by hand and made less mess.

The frame wood all got oiled with a product called CD50…

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Making a mess...

And I put the whole thing together:

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Holy crap I made a press

It lies flat in my car with the feet taken off, so I got it home and started using it. Note the use of a bit of plastic food wrap around the basket to prevent any squirts from making a mess. I wouldn’t bother if I was outside, I just don’t want ants and wild apple ferments where I brew…

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Super easy to use with that much grunt in the hydraulic jack

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Working well

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Other side

It works great! We’re getting 70%+ extraction by weight on the thawed pulp. We could probably go higher but the apples are free and plentiful, so we aren’t using too much time going for the last 5%. The first 25l of juice literally falls out of the press without even engaging the jack.

I don’t really have a fair measure of how long a press cycle takes, as I’ve been drinking and chatting etc every time we’ve used it so far, but it’s probably about 20 minutes if you were paying attention, maybe a bit longer. One thing I can say for sure is that it takes a lot longer if you haven’t used pectinase, and the extraction is much worse.

The first load of cider is going into a 220L ex-wine barrel to age til next summer, and the remainder will be a few experiments with French style cider and berry ciders, with the balance to be fermented on the pulp and pressed post-fermentation for calvados – and maybe a fruit based neutral from absinth! I also want to experiment with using the pressed pulp (“cheese” is the correct term I’m told) with dextrose added to see if I can’t make a grappa-like spirit out of apple waste. I’ve got a 50L carboy that is just begging to be used for “keeving” the french cider.

Cheers.

05
Jun
11

Uh… Sort of forgot to say what I’m actually building…

It’s been gently brought to my attention that I haven’t really explained what the hell I’m up to. I kind of started writing that last post without considering the fact that not everyone has been rolling the design around in their head for the last year… I’m trying to create a very modular collection of parts that can assemble into a variety of different arrangements, but for now we’ll just look at the two extremes. The full reflux column and the pot still.

The column is going to look a little like this:

The full reflux column

Experienced distillers amongst you may be saying “um, wtf are you doing?”, so let me explain the design.

For a start, if I want to go commercial, I’ll need a good supply of neutral to experiment with, without having to spend a whole weekend to do a run to get it. So, an upgrade from 52mm (say a generous 2.5l/hr @aezotrope) to 103mm diameter column, which should do at least 8l/hr if I can get enough heat input to it. This will mean I spend less time making ethanol and more time crafting flavoured spirits.

A standard VM

Secondly, I want to try and build a new type of head on the still to see if some more control can be eeked out of the vapour management design. Currently, a VM relies on turbulence and ethanol density to get a vapour split between the overhead reflux condenser (which will return reflux back down the column) and the takeoff port, which leads to the product condenser. While this way of doing business has some serious advantages that I won’t go into right now (see this thread I wrote on home distiller to understand more), the big disadvantage to this is it’s very hard to run in low reflux operation – say for flavoured spirits. I want it to work differently.

Instead of  using a passive split, I want to force the vapour to split between two ports that resize in tandem – If I want to set reflux to 75%, the product should then be 50%. I also want to be able to completely shut down reflux and run as a tall columned pot still. The easy way to do this would be to have two valves. However, that would break a golden rule – never build a system that could allow the still to build pressure. It must always, always be open to the atmosphere.

So, I’m going to put a cross pipe through the column at the top with an aperture cut into it. A machined copper plate will slide along inside it to change the vapour split. It will have a teflon braid (safe with hot ethanol) seal around it. This should force a vapour split, and allow me to “dial in” a specific reflux ratio. This isn’t all my idea, I’ve had help from a lot of people, most notably Harry Jackson for the concept of a forced VM, and Airhill on Artisan-Distiller.net for brainstorming ideas of how to actually accomplish it.

An illustration of my splitting valve concept

Note that these illustrations don’t actually show all the pipes – the plumbing of the cooling and reflux circuits is excluded.

The split will control the flow between two types of shell and tube condenser. The reflux condenser will be a 4″ / 1/2″ shell and tube, heavily inspired by the Jackson Crossflow condenser.

The crossflow condenser as it is traditionally configured. This is a type of shell and tube condenser. Image credits to Samohon on homedistiller.org/forum

By mounting this offset instead of overhead, I can form a pool of distillate, which can be drawn off back to the column as reflux, or via a needle valve, as product takeoff via liquid management. This will allow me to bleed the heads components without letting them contaminate my product condenser.

The product condenser will be a 63mm & 13mm  ‘shotgun’ type of shell and tube condenser.

This is a standard configuration for a "shotgun" type shell and tube condenser. Image credits to Samohon on homedistiller.org/forum

If you look at the illustration of my design, you’ll see that the shotgun condenser is designed to be removed, and is also way, way overkill for a reflux product condenser. This is so that it can be reused as the condenser for the pot still.

The reason I’m getting away from liebigs and coils for cooling is simple – backpressure. I recirculate all my cooling water via a pump and a radiator, and the pump really struggles with the coils. shell and tube condensers by nature have a very wide water path, so you can get very good flow rates on a shitty pump.

The pot still head is going to be more simple, I’m not even going to bother drawing it up. a 90 bend at the top of the column, then a triclamp, then a 45, reduced into the shotgun condenser. The triclamp will allow me to set any output height, which is a huge quality of life improver when running a still – remember you can’t use a plastic funnel or anything like that to direct output, not ethanol safe. Here’s a mock up:

Just some parts thrown on the table to illustrate the pot still shape.

Initially, I’ll just be using a keg boiler. Longer term I think I’d like a small hot water cylinder. They’re all copper here, and about a 100-150L boiler with pre-installed elements and drains would be very convenient I think. Either that or I’ll look into getting a stainless boiler fabricated for me, or salvaged.

Hope that clears up what I’m up to.

Cheers.

04
Jun
11

A still is born. Well… Conceived?

Who would trust me with one of these?

I’m finally getting started on my new still.  It’s going to be a modular system that can be reconfigured into various reflux column heights, and the humble pot still. It’s going to be 103mm, 63mm, and 13mm copper pipe, and stainless triclamp ferrules.  No Copper fittings if I can avoid it, although I might end up getting a couple of 4″ endcaps imported from aussie. Why not use copper fittings, I hear you ask? Because in NZ, buying copper fittings is like pulling down your pants and grabbing your ankles. You’re going to get reamed. Even at trade price, 103mm fittings are well over 100 dollars, closer to 200-300 for some of em.

My stash of triclamp unions.

So, this build has to be adaptable, modular, and made entirely from ferrules (I came across a supply of very, very cheap triclamp unions in a fair game of chance) and pipe. How hard can it be right? I’ve never soldered much, especially not with an oxy-acetylene torch, but as an engineer mate of mine said the other day “Yeah bro, people stupider than you use lathes and gas welders every day”.  With that sentiment in mind, I set out on some deep end learning (the best sort of learning).

First challenge – Get the copper pipe to mate nicely and strongly with the stainless triclamp ferrules. The pipe ID (~102mm) is approximately the same as the ferrule ID, but the ferrule has an extra 1-2mm of wall thickness, so the OD is more like 107mm, compared to the pipes 104-105mm. Two clear options – expand the copper over the pipe, or somehow get it fitting on the inside of the ferrule.

Second, related challenge – Make sure that when the ferrules are brazed to the copper, they will be square – this is important, as the even distribution of downwards flowing reflux in a reflux column is a big help for column efficiency, and crooked ferrules lead to leaning columns.

Third challenge – Make bends without buying fittings. This one seems pretty easy. Cut the pipe at precisely 90-desired angle)/2, rotate the two halves 180, then carefully braze them together. Then braze on my triclamp ferrules to each end without completely fucking the joint I’ve already made.

So, Leaving the whole “not paying bullshit prices for fittings” thing for now, I started to sort out that ferrule mating and squaring problem. I actually had a bit of a false start on this one, and built myself a very, very homemade sort of mandrel expander, 4 segments of steel that could sit around a lathe chuck, which you could then wind out to expand the pipe. This did leave challenge three as a complete nightmare though – how could I seat that square for brazing? I didn’t come up with anything, so after wrecking one end of a column section and completely failing, I decided to look at a new method – get the copper inside the ferrule.

I couldn’t think of an easy way to go about contracting the pipe. I calculated the relative coefficients of expansion with heat, and the distance I needed to move them was greater than I could do by freezing the copper and putting the stainless in the oven. The stainless is way, way too hard to think about expanding, even if I could do it even enough to still seal. So, I had to turn to the lathe.

Lathes are pretty cool, especially ones like this with a good autofeed and digital readout.

I ended up turning a wider ID for the ferrule, about 8mm deep into it. I figure that 8mm is enough surface for a good lap joint, plenty of space for the solder to wick down and make it strong. Stainless, especially in grades  like this (316L), is a tricky metal to machine. It’s very hard, kind of stringy, and needs a lot of care when working. Bear in mind when taking anything from the following process that I’m a rank novice at fabricating.

A ferrule during machining

When I set the flange in the chuck, I clean both surfaces, tighten it slightly, and then get a rubber mallet and gently tap all around to make sure it’s sitting square. I set the lathe very slow, 112 RPM seems to be a nice spot for me. I tried 80 and it’s great too, but 112 gets it done quicker without too much extra heating. The auto feed speed is set to about 0.05 mm/rev (not sure on what the correct notation is for that unit? distance travelled per revolution of the workpiece). I’m only cutting about 0.5-0.7mm per pass, so about 5 passes required to turn out the ferrule to fit the pipe. As for cooling, I just stand there with a bottle of cutting fluid and slosh a little bit onto the tool and the workpiece every now and then, once or twice per pass is working really well for me. You can probably see a bit of the fluid pooled on the ferrule in the above photo, a pink liquid. I’ try to tweak the depth / speed / feed until I get a nice spiral swage coming off in long strings, and I pay attention to the colour of it – a pale straw colour is acceptable, this is the point I’m aiming for in terms of efficiency, although sometimes I’m going slower if I’m not paying attention. If you start getting purple, slow down, more fluid, give it a rest, etc. That should be a drama though, because the cutting fluid will be boiling constantly by that stage.

The results sit tight and snug, though the slight deformations of the pipe from cutting can mean that if you want them really snug you need to give the pipe a slight squeeze in the vice or something. After the first one, which I had to seat with a hydraulic press (overkill), most of mine have been fine to seat by hand after I’ve filed a leading edge onto the copper.

Filing a leading edge onto the copper to help it seat in the machined ferrule.

After filing, they came together nicely, square, and almost perfectly flush on the inside:

Nice and flush

Nice and square.

Also appealing about this method is the fact that copper expands faster than stainless when heated – that means these joints will get tighter, not looser, as they are brazed, or as the still is operated.

So, with the ferrule joints no longer a problem, I needed to get started on making some copper bends out of my pipe. Off the shelf bends are normally die-cast – this is way beyond my resources.

A 90 bend being trimmed down to size in the drop bandsaw.

The fittings I’ve needed so far have been pretty easily created by using a drop bandsaw running nice and slow to cut for a brazed miter joint. I could cut at 45 and end up with a 90 bend like pictured being worked on in the drop bandsaw above, or at 22.5 and end up with a piece like below. I actually made that 90 on top of a long section to be the column on my pot still before realising that I’m wasting a potential 30cm of column height on the reflux still by not putting a union in below it – now I’ve cut it I can take that section and pack it. Modular!

A home made 45 bend with a ferrule seated on one end

I still haven’t decided if I’m going to make 4″ endcaps for my shell and tube condenser (reflux condenser for the column), or get someone to buy them for me in aussie and send them over. It seems that their prices probably make it worth it compared to the time cost of more complicated fitting fabrication than simple bends.

As for the actual brazing, I’m still a novice with the torch, but I think the after some TLC with a file and emery cloth, my joints aren’t going to be too ugly. First of all I lightly sand and flux both surfaces, then press fit, then reapply a bit more flux to get it sitting on that lip of the stainless:

well fluxed and seated ferrule

Then I get out the oxy torch and set the flame pretty neutral, maybe a hair on the carburizing side. I heat only the copper side of the joint, and maybe 5cm up from the joint. Copper transfers heat so well that you’ve got to work like this to avoid buggering the stainless. Then it’s just a matter of getting the workpiece up to a flow temperature for my solder rods (silfos 15, got a kilo or two of it for free), and soldering the joint. I try to keep the torch moving across the work so that it doesn’t overheat a specific area too much.

Action!

I’m going to experiment with different ways to “lay” the solder onto the joint, and see if that gets me neater. here is a snap of a joint that I’ve quickly hit with a wire brush. More cleanup to come.

Hot off the press

For now, at least things are finally happening on this build, I’ve been talking about it for almost a year now, it’s good to put solder to copper.

I’ll be doing some more brazing shortly, and then working on my shell and tube condensers. That will probably be my next post. When this is all done, I’ve got a lot of scotch I need to run! I’m filming the whole build, so when I’m done I’ll stitch it up into something entertaining.

Cheers,

Richard




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