How to Build a Larkin Beer Engine
You've probably heard of a beer engine - the traditional English method for serving real ale without pushing with carbon dioxide. What's a "Larkin" beer engine? Watch this video for an introduction:
Unfortunately, the video lacks the level of technical detail I would like to see. So, here is how I built mine.
Why do you want to drink beer? I hop you have that answer. Why would you want to drink "real ale"? That's a personal choice that each beer drinker should make. Best advice: try it and see if you like it.
Putting beer in plastic like this makes it easy to transport with low chance of breakage. Take it camping, fishing, to an outdoor concert...whatever is safe a legal, of course.
You're reusing a bottle that might otherwise go to waste. We craft beer hippies love that.
If you're a brewer, you probably dig building gadgets like this. This build is cheap; $15-$20 in parts and less than an hour to put together. I think the return is well worth it.
- One 1/4" Hose Barb x 1/4" FIP (Part # LFA-197)
- One 1/4" Hose Barb x 1/4" MIP (Part # LFA-192)
- One 1/4" Hose Barb x 3/8" MIP (Part # LFA-193)
- One 3/8" FIP Cap (Part # LFA-769)
- One 1/2" I.D. (#10) O-ring. Technically 11/16" O.D. x 1/2" I.D. x 3/32"
- About 1.5 feet 1/4" I.D. vinyl tubing. I got a 10 foot roll because I know I'll use it.
- Some thread tape. If you build brewing equipment, keep lots around.
- A plastic bottle. I recommend a 1 liter sized bottle, though I suppose a 2 liter would also work. I wouldn't go smaller than 1 liter, though. I used a 1 liter Dasani bottle I picked up at the movie theater the night before.
- A 1/2" drill bit
- A 1/16" drill bit
- A drill. I used a drill press, but that's not necessary.
- Needle nose pliers
- A sharp knife, box knife, utility knife, tubing knife, etc.
If you watched the video, you get the idea. How I did it step by step:
- Drill 9 or so holes in the end of the 3/8" FIP Cap in a square-like pattern with a tiny drill bit. This will be your sparkler tip. I got 9 in there. I don't think the actual number is important so long as you get good flow.
- Slowly drill a hole in the lid of the plastic bottle. I used a 1/2" bit and filed it out till the 1/4" Barb x 1/4" FIP just barely fit through the hole. You want that sucker to be snug.
- Wrap the threads of the 1/4" Barb x 1/4" MIP and 1/4" Barb x 1/4" MIP fittings with thread tape.
- Put an o-ring over the threads of the 1/4" Barb x 1/4" MIP fitting.
- Push the threads of the 1/4" Barb x 1/4" MIP fitting through the hole in the cap from the side that would face the inside of the bottle.
- I put another o-ring over the threads of 1/4" Barb x 1/4" MIP fitting to make sure everything is snug.
- Thread the 1/4" Barb x 1/4" FIP onto the 1/4" Barb x 1/4" MIP fitting.
- Go ahead and thread the 3/8" FIP Cap onto the 1/4" Barb x 3/8" MIP fitting. You're going to want it in a bit.
- Cut yourself a 6"-8" piece of tubing. This will be the tubing that is outside of the bottle. The actual length isn't all that important as long as it works for you. You'll want to be able to get the sparkler near the bottom of a glass.
- Stick your sparkler cap on one end of your tubing, and stick the other end of the tubing onto the barb on the outside of your cap.
- You'll need to use your judgment to cut another piece of tubing that goes in your bottle. This one has to be long enough to reach from the cap to about 1/2"-3/4" or so from the bottom. You want it to be above the yeast cake, but just a bit.
- Stick that piece of tubing onto the hose barb on the inside of the cap
That's basically it for the serving apparatus. I don't know that you can really call it an "engine", but let's be generous.
How to use it
Easy-peasy - as you know if you watched the video. Brew your beer as normal. You can bottle condition in the bottle you'll use the engine in if you like. Obviously, you'd want to keep a cap on the bottle that doesn't have a hole in it. Alternately, you can condition in another vessel (e.g. a keg) and transfer to the bottle before you serve. I'd recommend going that route to reduce yeast pickup in this set up.
Once you've got beer in the bottle, put your cap-engine on it. All it takes to serve is a gentle squeeze. Go easy. Start with the sparkler about 1/2" to 1" off the bottom of your glass, and keep it there until your glass is almost full. Maintain pressure on the bottle while you pull the tubing out of the glass. Unscrew the cap and release pressure on the bottle to let air back and prevent foaming up the beer in the bottle.