Some folks up in our old neighborhood have taken up the homebrew cider equipment torch, and produced a very attractive hydraulic tie-bar press made of hickory:
They then proceeded to make two bins(!) worth of cider using a hand-crank grinder – that is serious work! These folks obviously have the skills to build stuff, so I would imagine they’re thinking about new grinding equipment for next year.
They were powering the hydraulic press From a small tractor, and from their blog entry it sounds like they had some trouble with the fabric, and with the racks they used. I’m just speculating, but I suspect that these could be related. They started out using canvas, which sounds like it blew out, so then they switched to jersey (which is much weaker I think) – maybe they can clarify in the comments. Based on our experience, canvas should work OK if you’re careful. We use the heaviest muslin we could buy at the fabric store in West Lebanon, just north of I89 – it sounds like that same fabric store was flooded out by Irene. I think the material is sometimes called ‘drill’, but it feels just like a fine canvas. It occurs to me that Home Despot used to sell natural canvas drop cloths that might do in a pinch, though I doubt the material is very good quality, and I’d wash it a couple times in hot water, since it’s surely not food grade.
Anyway, even with the heaviest cotton fabric we could find, we have had blowouts when we applied pressure too quickly. The trick is to bring the ram down VERY slowly once the pressure starts to build. The hydraulic presses are capable of delivering between 50 and 100 PSI to the stack itself, and if the pomace is still liquid-y when you get up to pressure, or if the radius of curvature of the fabric isn’t good and tight, it will burst right through. This makes perfect sense from a mechanical engineering perspective in terms of hoop stress in pressure vessels, but it makes intuitive sense once you’ve seen the pomace streaming out through a bulging hernia in the fabric. You need to gradually ramp up the pressure so the partially-exhausted pomace helps form bridges between the gaps in the grates; then you can really hit it with pressure – we go up to ~2500psi on the 4″ cylinder, but not until the stack is nicely consolidated. Even then, our fabric has been in use several years and we’ve had a few ruptures, so now we use 2 layers just to be safe – the yield is not noticeably affected.
It sounds like the Lockehaven folks are going to try making grates with 1/4″ plastic next year; I would caution that the fabric is pretty good at poofing out and filling shallow gaps. Our grates are made of 3/4″ by 1.375″ slats with gaps about 5/8″ wide between them, and I wouldn’t want much less than the 3/4″ for cider to flow through. Some of our grates are made of basswood (much softer than hard maple) and others are red maple (also somewhat softer) and we’ve used them a few years now, so I suspect the issues they were having might have been related to too much speed.
Anyway, I’m glad to see other folks home-building serious cider equipment – nice work, guys!
PS. it looked like they might have been aiming to ferment some of the mac/cortland cider. I suspect that a lot of folks get into the situation where they want to make hard cider but can’t get decent tart or bittersweet apples. We had the issue last year where we bought a bin of Dabinet from Poverty Lane, but we couldn’t get any tart apples (due to the widespread frost), so we ended up with several tanks of seriously unbalanced cider. Steve Wood would probably swoon if he heard we were adulterating our brew, but Holly discovered that 3g of malic acid from the brew store took our cider from way-overbitter to pleasantly tart. 1.5g per liter was more to my taste, so that’s how we bottled some of our 2010 stuff. Better Living Through Chemistry, as Jillian Cooke would say – not everybody has the luxury of 100 acres of fruit to pick from in blending their cider. This year, Steve couldn’t sell us any bittersweets – the brew store also sells tannin; we haven’t tried that though.