Building a Wine Press - Safety concerns for force transfer

[purduephotog]

I posted this over at an engineering forum too, but I would love any feedback you can provide.

Good Evening- I've been trying to design a wine press but am concerned I may fail due to my poor design and the relatively extreme forces involved.

Background follows:

To see an example of a type of press I'm considering, please see this:

my press I had intended to place the hydraulic cylinder beneath the compression chamber- eliminating the chance of contamination. Everything else will be hardwood- or possibly (fir, pine) depending on size.

I would like to 'rest' the hydraulic jack on two pieces of angle iron that are then braced with 2x6 or 2x8. They form the floor of the wine press, and might possibly have a small 'filler' board to keep them from shifting. I expect to use several carriage bolts to hold this angle-iron reinforced structure together. I have access to a OxyAcetylene setup but had not intended to use it for this design.

This floor beam would transfer the force to a pair (4x) of vertical beams on either side. A small filler and stop would separate the two vertical beams. As before, a carriage bolt or two would be used to keep the beams in alignment with each other. These could be made out of laminated plywood (3 to 4" thick) or 4" post beams.

The top of the press would have either one, two, or three 2x8 or 2x12's to transfer the force to the follower. Square stock (spaced with holes- I can't recall what it's called) would be set with a pin to allow me to drop the press further and further down as the pomace was drained of juice.

I was thinking of making the follower (the piece that covers the pomace/must) from simple 2x3/4 plywood and a steel cup to help distribute the force.

That's the background. My concerns are bracing the 20 ton jack properly and preventing the entire press from disintegrating. I do not expect to exceed 6 tons of force with this design as that would exceed

100 PSI on the pomace, and I'm told bad things begin to happen to grape seeds around there.

Given that the pot is 12" in diameter and I'd like to upgrade to at least 18" in the future, that requires a minimum floor beam length of

30" + vertical beam thickness, or about 40" total.

How does one go about calculating the yield strength of angle iron in this case- am I over engineering the bottom? Are my concerns justified?

I have been using this as a source of information:

'm afraid to admit it but I'm a ChemEng/Chem, although it's been so long since I took my materials courses that I don't even know where to begin.

Thanks in advance for any insights you may have-

Jason

[Bob AZ]

Thanks in advance for any insights you may have-

Jason

Re: First wine press. Still have your feet?

Bob AZ

[Jim Hall]

You're probably not going to like my advice. I make 30 to 40 gallons of wine every year and like a wood working project I want it to turn out to be the best wine I can make. It's something I share with friends and give away as gifts. There's no way I would make or use a home-made press as you describe. The ones you buy have evolved over centuries and make the process much easier to deal with. I'm sure you can get a used one for less than what you will spend making one. Now if all you want to do is toy around with making wine, then go for it. If it explodes or gets clogged in the middle of the process, no big loss I guess. But if you get serious, you probably won't be happy with your homemade press, especially if you're making red wine from grapes.. Good luck..

[purduephotog]

*cackle*

I'll send you a bottle of Chateau le'Feet. Cheers ;-)

Bob AZ wrote:

[purduephotog]

Jim-

I do appreciate your comments. I've looked and the cheapest press to be had is about 180$ with the most practically sized one for 300$+. And you're right- I do want to futz around building it. Of course, that does mean that I do want to do it right and if this one sounds like it'll fail then I may have to re-examine the priorities. I'm going to be spending about 1000$ on juice and skins this year, or enough to make about 110 gallons before *hic* losses.

Ideally I'd want a stainless steel ratchet press. Cheapest one of those was around 600$.

If you know of or see cheap presses, keep me in mind- I estimate that if I make this all out of 2x8x8 and Fir from HD (sigh) I'm looking at about 100 to 150$ for the size I want, plus the bottle jack.

I wonder how it would make cheese....

If you're near Rochester, swing on up :)

Jason

[todd]

To adequately comment on the design, it would greatly assist me to have a sketch to go with your description. If you want to make one, you can email me or post in a.b.p.w

todd

[RayV]

I have to agree with Jim. The press my MIL has is a monster that takes two guys to lift has cast plates on top and what look like two small pieces of railroad track to cover those plates. As the skins get compressed the ratchet is backed off and 4x4 oak spacers get put in. This thing is all cast iron except for the steel rod in the center and the ratcheting mechanism. Looks similar to this but bigger around:

does also have a homemade press that looks similar to this: it looks as though all of the structural pieces are old growth oak (tough to tell after 40 years of pressing stains). Even with those big timbers it still has iron bars (bolts)across and up & down to keep the thing together. I can't imagine construction grade 2by lumber holding up to the stress you need to put on the skins.

Try getting a used one, neither of hers are available, or build one like the one above out of hefty lumber reinforced with rods.

Don't worry about contamination from the jack, its just a little oil..

[Buddy Matlosz]

I could see needing a press for grapes, but if you already have wine, why would you need a press?

B.

[purduephotog]

Basically, with whites you press the immediately crushed grapes to get 'white' juice. With reds, you let the crushed grapes ferment with the skins intact- the colour comes from the skins.

If you were just to collect the 'free run' red juice after fermentation you'd lose quite a bit. That stuff is expensive- about 1$/lb where

12lbs = 1 gallon.

[Virgle]

basket like used in the old screw presses and use a 30 ton press that i use to press off bearings or whatever. I purchased a hand operated apple grinder and installed an electric motor. The grinder breaks the grapes but doesn't crush the seed. I made 65 gallon of apple juice last year plus my wine.

Virgle

[purduephotog]