homemade wine press

The problem with making your own press in the manner of the basket presses is buying and installing the central metal screw.
Someone (Joe?) posted a technique for pressing with 3 pails and that seems like an idea to consider. I was thinking that a lever with weights at the end might be a good as well and more in the traditional basket press style. Something like this:
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Anyone know how much pressure a standard basket press exerts?

I run my bladder press at about 3 Bar, which is closer to 50 PSI. You need a hydraulic ram or a screw device with a _long_ handle to achieve that kind of pressure over a large platen. A simple lever arrangement won't cut it.

Yes, but remember that psi = pounds per square inch. You have to multiply the 30 by the number of square inches of plate.

Building something like this from scratch isn't easy or cheap. That's why I suggested renting or buying a press. You could always sell it if you decide winemaking isn't for you.

The one in Tuscany was different. The weight of the beam provided the pressure. The capstan screw lowered the beam and thus controlled the pressure

There's many a house "in the old neighborhood" that has just such an arrangement in the cellar. It works perfectly well, is simple and cheap to boot.

Consider using a hydraulic jack rather than a scissor jack. With a scissor jack you apply force in a circular manner, across your wobbly braces, but a little pump hydraulic jack lets you push up & down along the braces. It should be a lot easier & safer.

Also, consider using a board & bungee straps to hold the jack up toward the joist. I would anchor the upper brace to the joist as well.

I built an 18" diameter press from Maple and it is beautiful and works like a charm, however I am not sure I actually saved any money! (materials were close to $500). That hard eastern maple is really expensive, especially where you need 4 x 6 beams. I used an 8000 lb capacity tongue jack to provide the pressure, which gives me roughly 28 psi on the follower. I had a machine shop drill, roll and weld two hoops and I cut, beveled, sanded , drilled, and epoxied each slat before bolting it in. It sounds like, and is, a lot of work. Suggest buying ready made unless you like doing that sort of thing! The tongue jack works great as you don't have to use a lot of blocks etc. You just pull a pin, drop the foot to the follower, and slowly start pushing it down. I use a large mesh bag, but may make a bag out of the poly screen they use for screen doors. I can press a 40 gallon batch of red in 2 loads, and press the skins as dry as I will ever want them. With a larger bag I can probably do it in one load. It works great!
(If you make it beautiful it will raise your stock with womenfolk as well, may offset some of the cost)

Silly me. I should have caught that because the units wouldn't have come out in square inches, didn't do as
I was taught.... don't tell Mrs. Gilljie.

Correct on all accounts.

One thing bothers me though, on the one had we talk about hand squeezing grapes or using a 3 pail system with one pail being filled with 70 pds of water, but when it comes to a press nothing less than a billion pounds per square inch will do? Seems on the one hand the good enough will do but on the other it has to be perfect??

Don, I saw ,in Tuscany, an ancient press like your sketch that used a massive oak beam ~25 ft long. But it used a large wooden screw under the
"free" end to regulate the rate of applying pressure. There was a large capstan like device to turn the screw.

Not a good idea. The grapes at the bottom of the 4 ft press will hardly be affected.

I too have seen one like you describe, it was from Austria... the tour guide said that men or oxen would turn the screw to apply pressure.

So if I was to use a 8' 2x4 and put the platen post at the 2' mark I would have an AB of 2 and an AC of 8'.
The multiplier would then be AC/AB = 8/2 = 4 ?

What's the ratio of movement of point B in relation to point C - if I move C a distance of 2', how far does B move?

Also, is 30 psi the desired pressure would 20/15 or some other number do?

I'm beginning to agree with Tom as well. I'd prefer to save the $250 Cdn but it's the time that's the killer.

So I worked out a test case. A 12" dia basket would work

pi X d = 3.14 X 12 = 37.68 sq in

at 30 psi we get:

30 X 37.68 = 1130.4 pds

If we get a multiplier of 4 by using an 8'x2"x4" with the platen at 2':

1130.4/4 = 282.6 pds

Which is doable especially if you plan to add your own weight by stepping onto the end somehow. If we calculate at 20 psi then it gets even better:

20 X 37.68 / 4 = 188.4 pds

This is really theoretical at this point, I'm going to keep my eye open for a used press.

Are your sure about the calculation where you arrive at 2300 pounds? Wouldn't I only have to think about the 30 psi and ensure
I get that pressure on my round (or square) pressing plate?

Actually that does sound about right if you think about a 1 foot square plate. That would be 144 sq inches, times 30 psi for 4320 pds.
Both numbers just seem like alot more weight then I thought it would need. Even with the 3:1 multiplier that would be 767 pds in your case and 1440 pds for my mine.

Is the 3:1 ratio set by the distance from the start of the cross beam to the down tube and from the down tube to where the weight is suspended, B/A in the below:

I was considering a single 2x4 for the cross beam but perhaps two would be better, something like this when viewed

I know that a hydraulic bladder press operates at about 30psi, so if you have a 10" diameter basket, that's about 78 sq in. Times 30, that's over 2300 lbs of weight on a one-to-one lever system. Note that as drawn your press has an effort arm (pivot to weight) about three times the length of the resistance arm (pivot to basket). This gives you a mechanical advantage of 3:1, so you would only need 1/3 the weight calculated. With a long enough lever arm, you could probably get the weight down to something manageable, but be sure to build stoutly.

I actually know of an antique press of this design, probably from the
1800's. At a farm museum kinda place in Beemerville, NJ. It had a basket dia. of maybe 8", so it would need only about 2/3 the weight mentioned above. It had its two back legs close together with the lever pivoting between their top ends, and I think there was some kind of simple rope turnbuckle to pull down on the far end of the lever. Perhaps a small hydraulic jack could be used to push _down_ on the lever from above?

It's a little hard to see but the jack _is_ underneath. If you look closely you can see the jack handle protruding in the second and third photos. HTH

There are other hydraulic jacks out there with longer motion.
I saw on e-bay the other day some 8 ton jacks with 18.5 in range.

The pressure required goes up as the square of the radius. A 12" tube is to a 24" tube as 36 is to 144, or 4 times the area. To put 30 psi on a 24" circle takes 12,667 lbs of pressure, whereas you can get the same psi on your follower with only 3167 lbs if you stick to 12". The 18" diameter takes
7634 lbs of push to get 30 psi. on the follower. This works nice with a heavy trailer tongue jack, which will give you 8000 lbs of push, and they are pretty cheap (50 bucks?), and quite durable. You need to weld some strong brackets to attach it to the cross arm of the press, but thats just a few bucks.

One benefit of building something like that is if you get into cheese making, you can use a piece of 12" pvc in place of the basket, with a perforated board underneath to make a real nice cheese press for big 25 lb wheels of cheddar or gouda, which age the best. You can't buy that extra aged, raw milk cheese in the stores, and its perfectly safe after only 3 months age. After a year it is outa site! (Have tasted it and am in process of making some!)(I had no difficulty trading wine for 2 minute old, warm, fresh, jersey milk)

To decrease the serface area by half, you would need a diameter of just shy of 17".

email: dallyn_spam at yahoo dot com please respond in this forum so others can share your wisdom as well!

Wups! Area = (radius)² x 3.14 = 36 x 3.14 = 113 sq in (You calculated the circumference.)

No, it's still 565 lbs. You'd still need whatever you weigh plus ~400 pounds.

That's the right idea IMO. BTW, a little bigger than you think you need is better. Plan ahead.

So the options are to increase the leverage or decrease the size of the plate (platen?). In order to get the same volume in the press you could switch from a 24" diameter tube that is 2' high to a 12" tube 4' high.

It all comes down to what losses you are willing to tolerate and how much manual labor you are willing to invest. As I said, for a small batch, you could do the entire lot by hand.

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http://www.geocities.com/mipeman/photos.html

Some very nice photos of other processes here as well. HTH

Another idea dawned on me while considering that the problem in the lever style is the weight on the end. Instead of the lever, I could use a car jack and the weight of my house.

Since I will be working in my basement, I could use a sissor type jack within a two piece pillar above the platen/press:

The ratio of movement will be the inverse of the mechanical advantage.
In other words, if the force on B is 4 times the force (weight) on C, then it travel 1/4 as far as C. That's 'cause you don't get something for nothing in this universe. The basic rule is: Force ( X Distance ( = Force (C) X Distance (C).

Good question. I never really knew the pressure I was applying with a screw press, but my bladder press has a pressure relief valve which is set at 3 ATM, or 45 psi. I think this is what Tom said he runs his up to. The instructions for mine say to operate at about 30psi, but when I ran the bladder press at a small commercial winery, we went to about 2.5
ATM, or 38psi. It's also a matter of personal preference, and how hard you're willing to squeeze the must. Basically, the harder you squeeze, the more wine you get, but at some point the quality starts to suffer.
Wines can be "overpressed", but the greatest drawback to underpressing is probably low yield. I think 15psi is unreasonably low, probably 20psi too. Especially for whites.

You didn't work the numbers on that. Halving the diameter and doubling the length yields a volume that is _half_ what you started with. Using your example, you'd have to increase the height to 8' to retain the same volume.

Nice setup. I think it would make more sense to have the jack underneath and have a solid 4x4 attached directly to the platen. That setup has just got to be dirt simple.
A drilled square basket made from 12" or larger boards, the juice catcher, the hydraulic jack and the platen/pillar setup. I just checked the price at an online auto parts place and a 2 ton hydraulic jack is $20 Cdn.

Trouble is that a hydraulic jack doesn't have anywhere near the range of motion of a sissor jack. If placed underneath the sissor jack wouldn't have a wobble problem either.

I'm going to consider this for next fall.

Thanks to everyone that gave me feedback. I think I have what can be a working design. Now I just need the time to build it. Like they say, work is the curse of the drinking class.