Intro: Grape Crusher
I own a house with a 40+ year old concord grape vine that produces more grapes than I know what to do with (they have seeds so I don't end up eating many of them). I also have a cool basement and room for projects, and this year I've decided to try to make wine. Having tried to make jam with the grapes last year, I've already learned that smashing grapes with a potato masher is both time consuming and no fun. It also isn't very effective.
I visited my local brew @ home store and got a quick run through of the process of making wine, and all the basic materials. The store manager estimated that I had over 100lbs of grapes which could produce close to 10 gallons of juice. From what I remember last year, we took about 15 lbs of grapes (stems and all) and got about 1 gallon of juice after 45min of mashing and squeezing through a cheese cloth. If we want to get through all 100lbs....there had to be a more efficient way.
My basic plan was to use a car jack to push a disk into a perforated stock pot, to crush the grapes. In the next few pages you'll see the contraption I came up with.
Step 1: Materials & Tools
I didn't want to spend too much on this grape crusher since I could buy a tried and true one off of ebay for ~$180.
Large stock pot from Goodwill - $15
(2) 2x4s that were laying around - $Free
(2) 14" x 14" pieces of 3/4" plywood that were laying around - $Free
(2) flimsy plastic cutting boards from the kitchen - $Free
3' of quarter round trim - $3
Brad nails - $1
2.5" Lag bolts & washers - $6
2" screws laying around - $Free
Car jack - Borrowed from the car
6mil plastic sheet - $10
Note: I used flimsy cutting boards because they are cheap and I had them. If I had old thick plastic cutting boards laying around I would have used those instead. All I was trying to do was create a barrier between the plywood and the grapes.
Compound miter saw to cut 2x4s
Circular saw to cut the plywood
Jig saw to cut plywood disk
Hammer for the holes in the pot and the brad nails
Sander (if necessary)
Scissors to cut the cutting board
Step 2: Poking Holes
The pot I got from Goodwill need some holes which I thought I was going to have to tediously drill one at a time. It turns out that since its aluminum, I didn't have to do that. All I needed was a hammer and a nail.
Step 3: Plunger/piston Disk
Now that I had a pot and knew its dimensions, I need to create a disk that would fit snugly in the pot and spread out the force of the car jack on the grapes in the pot. I had some old flimsy cutting boards laying around, so I cut one with scissors to fit inside the pot.
I then used that as a template for the plywood disk, which I cut with a jig saw. The disk wasn't perfect, but after a few test fits and sanding it fit nicely. (if you're a perfectionist use a router with a circle cutting jig to cut the disk)
Step 4: Building the Frame
Now that the plunger was created, I needed a sturdy frame for the pot and car jack to sit within. The frame has to contain the force of the jack on the top and the bottom; the force of the jack pushing off the top of the frame and against the pot full of grapes that is supported by the bottom of the frame.
I knew the pot was a little less than 14" in diameter, 10.5" tall, and that the jack's range of movement was between 7.5" and 15". As such the inside of the frame would be 14"x14" and 20" tall to accommodate the jack, plunger disk, pot, and a little bit of fudge room. To support the jack on top I placed a 2x4 cross beam, and on the bottom, a base of plywood.
I cut the plywood to form a base within the frame, and nailed pieces of quarter round trim on 3 sides. If all goes according to plan, when the juice oozes out of the pot, it'll land on the 14x14 cutting board (that is sloped by the quarter round), and run off the base and into a plastic tub.
I cut the 2x4s for the frame to size, pre drilled holes for the lag bolts, and screwed it all together. I used lag bolts where it mattered as I didn't want the weakest part of the frame to be the joints. Even though I don't anticipate needing a bunch of force to crush the grapes, by using a car jack that can lift 1 ton, screws just weren't going to cut it. I also built guides to keep the jack from slipping off the 2x4 on the top, and the disk that will be in the pot.
Step 5: Finished Product
Here you can see the whole contraption.
To use it we'll start with washed & stemmed grapes in the pot, then add the round cutting board, a 3' x 3' 6mil plastic sheet (to create a waterproof barrier between the grapes and the chemical laden plywood), the plywood plunger disk, and then the jack. We'll turn the screw on the jack which will force the jack & plunger disk into the pot, compressing the grapes and letting juice run out of the holes and into the tub. There shouldn't any liquid shooting out of the holes as the jack will move slowly, so the way its set up now should be fine. If things get ugly we can always wrap the inside of the frame with the 6mil plastic to contain the mess.
Theoretically this thing can crush any fruit you'd want. The only limitation is the amount of pressure the frame can handle from the jack. The jack will win if we push it, but I can't foresee any need for that much force, no matter what fruit we're trying to crush.
As much of my design was due to the materials I had at hand, please consider this more of a guide than a step by step plan. Your intended use may also change the design and materials that you choose to use, so have fun with it. (if you decide to take it to the extreme and build a welded steel frame with a hydraulic jack, please send pics and video!)
More pics to follow once we've put the crusher to use.
I'm entering this into the Epilog Challenge, and if I win, I'll use the laser engraver to make custom wine bottle labels.