This Instructable was inspired by the Universal Nut Sheller invented by Jock Brandis of the Full Belly Project. The original design can be found here.
8 bolts - I used 6 one and one half inch and 2 two inch bolts. You'll need the nuts also.
Various washers. At least 3 for the rotor.
1 threaded rod (1/2 inch x 24 inches)
1 angle iron (36 inches)
2 two inch threaded iron pipe (3/4 inch)
4 threaded PVC pipe (1/2 inch)
1 2 x 2 foot blue 1/2 inch insulation board
2 plastic waste paper baskets (found at Walmart or most other home supply stores.
2 forty pound bags of sand mix concrete
Duct tape (masking worked also)
Bucket or plastic bin to mix concrete
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Step 1: Preparing the Forms and Blue Board.
1. Place the blue board on a flat working surface and get out your marker.
2. Put the larger stator mold top down in the center of the blue board.
3. With your marker, draw a line around the edge of the stator.
4. Take the rotor form and center it within the first circle. Draw a line around it.
5. Take a razor knife and carve a groove just to the inside of each circle. 1/4 inch wide and 1/4 inch deep will be fine. This will hold the forms in place while pouring the concrete.
6. Again with your marker, mark six evenly spaced dots within the area you have created between the circles. This will serve as a guide for the placement of the bolts.
7. Cut the bottom out of the larger stator form.
8. Cut the form down the side from top to bottom. This allows for and easier release for the set concrete.
9.. Drill a 1/2 inch hole in the center of the bottom of the smaller rotor form.
10. Cut the sides of the rotor forms 3/4 of the way down from the top. Make the cuts directly across from each other. This allows it to release from the set concrete.
Step 2: Dry Fitting the Forms
1. Take the 1 and 1/2 inch bolts and gently push them into the six marked locations within the circle.
2. Place the smaller rotor form in its groove.
3. Place the larger stator form in its groove.
Step 3: Making the Machine (Stator)
I have not spent much time going over the hardware for the project. The PDFs can be downloaded herehere. You will see that the hardware I use has only been slightly modified to fit the measurements of this machine.
1. Move the blue board and forms to a level surface. You'll need somewhere that you won't mind getting a little concrete and water on. I used the driveway.
2. Mix the concrete. A helper is always nice!
3. Weigh down the outer stator form and start filling it up. Tap the sides as you go to settle the concrete and move any air bubbles to the surface.
4. After the form has been filled, gently push the two remaining bolts into the concrete opposite of each other.
Step 4: Making the Machine (rotor)
1. Take the rotor form and place it on top of some thing that will allow for the rotor shaft to pass through the 1/2 inch hole. It must also be high enough for the shaft to be centered vertically inside the form. I used a concrete block.
2. After placing the shaft into the form, pour six inches of concrete tapping constantly to remove air bubbles.
3. Center the shaft in the form. Any circular flat item can be used. Drill a 1/2 inch hole in the middle and slide it over the rotor shaft and into the form. It should touch the outer edges of the form. Take measurements from the shaft to the outer edge to make adjustments to ensure that the rotor will spin true.
Step 5: Assembly
Sorry but I don't have any pictures of the actual assembly.
1. Remove the stator from the form before it has completely dried. Roughen the inner stator by scrubbing it with a wire brush.
2. Remove the rotor from the form and roughen it also.
3. Install the rotor into the stator using the metal hardware described in the Full Belly Project PDFs.
4. Cut the 36 inch angle iron in half and use your angle grinder to cut grooves to fit lower bolts. Secure both sides with washers and nuts.
5. Attach your handle and shell away.
I have shelled both pecans and peanuts with this sheller. It is amazing. Definitely a project worth supporting.