The Armful Dish
This special dish enables you to easily cut your food one-handedly
This useful tool consists in a square box, on the top of which is placed a dish (you can use whatever dish you want, because TÅD was created in order to suit standard size dishes) containing the food you have to cut. Then it holds the food, thanks to its system of small bended manually-adjustable plexiglass bars, and you can easily cut your food by just using one hand
- Wood panels (thickness: 6 mm)
- Wood glue 4 bolts (60 mm in length, 6 mm in thickness without taking into account the “heads” of the bolts)
- 4 bolts (25 mm in length, 5 mm in thickness without taking into account the “heads” of the bolts)
- 4 nuts (internal diameter: 6 mm)
- 4 nuts (internal diameter: 5 mm)
- 8 hooks
- 4 rubber bands
- 4 washers (internal diameter: 6 mm, thickness: 1 mm)
- 4 washers (internal diameter: 6 mm, thickness: 0,7 mm)
- Plexiglas (thickness: 3,2 mm)
- 2 rubber sheets ((at least) 300 mm x 300 mm each)
- Quick setting glue
- Adhesive tape
- Laser cutter
- File/belt grinder
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Step 1: Designing on Inkscape
Here we go:
Here follows the link for the already designed box, but if you want to create it completely yourself you’ll be provided with all the dimensions of all the pieces you need in the following Step.
Step 2: Cut All the Cuttable Stuff
Set your laser cutter values before starting (and make sure the laser ray doesn’t go out of focus):
Wood and Plexiglas
- Speed: 25 mm per second
- Acceleration: 2500 mm per second
- Power: 40% minimum/100% maximum
Cut a tabbed box (leave the edges of one side untabbed, for you’re going to create at an easily removable lid that is going to slide freely through the opening of the box, and it’s easier to do that if your edges are straight and smooth). Laser-cut 4 holes in the sides of the box, in order to allow the positioning of the Plexiglas bars linchpins.
Cut 4 parallelepipeds, you’re gonna use them as supports for the covering wood panel of the box.
Cut 8 trapezoidal supports, with a square angle at the base and a hole in the middle.
Cut 4 parallelepipeds (you’re gonna have to erode and refine them with the file later on, and shape them into trapezoids).
Cut 4 little supports with wood thickness of 6 mm: you’ll need them as separators, and they are to be inserted between a couple of square-angled trapezoidal supports.
Cut the covering panel in the shape of an octagon, in order to leave the angles of the box uncovered and open.
Cut the bended plexiglass bars, you’ll need them as “hooks” in order to hold in place the food while you cut it.
(All precise sizes appended at end of Step 1, in other words here:
- Upper panel (octagonal): length from side to opposite side: 300 mm; longest side length: 140 mm; shortest side length: 98 mm
- Lower panel: square-shaped, 300 mm x 300 mm (tabs included)
- Side panel: length (tabs included: 292 mm; tabs excluded: 286 mm; thickness: 6 mm; height (tabs included: 55 mm; tabs excluded: 49 mm)
- Squared-angle trapezoidal supports: height: 44 mm; longest side length: 30 mm; shortest side length: 15 mm; distance of the hole from straight side: 7 mm; distance of the hole from base: 17 mm; diameter of the hole: 5 mm
- Parallelepipedal supports to be shaped into trapezoids: longest side length: 30 mm; shortest side length: 20 mm; angle of inclination (rake angle) between inclined sides and base: 45°
- Upper panel supports: base length: 30 mm; height 44 mm; thickness: 6 mm)
- Separators of squared-angle trapezoidal supports: thickness: 6 mm; height: 5 mm; length 40 mm
- Plexiglass bended bars: longer arm length: 130 mm (angle included); shorter arm length 120 mm (angle included); thickness: 6 mm; arm width: 9,5 mm
- Holes in the sides of the box: width: 25 mm; height: 15 mm; distance from edge of lateral side: 35 mm; distance from edge of upper side: 23 mm.)
Step 3: Assemble the Panels
Time to use the wood glue and some tetris skills: assemble the panels wedging them in one another, putting glue between the tabs in order to interlock the panels more tightly and sturdily. Put the glue in thin layers, endurance of the joint will increase. Make sure to press the panels against one another so that they’ll stick together. At the end of the process you’ll find yourself with a square box showing 4 smooth edges on top. Glue the parallelepipedal supports for the covering panel to the internal sides of the lateral panels, right in the middle of every panel. They’ll support the covering octagonal panel once positioned.
(Once you’ve assembled all the wooden parts, we suggest laying a coat of waterproof paint on the box, to make sure no liquid ever comes in contact with the wooden surfaces.)
Step 4: Erode and Define the Trapezoidal Supports for the Bolts
Erode the shortest sides of the little parallelepipeds (30 mm x 20 mm x 6 mm) that you are going to use as supports for the nuts of the bolts (the ones you will employ to hold down the Plexiglas bars once in position, when holding the food) with an angle width of 45°. Erode the wooden parallelepipeds using the belt grinder. At the end of the process, you’ll obtain 4 trapezoidal supports ready to be glued in the angles of the box, at a distance of 6 mm from the upper edge of the box. These supports will create space for the bolt nut.
Step 5: Create Internal Double Squared-angle Trapezoidal Supports for the Linchpins and the Bended Plexiglas Bars
Glue the separators in the middle of two squared-angle trapezoidal supports, just at their base, in order to create a stable structure in which you can place the linchpin bolts with the moving bended Plexiglas bars.
Step 6: Round the Edge of the Shortest Arm of the Plexiglas Bars and Carve a Hole in It
Round the extremity of the shortest arm of the Plexiglas bars by means of the nippers, and then refine the edge using belt grinder and file.
Now drill a hole for the linchpin to go in, right in the middle of the extremity we’ve just taken into account (in other words, the shortest). Now your bars are ready to be assembled.
Step 7: Here Comes the Delicate Work (involves Drill; Diameter of Drill Pit: 6 Mm)
Drill the lateral edges of the box (the ones belonging to the wedged panels that form the angles containing the wooden parts assembled and glued in the preceding Steps). Make sure you’re drilling the hole forming an angle of 135° on your left and on your right with each side of the box (the two sides forming the angle that contains the glued parts mentioned before). Once you’ve managed to make a hole in the edge, take a deep breath and start drilling the wooden trapezoidal support (the one with two 45° angles at the base) right in front of the drill pit. Repeat the action for all other lateral edges, then add a bolt nut behind the trapezoidal support, between the angle and the support itself, using the pliers. Now you’re ready to insert the 60 mm bolt in both the hole in the edge and the hole in the support. The nut will allow the bolt to tighten.
Step 8: Glue the Structures You Obtained in Step 4 in the Angle of the Box
After gluing and pressing the three pieces together, place the structures right in front of the trapezoidal supports you glued to the box (and drilled) before, and glue the side that contains the right angle of the structures to the trapezoid support. You’ll see the side containing the right angle facing the angle formed by the panels of the box wedged in one another. Also put some glue under the base of the structures in order to make them stick more sturdily to the box.
Step 9: Insert Linchpins, Washers and Plexiglas Bars
Insert the linchpins in the holes carved in the lateral panels of the box, then in one of the holes of the squared-angle trapezoidal supports, then insert every linchpin in a washer of whichever diameter you want (though, of course, you only have two options: 1 mm or 0,7 mm in thickness), then insert them in the bended Plexiglas bars you drilled in Step 5, then insert them in another washer of different diameter (of course you’ll have to choose the option you rejected before), insert now the linchpins in the remaining hole of every squared-angle trapezoidal support, add the bolt nut on top of the bolt (that has been called linchpin throughout the whole Step 8) and tighten. The mechanism that allows motion of the bars is now almost ready. Almost.
Step 10: Glue the Rubber Sheets to the Upper and Lower Panels
There’s not that much more to add, just take the quick setting glue and stick the sheets to their respective panels, but first cut them as requested (they’ll have to be shaped just like the panels they’ll be glued to).
Step 11: Insert the Hooks
The hooks we’re going to use have a threaded shank, so as to be easily inserted in the angles of the box, just at the base, near the angles, by means of a screwdriver.
Step 12: Add Rubber Bands
Insert the Plexiglas bars in the rubber bands, make the bands slide until they reach the middle of the shortest arm of the Plexiglas bar (the one inserted in the mechanism) and secure them to the hooks the hooks you inserted in the preceding Step. The rubber bands will hold in tension the Plexiglas bars: when in their natural position, the shortest arm (the one inserted in the mechanism) will be perpendicular to the ground while the longest will be parallel to the ground. Tightening the bolts you’ll be able to lower the Plexiglas bars.
Step 13: Put Adhesive Tape for a Comfortable Grip
Put some adhesive tape on the heads of the bolts you are going to use to lower the Plexiglas bars in order to make the grip more comfortable; otherwise you may find it difficult to grip the head nice and tight while rotating the bolt.
(Adhesive tape is already visible in the picture above, it’s the green thing sticked on the head of the bolt)
TAD, The Armful Dish, is now ready-to-use!
(Click here to watch a video of TAD in action)
Made by Arianna Bernardi, Andrea Ciusani, Erika Marchioni, Margherita Pirovano e Emirand Ranzi, 4ªE Liceo Scientifico Luigi Cremona, Milano. Project realized during the stage at WeMake (https://www.instructables.com/member/WeMakeMilano/)
Participated in the
First Time Author Contest 2018