For school, we have made a project we think is worth sharing!

Bart is a prototyper and he works in a Industrial Design Center.

Bart is physically disabled, he has only one functional hand, which makes certain actions very hard for him. As a prototyper, fixing a screw for example is almost impossible with one hand. That is why we made a ‘screw help for cordless screwdriver’ so Bart can fix a screw on his own.

Bart can slide the ‘screw help for cordless screwdriver’ very easily over the cordless screwdriver and then he can pull everything very tight with an elastic rope. Then, the screw can be clicked into its place and tightened halfway. Then, Bart has to pull the string in order to turn the screw help down and to go on fixing the screw.

The ‘screw help for cordless screwdriver’ doesn’t hamper. When someone else wants to use the cordless screwdriver, the device doesn’t have to be detached. Moreover, the device is also ideal for people who find it difficult to fix a screw with even two hands in hard-to-reach places. The light and fine design makes the device not heavy at all and very easy to handle.

There are many kinds of cordless screwdriver. That’s why we developed a tool with which you simply have to measure only two sizes. The measurements have to be filled out in the software and the ‘screw help for cordless screwdriver’ can be customized to the cordless screwdriver

The center point where the thermoforming body should come is taken at the height of the handle.

The parameters are taken on variation 1 and variation 2 (see the picture by step 2)

Note: however, we can’t make the screw help for all cordless screwdrivers. Because of the special shapes it is far too complex. Due to the position of the handle we get a product that is out of balance.

Leen & Maiken

CAD Files.zip
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Step 1: What Do You Need?

1. Some basic tools you have at home

2. An aluminium sheet of 2 mm thick. Maximum size 600mm x 450mm

3. A shoelace (minimal elasticity)

4. Elastic rope

5. 8 bolts (4 x 12 mm) and lock nuts

6. Polystyreen sheet (2 mm)

7. Thermophorming machine

8. Lasercutter

9. Siemens NX (software) to use our parametric workdocument

10. Illustrator (software) for making lasercutfiles

11. Semi Gloss Black acryl spray paint

Step 2: Measure

Measuring the cordless screwdriver:
variation 1 and variation 2

Step 3: Enter Dimensions in NX

Open the NX file and type ctrl + e, you will get a pop up file

Enter the dimensions per variation.

Step 4: Lasercut

To make a lasercut document for e.g. a "lasercutter Versa" where the dimensions are maximum 600mm x 450mm, follow these steps:

Open the assembly file in NX and change the correct dimensions with 'ctrl + e' and save. Than open the drawing of your sheet metal and update the file. Now you get the right drawing to lasercut. Export this document as a .dwg-file.

Then open Adobe Illustrator, choose the correct dimensions for your new document and insert the drawing. Ungroup this and remove all unnecessary lines. Group back your drawing and all lines that need to be cut must be in red and 0.025mm thick. The lines that only need to be engraved and therefore only to be bended should be in blue. Here too you choose the line thickness: 0.025 mm.

Step 5: Bending the Aluminium Bars

Bend the 3 pieces as in the drawing. With the engraved lines from the lasercut you can easily bend the bars. If you don’t have any metal bending tools, you can do it with just a vise and a hammer (make sure to protect the metal surface by clamping a piece of wood or rubber between the vise)

Step 6: Coating

Before coating use a metal grinding belt or a file to round the edges of the steel bars, so the user won't hurt himself.

In order to smoothen the aluminium surface smooth you can paint it in any color you wish. A coating is recommended so the surface won’t suffer from any corrosion.

Step 7: Thermoforming

In order to attach the side strips over the cordless screwdriver we make a thermoformed solid. We make this by means of a foam model that then is being thermoformed. We make the foam model with the dimensions at the back of the side strips up to the center point where the variants start.

When you have shaped the foam model well, you can thermoform it with a polystyrene sheet of 2 mm thick. Cut out the shape and shed. Drill 6 holes at the same height of the holes in the side strips at the back.

Step 8: Making the Body

Put the thermoformed solid and the 2 side bars together with 6 bolts and lock nuts. Just like in the pictures 1 & 2..

If you bended the bars in the right way, the front piece should just fit in between the front part of the solid. Use the bolts and lock nuts to attach the parts and make sure the V-gap is on the upper side. Don't tighten them too hard, so the front piece can still move around.

Step 9: Putting the Pieces Together

Put the elastic rope through the middle holes in the middle on each steel bar on the side and make knot just like on the picture. This will help to hold the whole body on in place.

Put the non-elastic cord (shoe lace) through the hole on the front piece and the one hole left on one of the side bars.