D4E1 Screw Help for Cordless Screwdriver

For school, we were given an interesting project we think is worth sharing!

The problem:

Bart is a very creative prototyper and loves to make stuff. Bart has only one functional hand, therefore very simple actions can be exceptionally time-consuming. For example fixing screws isn't easy with one hand, especially when the screw isn't magnetic. The screw doesn't hold on to the bit and falls off before it can reach the surface.

The solution:

We made a tool that fits on many types of cordless screwdrivers. With this extension you can "lock" the screw on the bit and "unlock" it when you're halfway through driving it in the surface. Bart can easily fit the extension on his screwdriver by himself. Once he makes sure it's fixed in position, he can use it untill he decides to take it off again.

With this solutione, we can hopefully help a lot of other people with the same problem.

Céline Bruyneel, Natan Doms and Claire Vandenameele

• Some basic tools you have at home
• A steel flat bar (20mm wide, 4mm thick) and an aluminium flat bar (20mm wide, 2 mm thick)
• A shoelace (minimal elasticity)
• Elastic rope
• 2 rivets (diameter 3mm, length 5-8mm) and a rivet gun/machine
• Rubber sheet (1mm thick)
• Double sided velcro (20mm wide)
• 2 bolts (3 x 12 mm) and lock nuts

• Use a hacksaw to cut 2 pieces of the steel bar, each 20cm long.
• Bend the 2 pieces like in the drawing. If you haven't 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)
• Saw a piece of the aluminium bar (15cm)
• Bend this part with bending rolls in an arc of 180 degrees ( diameter about 7 cm) and then bend the edges to the outside by clamping the piece in a vise and hammering the ends around the steel bars. This step will be difficult to do without a bending tool, but it doesn't have to be an perfect arc to work.

• Drill 2 holes (Ø 3mm) in the aluminium bar, one on each side of the arc.
• Drill in one steel bar 3 holes (Ø 3mm). Two holes about 2 cm next to each other, just behind the middle of the bar. And one hole 1 cm from the front side of the bar.
• Drill in the other steel bar 4 holes (Ø 3mm) , three holes identical to the first bar, and the third hole 1.5 cm in front of the other two holes in the middle.

• Optional: mill a gap (2 mm deep, 2cm long) on the end of the 2 steel bars. This is to make sure that the velcro will stay in place.
• Use a metal grinding belt or file to round the edges of the steel bars, so the user won't hurt himself.
• Before you put together the bars, make sure you have done all the steps before right. Once they are riveted, it will be harder to change something.
• Use a rivet gun/machine to put the aluminium arc and the 2 steel bars together. Just like in the picture. Make sure that the bar with 4 holes is on the left side of the arc (or on the right side if the person who will use it is right handed)

• Cut another piece from the steel bar (15 cm long)
• Bend the piece like in the picture, again you can use a bending tool or just a vise and a hammer.
• Drill 4 holes (Ø 3mm) in it. One in the middle, one on each bended side and one on the left side (right side if the person who will use it is right handed).
• Use a hacksaw to cut out a V-form in the middle, just until you reach the hole in the middle.
• Make the middle hole conic by drilling a little with a bigger diameter drill.
• Chamfer the edges with a small flat metal file.
• Use some sandpaper to make it smoother

To make the steel surface smooth you can sandblast it. Afterwards, you can dye it in any color you wish. A metal coating is recommended so the surface won't rust.

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

• To protect the drill/driver its best to glue a piece of rubber sheet on the inside of the aluminium arc. The best way is to use epoxy glue, fitted to glue different types of materials together.
• Put the elastic cord through the middle holes on each steel bar on the side. And make knot just like on the picture. This wil help to hold the hole body on place.
• Now, put the non-elastic cord (shoe lace) through the hole on the front piece and the one hole left on one of the steel bars.
• Make a little loop on one side of the velcro and sew it together.
• Cut the velcro in two at the right place (cut should come over the second bar when tightened around screwdriver, see picture) and sew it inverse back together.
• Put one end of the bar through the loop. Now, when you put the body on a drill/driver, you can tighten it up with the velcro like in the picture.

Put your driver-extension you made on any drill/driver you like and use it!

This tool can be used with many different brands of screwdrivers (different sizes and shapes) due to the elasticity of the alumium arc and the tensioning of the velcro strips.