Anti-slip bit for slotted headed screws

This is not meant to detract from your beautiful job of documenting that design Ted, but someone beat you to the invention a while ago.

Those are three shrouded slotted bits (medium, large and small) which came with a Black and Decker 3/8" rechargable drill/screwdriver I bought new about twenty years ago. IIRC, it was one of the first battery powered drills available for DIY folks. Its four nicad cells are internal and charged from a wall wart through a cord and male mini phono plug which plugs into a jack on the side of the drill. You read me right, a hot MALE phono plug. If you let it touch something metal the wrong way you short out whatever current the wall wart can put out.

The shrouds on those bits are spring loaded too, but the springs are hidden inside them. It looks like they were assembled and then the back ends of the shrouds spun in a bit to keep the springs from pushing them all the way off the bits.

I bet it would be easier and more fun for most of the guys here to follow your design and make their own than to hunt around to see if they're still being sold. Not many things are put together with slotted fasteners anymore, except when its done to maintain traditional appearances, so It wouldn't suprise me if no one is making those gadgets comercially anymore.

Happy Holidays,

Jeff

Great little tool. The most important part is the actual driver bit. Most flat screw driver tips are designed incorrectly - they are wedge shaped which is good only as a pry bar, not as a screw driver. If the tip faces have parallel sides it will not cam out of the screw slot. But the bit also has to fit the slot width AND length too. It's a little annoying, but every size screw has it's own size driver bit. If you use the wrong one it will cam out the slot. But, if you use the correct driver bits you might enjoy installing slotted screws.

WL Fuller Company makes a great driver bit. See page 93 of their online catalog:

Eide

The set I have (assorted driver tips) has the same sort of three and I've had mine about 4 or so years. I think it was sold under the name of "Snappy". I have used the slotted ones only a few times in that period. ...lew...

And, at the risk of being flamed for repeating this once too often, a gunsmith tought me many lears ago that when dressing a slot screwdriver tip it really helps to grind or file "crosswise", i.e. perpendicular to the axis of the screwdriver, and don't ever "polish" it smooth. Theose sideways cratches dig in help hold the tip in the slot.

He also explained why it's easier to bust loose a tight screw with a long bladed screwdriver than a short one, even if the handles are the same size. It's because we unconciously tend to tilt the blade off axis and pull on the handle like a "crank" in an effort to develop more torque. A longer blade gives a larger lever arm for the same amount of tilt, ergo less chance of your tilting it so much that the blade cams out of the slot.

Happy Holidays,

Jeff

For hand screwdrivers, hollow ground tips the correct size only put pressure at the bottom of the slot. Check out Brownell's for multiple options. SOP for gunsmithing, as buggered screw slots especially ugly on firearms.

Pete Keillor

I have a cheap set of bits like that, but the sleeves on mine are made of plastic. The inside of the sleeve is tapered. They're pretty much useless, the bits slip right off of the screw heads. Guess that's why they were cheap.

The OP, Ted, did a nice job on the tool he made.

-Ron

Thanks, Jeff. I do not claim to have invented this device. In fact, I have had several commercial ones rather similar to yours but probably not as good quality. I even had one with the shroud made of plastic that wobbled so badly that it snagged and disintigrated. I had given up on them but since I still had quite a few perfectly good slotted head screws, I decided to have a go at making a better mouse trap.

Thanks for the pix.

Mine has an unusually long portion tracking on the bit. Makes it more stable.

Thankfully!

You too. Three candles tonight?

Ted

Neat! Others have noted that such things are available, but I'll bet you had it made and were driving screws in less time than it would take to find and buy one.

An additional trick I've used is to gritblast the tips of driver bits with silicon carbide grit. Gives 'em some tooth.