DIY Self-tapping Screw

by Toolify

15K8713

Intro: DIY Self-tapping Screw

Here's a wacky idea: let's try to use a Dremel grinding disc to cut a notch in a screw, and make a DIY self-tapping screw!

STEP 1: Looking at Screws

The difference between a regular screw and a self tapping screw is in the tip. The self-tapping kind has a notch that cuts out some material and allows it to engage in material with less effort.

STEP 2: Grinding

With a Dremel grinding disc, it's easy to create the notch on a regular screw. Thus making the DIY self-tapping screw.

Proof of concept: check! Although, a freehand grinding approach is not ideal.

STEP 3: The Jig

A block like this would be great to hold the tool, and guide the screw into the grinding disc.

STEP 4: Drilling

Hole for the Dremel tool.

STEP 5: Marking

Locating the hole for guiding the screw. Use the Dremel to mark expected depth of the grinding disc.

STEP 6: More Marking

Then use a square to mark the expected edge of the grinding disc.

STEP 7: More Drilling

This hole will guide the screw.

STEP 8: Expected Result

With the Dremel set up inside the jig, this is what should be seen looking through the screw guide hole. The grinding disc is visible in one quadrant.

STEP 9: Using the Jig

Making self-tapping screws with a Dremel is much more precise now.

STEP 10: Performance Test

As expected, the self-tapping screw requires noticeably less pressure to engage.

STEP 11: Don't Breathe This

Screw smoke... don't breathe this!

HIGH FIVE for reading :)

10 Comments

manxm 7 years ago

The type-17 slot is self-drilling the pilot hole for the threads. The threads are helped for be cut by the type-17 point, and the treads also thread form (push the fibres into shape).

jukees 7 years ago

very nice instructable. 5/5

blue LED 7 years ago

Depending on the availability of self tapping screws in your location, this could be a master stroke. Very well thought out and presented Instructable

TheCommander 7 years ago

Also you measured the effectivness of self tapping screws with downward pressure but isn't the main benefit the reduction in horizontal pressure and thus reducing the chances of the wood splitting?

elvisisdead 7 years ago

The main benefit in a self-tapping screw is that it's removing material on the way in. In the case of wood, it would take less force, as it's not having to shove the fibers aside (added benefit of reduction in the chance of splitting). It's cutting wood fibers before the threads on the rest of the screw engage.

GaryB25 7 years ago

i tried it but i only have a 9" grinder so i lost a couple of fingers . but the screw works good.

shazni 7 years ago

This is great! I used to make the cut with an angle grinder...but obviously it wasn't easy without a jig. Thanks for the instructable. :-) It is very useful for me as I have to order self tapping nails from abroad and that is 3 times the price of a normal screw.!