What is a pilot drill bit? Is it different from an ordinary drill bit?

Question

Am I safe to use a 4mm normal masonary drill bit as a pilot, or do I need something different?

I've got some screws which can go straight in to masonary/brick walls - which suits me cause I usually have nig trouble trying to fit plugs in to walls.

quote: "No need for a plug or anchor sleeve! Just drill through the part being fixed to the masonry, then drive the screw in. Dual angle thread with hi-lo threadform. Extra hard steel with chromate finish."

but.....

quote: "Use 4mm pilot for 4.8mm screws and 5mm drill for 6.4mm screws."

***Am I safe to use a 4mm normal masonary drill bit as a pilot for my 4.8mm special masonary screws, or do I need something different ? I don't want to leave a big nasty hole in the wall from using the wrong sort of drill bit. Thanks.***

Answer 1

I have used these masonary screws, but in much larger sizes. From your quote, you MUST use a 4mm masonary drill, its not a pilot hole for a larger drill size, but a pilot hole to put the bolt into. The 0.8mm difference is for the hardened thread to cut into for a grip, i.e. 0.4mm all round. If you make the hole any bigger than 4.0mm the screw will just slide in!

Answer 2

Pilot Drill Bit

Answer 3

The term pilot hole is loosely used in this case. The finished hole size is 4mm for the 4.8mm screw.

Normally pilot holes are drilled when the finished hole size requires too much material e.g. steel, masonary or wood, to be removed in one go. It also helps in steadying the final size drill bit, but for this the pilot hole must not be close to the finish size as this would cause the final drill to wander.

As mentioned above the term pilot in your case is used to ensure a hole is drilled and that you don't attempt to screw in without a hole.

Answer 4

A pilot drill is just a term for a drill smaller than the actual hole you eventually need which is used to make a narrow hole to guide a larger drill or screw. The pilot drill should be appropriate to the medium you are drilling into, in your case a 4mm masonry drill is just what you want. Good luck with the project.

Answer 5

The word "pilot" is used to describe the hole that you are making, not the type of bit used.

The most important thing is that you are using the right bit (masonry) and the right size.

For ultimate clarity, the quote you provided above could have been written like this: "Use a 4mm masonry drill bit to create the pilot hole for 4.8mm screws and a 5mm drill bit to create the pilot hole for 6.4mm screws."

Answer 6

Some masonary screws have included with them a drill bit of the appropriate size. When that bit is not available they will instruct you to use a pilot bit(same as a drill bit) of a certain sixe so not to over size the hole.

Pilot hole or bit is just another word for guide or leader bit. nothing more. don't panic as long as oyu have correct size bit and you drill is correctly straight then you will be ok!

Answer 7

Yes a normal 4mm drill bit is fine. A pilot hole is simply a starter hole for accuracy with bigger drill bits.

Answer 8

A pilot drill bit is for making the initial pilot hole before drilling with the correct sized bit,It`s just so you get it right first time really.

Answer 9

yes durium tipped masonary drill as pilot hole is fine all pilot means is ,guide hole of a size smaller than your screws to allow them to be screwed in securely . there ok as long as wall is sound . although in all honesty proper size polythene rawlplugs & screws give a better job . screws your using are prone to snapping if overtightened or, if what your fixing gets a knock they have no give , brittle , same as many plasterboard fixings of same type self tapping screws

Answer 10

A pilot hole is one that that makes a path for a screw. Not a special drill bit. If you are making furniture or cabinets, special countersink/counterbore bits will drill a pilot hole, make a chamfer (countersink) and a larger hole at the top called a counterbore all in one operation.