Drilling Pilot Hole

[No Blue Collar Skills]

Isn't it true that if the screw's diameter is, e.g., 3/16", the drill bit should be smaller, e.g., 1/8"; otherwise the screw threads will not have anything to "bite" into?

[John Grabowski]

• Yes. Here is a chart that will help you determine the proper hole size:

[pheeh.zero]

Absolutely, rule-of-thumb is the diameter of the screws body (not counting the thread) Also varies with the material you are fastening to.

[Jeff Wisnia]

Of course....

Regarding the appropriate size drills, you'd get more appropriate answers if you told us what kind of screws you're asking about.

Wood screws?

Self threading screws with fine threads?

"Sheet metal" screws ?

Lag bolts?

Etc, etc, and so on....

Re "No Blue Collar Skills", orthopedic surgeons have to be concerned about the same issues when they are driving screws into peoples bones, and I hardly think of them as "Blue Collar" types.

Jeff

[Phisherman]

Metal, soft wood, or hard wood? There are charts for finding the recommended pilot hole (and possibly shank hole) for various materials. Pine requires a smaller hole than hickory. Some hardwoods will split or possibly break a screw if the pilot hole is too small.

[Ed Pawlowski]

Are you talking wood screws? Yes, the pilot hole is usually the size of the shank. There are tapered bit that work even better with the matching screw size.

Depending on how sophisticated you want to get and how many screws you will be using, check this stuff out. The first one will give you the sizes you need for each screw size too.

?c=2&p=48336&cat=1,180,42240

[mm]

So you're saying he has no orthopedic surgical skills either!

I'll bet he doesn't know how to toboggin, either.