what drill bit to use

[tabita]

Hi all,
I think this is completely a novice question. I bought an IKEA bookshelf extension, and need to drill a hole into the top of my existing bookshelf.

bookshelf

• tabita
• 2 May 2015
• 1

If you refer to my image, I need to drill a hole that size, so I can fit that screw in. Does this require any special drill bits to allow the thread on the screw to hold?

Thanks!

 

[big-all]

suspect 5mm
whats at the other end off the thread is there a slot or flat edge to spanner off ??

 

[Burnerman]

A normal jobber twist drill will be fine, Tabita.....these are usually HSS (high speed steel) and can be used for drilling most materials, but not masonry.
You need to ascertain the size you need though, and the popular sizes come in half millimetre increments.
John

 

[JohnD]

an important question:

is this a hole that you want the screw to bite into, to fix something to it? What?

Or is it a hole that you want the screw to pass through in order to screw into something on the other side? What?

 

[tabita]

Untitled

• tabita
• 2 May 2015
• 1

The left image shows one of the screw has now been screwed onto the top of the bookshelf. The right image shows an extension bookshelf 'docking' onto the screw. The next step would be to tighten that plastic thing into that round recess. Am I making sense?

I have a 5mm drill bit that I have been using to drill into drywall. I think I also have drill bits for wood(?) lying around.[/img]

 

[big-all]

ahh camb dowels
what you are after is the hole to be less than the threaded part but bigger than the shaft on the threaded part
you could try it on a scrap off wood or board or on a hidden area
but do not use a power tool when screwing home

 

[tabita]

Hi all,
Thanks for all the input. I used a 4.8mm drill bit I have lying around. I measured the dowel shaft to be 4mm, and the threaded portion to be 5mm. I note however that the existing hole was 5mm. Anyway, I made a 4mm hole, and it was too tight. 4.8mm felt minimally tight, so I went with it.

The extension shelves are sitting quite nicely and feels secure.

 

[big-all]

thanks for the feedback
if it does work loose then wood glue / no nails in the hole before screwing in will help