What Size Masonry Bit For 8.8 Screw

Screw Gauge, Metric, Size, Clearance Holes, Pilot Holes & Wall Plugs

which wall plug to choose

Which one to choose?

I've explained this screw information in an easy to understand tabular array considering I find manufacturers recommendations are oftentimes vague and full general, I mean; why not exist specific? I understand in that location's a 'range' only why non give us the 'platonic' measurement, considering generally we have a choice?

The table beneath shows you:

Metric equivalents to imperial gauge.
What size pilot hole to drill in timber substrates for the all-time screw grip.
What size clearance hole to drill through the timber beingness fixed.
Which size plastic wall plug to use with each spiral size or gauge.

Righty-ho, lets jump right in…. (you can download a gratis PDF of this table at the lesser)

Gauge	Metric equiv.	Pilot hole	Clearance hole	Masonry plug size
3	2.5mm	ane.0mm	three.0mm	Xanthous (5mm pigsty)
4	3.0mm	ane.5mm	iii.5mm	Yellow (5mm hole)
6	3.5mm	2.0mm	4.0mm	Ruby-red (6mm pigsty)
viii	4.0mm	2.5mm	4.5mm	Reddish (6mm hole) or Brown (7mm pigsty)
ten	5.0mm	3.0mm	5.5mm	Brown (7mm hole)
12	v.5mm	three.5mm	6.0mm	Brown (7mm hole)
14	half-dozen.5mm	4.0mm	vii.0mm	Blue (10mm hole)

(click to download and print the screws explained table as a PDF to keep for reference)

Pilot holes and clearance holes in more than detail…

(I got a few emails well-nigh this….. :-))

screw holes explained in detail pilot hole and clearance holes

If y'all're not sure what all these holes exercise; hither'southward a brief explanation….

How tight is tight?

The airplane pilot hole recommendations in the chart are typical for softwoods. Hardwoods may well need a slightly larger pilot hole. If the spiral starts to become too tight, then it's advisable to back out and re-drill a larger pilot pigsty rather than gamble breaking a screw (you'll exist having a very bad mean solar day if you snap a screw…..).

In fact, if any screw starts to get very tight, it'south all-time to terminate and take a rethink before yous pause the screw or burst the textile. Screws should be tight, only not crazy, "sweating to get them in" tight! Simply hit reverse and take information technology out.

And so you'll need to consider whether to use a smaller estimate screw or drill a larger pilot hole if it's in wood. In masonry you ever have the option to re-drill the hole 1 size bigger (drilling through the existing wall plug) and utilise a bigger plug, cerise up to brown for case.

Full general Tips

Incidentally, guess relates to the thickness of a spiral's shank or body and only relates to imperial sized screws. Metric screws are simply measured and the thickness is given in millimeters. The metric screw equivalent size is approximate, but since we're heading that way, we need to learn and become used to them!

Past coincidence, the size of an imperial screw head also roughly equates to the gauge. For example an 8-gauge screw has an 8mm broad head…..handy huh?

How deep does a wall plug demand to exist? I talked about this a lot on another mail, hither's the link: How to Properly Employ Wall Plugs

Parting note about wall plugs: Exist enlightened that not everyone follows the color 'rules', one leading brands plugs are all greyness for case, and others are, well; they can exist any colour under the sun (every bit the above photo of my box shows). Blue wall plugs are another example, they can exist either 8mm or 10mm, go figure! If in doubt always measure the plug at the thicker terminate to make sure it's right for the size hole you have drilled.

Hope that helps you sort out your spiral dilemmas. Feel free to send this to anyone yous know who needs their 'screws explained' lol! And don't forget to allow me know how you go on. Incidentally if yous desire to assist support this site, catch your… screws etc. from ebay… Ta muchly!

Stay well

Ian