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How to use drill gauge to measure drill bit diameter?

Dear folk

I have got 3 Drill gauge with corresponding holes trying to use them to recognize a drill bit diameter size specially when I don't have a tag for the drill to reveal its size

I did a test for two drill bits that have their tags attached which are 6mm and 16mm but when I tried to push them the gauge holes they don't go through ,,,,,,what Am I doing wrong

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And video link below :

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Noyade

Hi @zillah

My thinking is the templates are designed for wood/steel drilling bits - not SDS masonry drills with tungsten 'wings' attached.

Cheers.

JacobZ

Hi @zillah,

I'm thinking much the same thing as @Noyade in that your drill gauges are designed for wood/steel drill bits, which don't have the wings at the tip. You are not doing anything wrong; masonry bits are just designed differently.

Masonry bits are very slightly oversized to ensure that masonry anchors, which work via expansion, are able to comfortably fit into the hole. As masonry anchors work via expansion, being 0.1 or 0.2mm larger than stated is not really an issue, as the expansion will take up this space. Being slightly oversized is also beneficial as masonry bits are extremely prone to wear, and being ever so slightly oversized means they can wear for longer before they are unusable.

If you can push it through lets say the 9mm hole, comfortably, and it looks like it should fit through the 8mm hole, but it just catches, I'd say it is designed to work with 8mm masonry anchors.

Let me know if you have any further questions.

Jacob

Noyade

I'm doubting my sanity and logic now @JacobZ and @zillah

Playing with templates and various style drills outside - I'm getting mixed results.

Sutton people would know?

But it's too hot - predicting 39 deg.C today.

zillah

Thx Noyade

What size of bit are you trying into the hole ? I guess it is metal bit not masonry

zillah

Thx Jacob

>>'m thinking much the same thing as @Noyade in that your drill gauges are designed for wood/steel drill bits, which don't have the wings at the tip. You are not doing anything wrong; masonry bits are just designed differently.<<

It makes sense wing at the tip of a masonry bit is the culprit

I have few masonry bits don't have their tags are there a drill gauge with corresponding holes designated to them ?

JacobZ

Hi @zillah,

Unfortunately, no, not that I am aware of.

If you couldn't work out the size of the drill bit using something like a ruler or tape measure, then maybe a pair of Calipers would be handy.

Let me know what you think.

Jacob

zillah

Thanks Jacob for your help

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