Wood vs. Masonry Bits

[Beerman]

Dumb question.

I have a work truck with a BUNCH of misc. drill bits that were on the truck when it came my way.

For the longer ones we use at work, the spiraling goes most of the way up the length of the bit on the masonry ones. The ones designed for wood, the spiraling only goes up part of the way.

How do I tell on shorter bits(4-6 in length) weather it's a masonry bit or wood bit?

TIA.


Beerman

 

[Fretters]

The tips are completely different between wood and masonry bits.

 

[Dustball]

Google masonry drill tip and you'll see many pictures showing what it looks like.

 

[cheechi]

are any of those SDS bits?

IF they're just regular shank bits for smaller diameters, 1/2" and under, you will see masonry bits look like they have an arrowhead at the tip.

There is probably a better way to describe it. I think from your description, most of what you have are augur bits that are mostly for wood. how much of the overall bit is fluted is more dependent on the depth of the hole you need and in some cases also the material, as well as depending on the manufacturer for the inexpensive, construction type you will get at the big box store.

 

[uart]

Dumb question.

I have a work truck with a BUNCH of misc. drill bits that were on the truck when it came my way.

For the longer ones we use at work, the spiraling goes most of the way up the length of the bit on the masonry ones. The ones designed for wood, the spiraling only goes up part of the way.

How do I tell on shorter bits(4-6 in length) weather it's a masonry bit or wood bit?

TIA.


Beerman

Like other have said, the tips should look completely different.

The most common type of masonry drill will look like a little carbide arrow point brazed onto the steel shaft.

There are various different types of wood bits, but the long ones you describe sound like auger bits. These typically have a little screw type point on the end, with a relatively flat (180 degree) cutting edge following that up.

The short 4" to 6" ones may have tips that are different to both of the above, is that correct? They may just be standard 118 degree HSS, in which case you can use them in metal or wood, but not masonry. Or they may be brad-points, in which case they'd have a sharp little (non screw) point on the end and be only for wood.

Describe what tips look like on the little ones, or post a picture.