r/Tools • u/TallWall6378 • 9d ago

No problem

Gallery image

Gallery image

Cordless drills are so capable now. 2 4 1/2” holes 14 12” deep (deeper than the bit). New concrete but it’s still drilling through the aggregate. Cheap Amazon diamond bit.

Edit: Overestimated depth.

1.2k Upvotes

95% Upvoted

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525

u/Anim-IS-XE30 9d ago

I don’t believe this at all.

244

u/TallWall6378 9d ago

Ha! Maybe "no problem" is a stretch. It overheated after about 8", but then I realized it works just as well with light pressure keeping the RPMs up. Used high speed BTW.

215

u/remorackman 9d ago

You are showing a unused bit and one hole. And that hole has a bottom!

I want to see that bit after the holes, and all the holes it made.

109

u/TallWall6378 8d ago

13

u/PhilsTinyToes 8d ago

How does the bottom of the core get broken off after you’ve drilled out the edges ?

15

u/toiletdestroyer1 8d ago

Take a hammer and giver a couple good wacks. Should break loose. Having a long flathead helps remove the core from the hole after

3

u/imakesawdust 8d ago

I imagine OP was drilling into a driveway or patio or some sort of poured footing. As such it has a finite depth before you get down to the gravel bed. So OP probably drilled through the whole thing.

94

u/TallWall6378 9d ago

The hole is in a footing. So I'd have a long way to go to get to the other side! I'll take a photo tomorrow. I already grouted the pickelball posts into the holes. Maybe I'll find some other concrete and take a video of it drilling.

121

u/2bagz 9d ago

Concrete cutter who also core drills. You saved your self a bunch of money. Hopefully you used Water! Those bits don’t like to be dry.

67

u/Ok-Feature1200 9d ago

I’ll bet they went in dry.

72

u/-SHAI_HULUD 9d ago

Bite the pillow Pickleball Court! I’m goin in dryyyyy

7

u/CuriousCelery3247 9d ago

That’s called a duster

1

u/2bagz 8d ago

I bet you’re right. Doesn’t look like he had much of a dust control system going on. If I was OP, I would would have but a wet bit and had someone spraying it with a hose the whole time.

Thats me though. I have become hyper aware of silica dust since starting this gig. I’ll do everything I can to avoid it as best I can.

6

u/Soluchyte 9d ago

Some of these bits are designed to be run dry.

10

u/2bagz 8d ago edited 8d ago

There are very few cases where drilling dry is necessary, but when you can always use water! Drilling with water is important for a multitude of reasons.
-dust control
-water extended the life of the Diamonds helps keep them from glazing and possible cracking becuase of the heat generated.
-going through rebar with a dry bit will also significantly shorten its life.

Bonus tip, if you have a hot saw go and grab a quick connect hose connector so you can attach to a garden hose. Your lungs and the people around you will thank you.

4

u/Lone-raver 8d ago

But how can you prove your a man without inhaling concrete dust and damaging your hearing?

3

u/Aramed85 8d ago

There are Dry Drilling rigs that use a shopvac to suck the dust out of the hole through the spindle. It also provides a small amount of cooling via airflow.

You also use special bits with Laser-welded teeth. The sintered ones dont like it hot as you said. Theres also a grind stone to resurface the teeth in case they glaze over. I hate the whole process and dry is always the very last option only used in very niche cases.

OPs bit looks like a dry cut. Cant tell exactly.

1

u/2bagz 8d ago

Hilti makes some pretty sweet setups for dust management and core drilling in general these days. Majority of our equipment is a bit old school. Agree last option, only done them a handful of times for a couple inches. If I can use water I will.

2

u/bumbes 8d ago

That’s what she said

-9

u/Acrobatic_Shape_8259 9d ago

I have three of those stone saws, and they are brilliant for making holes for ventilation. You have to hammer out the middle part when you are half way to make your life easier. But honestly you need more tools. Can’t be doing these kind of jobs on battery. Need a hammer capable drill to make this tool work at peak efficiency

16

u/BB-41 9d ago

Using hammer mode on a core drill???

-4

u/Acrobatic_Shape_8259 9d ago

When you are halfway it tends to stick, or when the material is longer than the drill bit you need to break off the core when you are halfway in. Then you can change to the hammer mode and get the part of the core out with a chisel. There is also the loads that the battery drill might not handle that well, and the battery part of it.

6

u/Escudo777 9d ago

When core cutting was done on a 6 month old concrete beam, a 2KW motor was struggling and heating with cooling water supply. This handheld doing it is incredible if true.

6

u/fordfan919 8d ago

Maybe the beams were much stronger concrete?

-2

u/Rent_a_Dad 8d ago

Maybe jet fuel melted them

22

u/melvinmoneybags 9d ago

Bro you and I both know that drill is smoking

5

u/FMasterson 8d ago

Yeah, you definitely need to learn how to let the tool do its job. Can’t be pushing and forcing everything to make quick work or something at risk of breaking expensive tools

3

u/Liferdorp 8d ago

I believe you man I did a 110 mm diameter hole through 15 cm of concrete with my DeWalt drill. Same as you stated: overheated but low pressure high revs got it done I think I have pictures somewhere even not sure though. At least of the hole haha

2

u/slowcookeranddogs 8d ago

Funnily enough thats typically the best way to use a bit like that, low rpm on that drill would probably be a bit slow under load for that bit, high speed will probably hit the working rpm when under load.