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I need to drill a 16mm (5/8") hole in a concrete wall. All I have is a 20V DeWALT DCD795 drill (which has a drill driver and hammer feature) and the appropriate drill bit.

Someone suggested to me this won't be sufficient and I risk breaking my drill if I try. Renting gear isn't an option where I am (Thailand), and I'd rather not buy more gear.

Any comments, thoughts or suggestions are welcome!

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    What is "a concrete wall"? Block? Poured? 6"? 12"? That's a very large hole for most cordless drills, and you'll be putting a fair bit of wear on it if we're talking solid concrete. You'll be running it for 10-30 minutes or more to do this job. – isherwood Feb 25 at 14:15
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    I think this is one of those situations where you'll be fine doing a few holes, but if this is a regular task, you will want a bigger drill. I agree with the posted answer by Alaska, but I wouldn't expect the drill to do it often. – JPhi1618 Feb 25 at 15:12
  • How deep is the hole and how many holes? – Freiheit Feb 25 at 17:18
  • How deep do you need to go? I have drilled about 2 inches (5 cm) in solid concrete with some effort and such a drill. A proper rotary hammer makes the task easy. – Ross Millikan Feb 25 at 17:18
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    Even if you can't find a bona fide Tool Rental Shop, you might be able to find and rent from a private individual or hire a contractor/handyman to do the job for an equivalent or cheaper cost. You may also be able to 'rent' by buying a used tool, then selling it forward. – Timbo Feb 25 at 23:51
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I am not sure why they would tell you that it may ruin your drill. It might not be the most powerful hammer drill but it should be up for the job if you take the time to do it in stages.

If you cannot rent and you do not want to buy a more robust hammer drill you’re only left with one option.

I would start with a 3/16 inch masonry bit and see how that goes. Then move up to 1/4 inch or 3/8 then to 1/2 inch and finally 5/8.

It will be easier for the drill to start with a small drill bit, once you have that hole cleared then successfully moving up in size will be less stress on the drill. If it struggles with any of those stages then you may have to do smaller incremental stages.

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    I agree.... start with smaller drill bits and work up... Use moderate pressure on the drill, Let the drill do the work.+ – JACK Feb 25 at 13:02
  • Good answer cheers. +1. – Solar Mike Feb 25 at 17:52
  • It's somewhat likely to wear out the drill bit, but not very likely to damage the drill itself. – jpa Feb 26 at 15:40
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It depends on the concrete. I have flown through some concrete with the dullest of bits and a cheap hammer drill and have had major issues other times when I did not have a good hammer drill.

I am on the fence with starting with a smaller bit. I do go to that if I see it is going slow and sometimes it helps and sometimes it doesn't.

I will say this. I have bought many a cheap hammer drill, used the hell out of them the day I bought them, and returned them the same day - usually hammering motor malfunction or electrical issue. I would not use something I want to keep unless I knew it could do the job.

So two options:

  1. Use it in 10-15 second increments, clean hole and make sure you are making progress. If you aren't stop using it.
  2. If your drill isn't working use a hammer and a pick. You can actually use this method in conjunction with your drill.
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    Seconded. I've used plenty of cordless drills with a hammer feature, and they're fine for a couple holes. And the material makes a big difference. But if you're doing a lot of drilling, you need a dedicated hammerdrill to avoid burnout and to make good time. And with either, you need to make sure to keep the hole clean to reduce friction and risk of breaking the bit. – brichins Feb 26 at 0:48
  • Find out, and then take it back to the store, +1. I've been using the same one for over 10y. I'd seriously consider not because of its age, but a new one I want to know if it's worth replacing the trigger in 5y. It's a Dewalt so I'd expect yes. – Mazura Feb 26 at 3:11
  • @Mazura - A good hammer drill is a must if you are doing a lot of concrete work. If you just have a small job it and may never do it again... hard to justify buying one for $150-200... I have a good one and if I don't have it on my I wouldn't think about burning out a good drill. I have gone to HF and burned through their $30 variety after 3 holes. – DMoore Feb 26 at 23:29
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Nearly burnt up an inexpensive corded hammer drill on just one (of 8 needed) 3/8" holes in 30 year cured front walkway.

Went and rented a HILTI and holy smokes. Not much bigger but it just walked through the concrete making holes.

If yours is a cordless it'll be lots of re-charges. If a 1" cordless Makita you've got a chance.

The main thing to watch is heat. If the drill is getting HOT then let it cool down.

Which leads to the next thing - your time and frustration. If only one hole and a powerful drill it may be doable but tiring. Any more. Just rent the HILTI.

Concrete block also - is hollow - so not so much an issue as hardened concrete or brick or such.

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    Holy smokes, indeed. You'll ask yourself WTF was I doing.... – Mazura Feb 26 at 3:04
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    true, but they are called HILTI... – clambake Feb 26 at 6:35
  • HILTI is not the only brand of rotary hammer drill (anymore): most look-likes are adequate substitutes. – Jasen Feb 29 at 23:12

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