I am in Indonesia. I previously rented a jack hammer, which ended up costing around $175 for a week. The jack hammer appeared to be an old Hitachi H65.

We wanted the jack hammer to break limestone rock, and for concrete.

The jack hammer completely failed to do anything with the rock. I suspect this was because in Indonesia there is a great tendency to cut corners with poor quality tools; in this case the bit (not an original part I guess) seemed to be of very soft metal, so it was useless.

Now we are in the position where we need a tool to break relatively substantial quantities of rock, say a cubic metre or more off of a much larger (say 200 cubic metres) rock. And we also want to drill a rock to insert 16mm steel rods.

So I am looking at buying a larger rotary hammer, which is likely to be a Makita or Bosch, as that's what's generally available here. Labour is cheap here (less than $10/day), so there's not a great payoff in spending more money to save time - the machine just needs to stand up to the job.

Is there a strength the machine needs to have to destroy my rock? And what kind of technique and bits should be used to break the rock?

closed as off-topic by isherwood, mmathis, Daniel Griscom, ThreePhaseEel, Tyson Apr 18 '18 at 0:37

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  • Is this really home improvement? – keshlam Jun 11 '16 at 7:46
  • "Home Improvement is a question and answer site for contractors and serious DIYers. The core of this site is around parts of your home that are typically included when you buy or sell it, the structure, utilities, and major appliances." – thelawnet Jun 11 '16 at 14:32

This is an old question but I will answer it for any who land here. This job is probably too large for chipping with a rotary hammer, but that depends on the toughness of the rock.

Renting a diesel compressor, 2" rock drill and rock splitter would solve this problem quickly. Another solution if a rock splitter is unavailable or too expensive is to use an expanding rock splitting grout such as Apex Nexpro, Ecobust or Dexpan. The grout is pored as a liquid into a pattern of drilled holes, and expands with massive force as it cures, destroying rock or concrete non-explosively.

  • Are those products that are readily available in hardware stores? Can you post links to the products? Can you post links to more detail on how to use them? – fixer1234 Apr 17 '18 at 0:37
  • @fixer1234 Search demolition grout at Home Depot, Amazon.com, etc. – steve_tf Apr 18 '18 at 15:31
  • dexpan.com/… – steve_tf Apr 18 '18 at 15:34

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