Drilling holes in rocks - Help

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Harold_V
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Re: Drilling holes in rocks - Help

Post by Harold_V » Wed Jan 22, 2020 1:31 am

carlquib wrote:
Tue Jan 21, 2020 6:42 pm
I'm a Hilti fan.<snip>
Been using them since I was a kid in the fab shop. I would stay away from anything that uses the opposing steps to generate the percussive force. I went down that route and they don't work to drill anything very hard. I generally look for something that you can select drill, hammer/drill or just hammer. The hammer only setting will give you a clue to how the percusive force is generated. There are also cheaper versions out there or you can just rent if it is going to be a one time need. Once you have experienced a real hammer drill you won't want to go back to anything else.
I've had only one experience with a Hilti, but I recommend them highly after wearing out one of those less than useful hammer drills, the type with the opposing steps. My experiences parallel those above---the opposing steps beat you to death and do precious little to the concrete (or rock) being drilled.

When I built the castle, I had a buddy from my youth do the plumbing, although I worked along with him, helping where I could. One of the things he asked me to do was drill the hole through the 10" thick foundation for the water main (which was 1" copper pipe). Having used hammer drills, I dreaded the thoughts, but he handed me his Hilti and I started drilling. I had a hole in almost no time, in sharp contrast to much shallower holes of a smaller size I had drilled on numerous occasions. How I wish I had purchased a Hilti at the outset, instead of wasting money on those hammer drills.

H
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liveaboard
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Re: Drilling holes in rocks - Help

Post by liveaboard » Wed Jan 22, 2020 5:01 am

Hilti is the Rolls Royce of handheld power tools; top quality and topper price.
Some years ago I had a lump of concrete I needed to drill, and since I never worked with masonry at that time I borrowed a Hilti hammer drill from my neighbor. who did that sort of thing for a living
It broke.
Etiquette being what it is, I took it to Hilti for repair, which cost more than a cheaper hammer drill.
Some years later, I needed another hole in concrete; since I'd paid a fortune for it anyway, I asked my neighbor if I could borrow the Hilti again.
He said it broke again, he does a lot of drilling.
He'd switched to no-name Chinese box store hammer drills; 100-150 bucks. Just throw it away when it breaks.

Heresy!

Yet he claimed that they work just fine, for 1/2 as long as a Hilti at 1/4 the cost of a Hilti.
The Hilti is like gold, you have to worry about theft too [in a city setting where we were].

I used a big cheapo to drill a 3" hole through 18" of concrete and some rock, as well as a lot of other work on my house in Portugal.
The head bearings are shot and there seems to be no way the remove them, and I really should just buy a new drill.
It will only cost a bit more than new bearings.
The cheap drill has a safety clutch, switches 3 ways [drill, hammer, hammer drill].
In this picture I'm using it in drill mode to drive a boring tool I made,
bore cutter guide assembly.jpg

Chris Smith
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Re: Drilling holes in rocks - Help

Post by Chris Smith » Wed Jan 22, 2020 12:01 pm

I have had a Hilti for about 12 years. Cost a fortune but it is as good as when I bought it. If you can justify the cost then get one.

Chris Smith

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warmstrong1955
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Re: Drilling holes in rocks - Help

Post by warmstrong1955 » Wed Jan 22, 2020 12:24 pm

It used to be, that you bought a Hilti, or some other sorry substitute. That was all we used to buy in the mines for many years. Other brands just didn't hold up.
Not the case anymore. Nothing wrong with Hilti, they are good tools, but there are many other brands that are good tools, and they don't come with the Hilti price tag.
They also make a lot of other neat stuff, like laser distance meters. :)

Bill
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liveaboard
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Re: Drilling holes in rocks - Help

Post by liveaboard » Wed Jan 22, 2020 2:15 pm

I have an old Hilt cartridge hammer; put hundreds of nails through 2" of wood and 1/4" of steel.
works fast, holds fast.

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warmstrong1955
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Re: Drilling holes in rocks - Help

Post by warmstrong1955 » Wed Jan 22, 2020 3:09 pm

liveaboard wrote:
Wed Jan 22, 2020 2:15 pm
I have an old Hilt cartridge hammer; put hundreds of nails through 2" of wood and 1/4" of steel.
works fast, holds fast.

Those things are great, essential where you don't have air or power, and before the advent of the modern battery. They still have blazing speed in comparison too.
Used them a lot, in concrete, and setting up forms, and some timber work.
Talk about spendy beasts, but, all said, a money saver.

Bill
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liveaboard
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Re: Drilling holes in rocks - Help

Post by liveaboard » Wed Jan 22, 2020 4:53 pm

Cartridges were expensive; the nails too. I used to look out for used ones and got a stack of someone's old leftover cartridges but had to but the nails new.
80 cents to a dollar a shot as I recall; not so cheap.
But the alternatives for attaching the interior wood to the steel beams of my boats were less fun
Self drilling self tapping screws; overhead, hundreds of them? No thanks.
I'm the only person I know who did it that way though. Everyone else used screws or wedges.

Interesting how the nails would penetrate the steel; the metal would flower outward at the exit point. If the head was a little too high, it could be pounded deeper with a big hammer.
But they will not come out. Errors have to be ground off.
P0000598.JPG

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seal killer
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Re: Drilling holes in rocks - Help

Post by seal killer » Wed Jan 22, 2020 6:17 pm

pete--

Re: Retaining wall drainage

This wall is built from those 2400lb 2'x2'x4' concrete blocks you mentioned, plus a few 3500lb 2'x2'x6' blocks I had to use after my little block supplier went out of business. (BTW, I gave $30/ea for the 2400lb blocks, delivered [40+ miles]. With my new supplier of the 3500lb blocks, I pay $45/ea and I have to pick them up.)

The wall is finished except I am going to extend it westward (out further in the yard) another 12 or 18 feet. Plus, I may put some kind of finish on it. Stucco, maybe. Maybe something else to pretty it up a bit.

As you can see, it is 10' high and I stepped it back half a block after the second block. But, the important thing is the drainage. The hole that was there was the slope created by the excavator removing the material excavated for the house. It was a little less than 45*. Not big until you decide it needs to be level with the grade line of the house!

The lower four feet was filled with boulders from 150lbs to ~500lbs. There is NO fill other than rocks in the entire thing. I'm very careful about drainage in every project I build. If it doesn't drain well, it will be a temporary structure.

After the boulders, I used 6" - 1' river rock. What you see on top is a couple of feet of smaller river rock. After I figure out how to keep soil from filtering down into the rock, I will bring it up to grade (level with the top of the blocks) with topsoil. (Suggestions on how to keep the top soil on top?)

I built this using the Komatsu skid steer. Before I got the smaller, gravel size rock in place, I had to build "roads" out of white gravel to place some of the blocks. This spared my tires. Two years ago, they were brand new, stickers still in place. They are due to be replaced.

--Bill
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seal killer
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Re: Drilling holes in rocks - Help

Post by seal killer » Wed Jan 22, 2020 6:32 pm

All--

Here is the drill I bought . . . it is an SDS Plus machine: Makita HR2641X1.

I KNEW from the get go that I wanted an SDS Plus rotary hammer drill. Not because I have ANY experience with them, but I asked a contractor that is doing some work for me what to get for my rock project. He said to definitely get the SDS Plus or SDS Max. (At the time, they were just "words" to me. Still are, but I have one now.)

I THOUGHT I had. I was shopping at Home Depot, found one in the display and then had to find it in the storage area down below. I picked up the wrong box. Home Depot made it easy for me to fix that mistake.

Thank you for the help!

--Bill
ps I got a "free" angle grinder with it.
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pete
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Re: Drilling holes in rocks - Help

Post by pete » Wed Jan 22, 2020 7:08 pm

Proper terminology between locations and country's can vary a lot Bill. When I was up in Ft. St John almost all of the native sub soils was scraped in or ground up by ice age glaciers. All of it has a high clay content so it's a massive problem any time it rains for more than 10 minutes. Get off a black top or graveled road and tire chains are mandatory to be carried in case it rains. All weather non paved roads (compacted and crowned gravel) needed to be kept separated from that clay material or it starts to move into the roads gravel surface. I only know the materials name as Filter Cloth. It doesn't allow the gravel or native sub soil to move between the two materials yet it still allows any water to pass through the filter. It passes water in only one direction, down, and it doesn't allow water to move upwards. I'm sure there's something like it available around your area you could use between the gravel or top soil surface and the rock back fill to keep from losing that covering material. Plastic sheeting can some what work, but it's weak, easy to tear on any sharp rock and isn't all that good for it's permanent life span. It also collects instead of draining the water so imo it's an all round poor choice. I covered miles of that filter cloth grading out crushed gravel hauled in and rough spread with bottom dump trailers.

After a thought though, with top soil and anything planted in it that fast water drainage might cause plant issues if the water isn't retained at least partially. For graveled areas that filter cloth would work fine. With top soil maybe ask a gardening business what might work. None of my jobs were ever about plants and there preservation. At most I knocked em over and built a burn pile with them. Or loaded it out.
Last edited by pete on Wed Jan 22, 2020 8:45 pm, edited 1 time in total.

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warmstrong1955
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Re: Drilling holes in rocks - Help

Post by warmstrong1955 » Wed Jan 22, 2020 7:17 pm

I have done very well with Makita tools. I suspect you will be quite happy. (And nothing like a free grinder!)
Good choice on going 120VAC! More power!

For holding topsoil, up or down, look up and research Typar, or similar filter fabrics. It was used extensively in Alaska, but for the opposite reason, to hold the aggregate up top, and keep it from disappearing into the soil, which in most cases in Southeast, was muskeg. Crushed rock roads, just go away without using the stuff up there.
Tough stuff, and is very good at stabilizing soil....which ever way you need to stabilize it, and It allows water to drain through it. It comes in different sizes of mesh, and different thickness's.

Other Bill
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warmstrong1955
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Re: Drilling holes in rocks - Help

Post by warmstrong1955 » Wed Jan 22, 2020 7:18 pm

Pete knows what I'm talking about!

:)
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