A while back I saw someone on TV split a large piece of granite by drilling a series of holes and then inserting steel wedges and slowing pounding on them until it split in a nice line. I think the wedges may be called “plugs & feathers”. I’d like to try to do the same with a large boulder in my yard, but am wondering if anyone knows where I could get a set of these wedges?
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Replies
feathers & wedges..try looking for Barre Granite .. that's where i bought mine about 15 years ago....
or a good machinist can make you several sets from mild steel
Mike Smith Rhode Island : Design / Build / Repair / Restore
Lee Valley Tools sells them.
Try this link:
http://www.leevalley.com/garden/page.asp?SID=&ccurrency=1&page=10335&category=2,2180,41007
Barre Granite in Vermont is a good source, I usually go to Bicknell, in Rocland, Maine. You can reach them @ 1-207-594-8454. Or call O&G of Torrington CT. I last bought 1/2 feather & wedges from them @ $6.oo/set. A bit better than Lee Valley's price. Holy %$#@! Rod
Don't think you need to buy stuff to split one boulder. Some tapered punches ought to do the same thing.......
Sex is like pizza. When it's good, it's really good. When it's bad, it's still pretty good
I have only heard a little about this new technique:
You still drill the holes, but then fill them with a hydroscopic clay. And add water. The top part of the clay seal the hole but continues to wick water to the rest of the clay with creates high wnough pressures to split the rock. I'm not aure about hole sizes - larger diameter holes would be more effective with the clay technique.
But for one-time use, I'd agree with others: don't bother buying a set. Make a LOT of holes and use what steel stakes you can find/modify to a taper. (Concrete forming stakes and a grinder? Thinly tapered triangles of sheet metal and then the concrete stake? (So the cross section of all the metal increases with depth).
David Thomas Overlooking Cook Inlet in Kenai, Alaska
I'm having a hard time believing it takes less pressure to break the rock than to push the plug out of the hole. Where could I read more about this?
Forget making your own tools from tapered whatever! Unless you don't take into account what your time is worth. Chisels, screwdrivers, etc are too brittle (this is from experience), and to take the time to make your own is just plain ridiculous. They are available at a reasonable price. No fuss, no muss. For under $100.00 you can have a good set that will last you a lifetime (unless of course you decide to make your living from splitting stones).
Besides, you can then impress upon friends & family on the proper way to split a stone.
And look more professional while doing it.
Rod
As explained by the display at our local historical society:
Since water freezes from the surface down, the ice formed near the top of the hole bonds with the moisture in the pores of the sandstone, creating a tight lid, made tighter by the swelled oak plug residing above it.
Ever see an engine block crack and the freeze plugs stay put? Kind of the same theory I guess.
Ditch
I've never done it, but heard it from a reliable source some years ago. I'll try to contac him for info. I wondered about the plug getting forced out as well. But the ice serving as a plug for the water further in is an example of a similar scheme working.
David Thomas Overlooking Cook Inlet in Kenai, Alaska
I live in N.W. Pa. where we have a lot of old sandstone barn foundations. Some of the "blocks" are enormous: (5' long by 2' wide and 2' thick. Our local historical society has drawings of sandstone veins with holes drilled in them both vertically and horizontally (slight angle on the horizontal holes) in a straight line about 4" apart and 24" deep. The stone cutters filled the holes with water and plugged them with oak plugs. If they had a good, hard, cold winter the "line" would be split come spring. There is evidence locally that some of these "lines" were hundreds of feet long.
Ditch
I have heard that when water freezes it can create presures of around 3,000lbs/sqin.
When my dad and I were rebuilding a log cabin we had an old timer stone mason do the fireplace. Another method to spit according to him was to make a fire on top of the stones, get it nice and hot for several hours then pour water on it, the stones split. However, I never saw him do this, though most of the stones were smaller, between grapefruit and volleyball, he did most of the splitting using a 5lb hand sledge with the rocks resting on his leg. That was an old man the I had a lot of respect for. We put a brass plaque with his name on it nailed to a timber beam next to the fireplace.
The heat method is more likely to take flakes off the surface than to split it down centre. Using a torch and water spray is used to dress some stone
Excellence is its own reward!
edit- got to thinking that I should add that you should be sure to wear protective clothing and a face mask for when the schrapnel shards fly off.
Edited 9/1/2002 2:40:08 PM ET by piffin
The fire method was known in ancient times; one of the most famous accounts was Hannibal crossing the Alps and using fire/vinegar to fracture rocks.
http://web.bham.ac.uk/J.P.Pluck/.
Phill Giles
The Unionville Woodwright
Unionville, Ontario
Was also impressed by the water method used by the "old timers". On the Bald Face Mountains in New Hampshire can still see where it was used effectively with granite. Some pieces obviously broke and seems they never came back to collect the last batch the following Spring...My old barn foundation (circa 1860's) has granite steps. Still visible 3/4" by 4" holes spaced around 6" o.c. split the 12" depth (they placed the stones with the holes at the top--perhaps to remind others of the work involved?....)
Regards,
Rework
The hardest part is drilling the holes. Just any old drill won't hack it in granite. Even a carbide tipped drill will struggle. Quarries use diamond tipped equipment. The Feathers & wedges are also necessary if you don't want to get your wedge stuck on the sharp corners of the hole. That's why the feathers. Lets the wedge slip smooooothly and easily down the hole.
Another suggestion - get a dry diamond saw blade for a skill saw and cut a kerf on one side along the line of the desired break. Go as deeply as your saw will allow you, in roughly 1/4 inch steps. Then turn the stone over and take a good sized chisel and start working across the line of the kerf on the back side. Use about a 3 lb short handled sledge. Be patient, making many passes of moderate impact on the chisel. Stone will split beautifully straight along kerf.
Real stone masons doubleteam the rock, w/ an 8 lb long handled sledge and another sledge w/ a sharp edge on it held by a second man along the line of desired fracture. I've watched them cut blocks several feet in each dimension this way. They don't bother w/ the kerf, they just start whacking away, following the desired line all the way round the stone. Cuts straight as an arrow - if they judged the "Grain" of the stone correctly.
Wear gloves and face protection. It's dangerous from the flying chip standpoint.
Don The GlassMasterworks - If it scratches, I etch it!
If you're going to buy that diamond sawblade, and take the kerf route... Why not just kerf all the way around the rock. Then drive a chisel into the kerf just about anywhere, to finish splitting the rock.
Quittin' Time
Doing it his way, without the whole kerf will let the force from the chisle transmit straight DOWN ino the rock towards the opposite kerf. If you drive a chisle into a kerf cut, the pressure is to the side of the chisle where the shoulder wedges in before it comes into contact with the bottom of the kerf and the larger mass of the stone, Likely resulting in a small chunk splitting off to the side.
IMOExcellence is its own reward!
Thanks. That makes sense.
Quittin' Time
I've tried both methods. The stone does chip funny, as you said. The shock wave fromthe blow doesn't travel through the stone, and the kerf softens the blow. But... there's another reason - simplicity. Takes time & wear & tear on blade to cut kerf all way around. Takes very few passes w/ chisel to split stone w/ good kerf on top. And it does cut straight as an arrow if you get exactly opposite the kerf. I routinely do 3 inch stuff for corporate awards, etc. I did some 5 inch stuff for keystones over windows on new house. Worked just as well.
DonThe GlassMasterworks - If it scratches, I etch it!
If you live in the north where it freezes, just drill your holes and fill with water. let freeze over the winter and it will split the rock.
Trow and Holden in Vermont sells everything you could need. As others have suggested, it might be a bit pricy for one rock, but if you take a liking to stone work...
Pete
Meptmoore -
Sorry but NONE of the techniques listed above will work effectively except for traditional holes, wedges & feathers, which is a lot of work. However,
You need Bristar, otherwise known as chinese (actually Japanese) dynamite. IT goes into the rock drilled hole and splits the boulder. I've done at least 8 in my own yard including one diabase boulder over 10,000 lbs.
Here's the website: Bristar / Demolition Technologies
Happy splitting!
T. Jeffery Clarke
Edited 9/3/2002 11:31:25 PM ET by Jeff Clarke
Many thanks to all contributors of these great ideas and methods. I haven't figured out which I'll use yet, although the dynamite sounds interesting. Not sure my neighbors would agree though! Thanks again.
It's 'quiet' dynamite, more like the ice expanding trick except that it works, and works in a day or too. Drilling holes isn't much of a problem with a real rock drill, 100 HP compressor and 1 3/4" carbide bit, even in diabase (trap rock). Yes, the neighbors won't like the rock drill much :o/
T. Jeffery Clarke
Quidvis Recte Factum Quamvis Humile Praeclarum
(Whatever is built well, no matter how humble, is noble)
Edited 9/4/2002 9:39:22 PM ET by Jeff Clarke
I never had much problem. I just look at 'em crooked, and they breaks up themselves. If that don't work, I spits on 'em. Never fails.
I eats granite for breakfast. And sandstone for dessert at noon. When I walk by, them rocks just burrow theyselves further into the ground, out of fear.
I once went out to build a rock wall. The wall built itself before I could even get my gloves on. Just out of pure respect.
Quittin' Time
On Luka!
I heard he walked to school in the snow in bear feet, up hill, bothways. :) lol
You think I had it bad ?? You shooda seen the bear after I took his feets.
He couldn't go to school. He couldn't go to cub scouts. He never got his eagle badge. All the other scouts laughed at him. He lost his job and couldn't afford anymore tourist-kibble.
Now he lays stretched out, in front of fireplaces, in hopes of getting the leftover drunks after a party winds down.
He developed a really bad self-esteem problem. Sometimes I get really tired of him whining over a bottle of MD 20-20, until he passes out. One of these days, I am going to take his tongue too. I just haven't figured out what to use it for yet.
Quittin' Time
LOL, Gotta lern to uze dat spel chek huh!!!!!
Wow, I just figgered it out ! ! !
The clues were there all along . . . the North Woods, a dog named
Bear . . .
Luka is Paul Bunyan ! ! !
Greg.
The dog's name is Rufus. The bear's name is bear. Yeah, I know, but then bears aren't known for a heckuva lot of creativity when picking out a name for theyselves.
I try to keep that dog away from the road. He likes to chase cars. Which, I guess wouldn't be so bad if he didn't bury them every time he catches them. Besides, every time he steps on a truck, I end up with an insurance bill for the smashed truck.
It was a very funny scene the other day, when there were 4 or 5 large dump trucks running back and forth out front. Rusus got out there, and tied to stop two of them. They were going opposite directions. He ended up with one paw in the bed of each dump, and both dumps going breakneck speed down the hills, away from here. They made him do the splits, and he ended up knocking his chin on the roof of the neighbor's house.
When he got up, he looked at me like I was somehow responsible for his misfortune. Dumb dog. Just because I was rolling on the ground laughing...
Quittin' Time
one misspelled word and look what happens.............................oh well could be worse.................could be hi-jacked and end up on some subject like dogs and bears...............oops that is were we are now....................goodnight all.
Sounds like the meds are working too good. Send me some!
:)))Excellence is its own reward!
"I just look at 'em crooked, and they breaks up themselves. "
Thank you for not looking at'm straight. It would mean the end of the world.Excellence is its own reward!
Luka, you ain't had that tin foil hat on too tight, have ya ???
I'm really easy to get along with once you people learn to worship me.
Smiles all around!Excellence is its own reward!
Customer of mine had the same predicament. Large boulder just high enough to catch the mower blade. Tried the fire method, chisels, etc. Finally used drilled holes and high psi expanding grout, did the trick. Best of luck! Another thought, dig a hole and bury it:)
Brudoggie
Another device I've heard of consists of a continuous loop of steel cable, and a motor drive that makes it move sort of like a band saw blade, only with the stone in place of the idler of the band saw. This with an abrasive slurry is what does the cutting. IIRC, this setup was used on the move of the Cape Hatteras lighthouse.
-- J.S.