Will a carbide burr cut rock?

I've a hankering to date my work by carving "MMIV" in characters about

2-1/2" tall into a flat rock surface in a garden project I bust my hump completing over the last three weekends.

Can I do it "freehand" with a 1/4" or 5/16" carbide "ball" burr in a die grinder?

I don't own either now, but this might provide the excuse I need to aquire them. (I do have compressed air to run a die grinder with, but I don't think it's enough to try using abrasive blasting through a stencil.)

I don't know what kind of stone it is, I'm not a geologist, the rocks are just stuff which grows in the ground here.

I did something similar on a manageable size stone by using my drill press and pecking away with 5/16" masonry bit. It came out fine, but the stone I want to mark now is way too big to move into the shop and I wouldn't expect I'm deft enough to freehand it using a drill motor with a masonry bit in it.

Thanks guys,

Jeff

Reply to
Jeff Wisnia
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Granite or Talc?

Reply to
Ian Stirling

Hi Jeff,

If you have to buy the tools to do this job, you might consider checking with your local Harbor Freight for diamond coated tools. You may be able to buy one that fits the need, and they aren't expensive. They sell a variety of them, although they tend to be small sized. I used just such a tool, (diamond hole saw) to cut the openings in tile that went around the faucet set in our shower, allowing for full pieces to be installed instead of making various cuts to get the opening needed.

Unless you intend to cut relatively soft rock, the success you'll achieve with carbide will be somewhat disappointing due to very rapid edge wear. In essence, you're trying to shape a grinding wheel. Diamond will stand up to the hardest of rock with no trouble, where carbide would soon lose its ability to cut. If you find that there are no alternatives to your plan, I think you'd have some degree of success with carbide unless you're trying to carve the hardest of stone.

Harold

Reply to
Harold & Susan Vordos

I would use silicon carbide abrasive. You could hog out most of it with a 4.5 inch angle grinder and a silicon carbide disk. This give you a reason to buy both a die grinder and an angle grinder 8-).

I used a angle grinder to smooth out the top of a piece of granite for a seat in the yard. Fortunately it was close to smooth when I started.

Dan

Reply to
Dan Caster

Considered sandblast etching? Cut a rubber mask from 1/16" sheet (can trace from computer printout) and glue to surface. Sand eats stone, but bounces off rubber.

Reply to
Richard J Kinch

depends -a lot- on what kind of rock it is. fortunately, carbide burrs aren't all that expensive. get one and try it.

Reply to
bridger

Yes, No problem. You already know to wear eye protection and a filter mask so you don't breath the dust.

A desirable tool accquisition might be a 100K RPM small air diegrinder with 1/8" collet. Enco and Harbor Freight offer them for about $50. I like Kroil for lube in these tools. Squirt a shot of Kroil in the air line before each use. It works a treat.

Reply to
Don Foreman

Hey, good idea! I do have an angle grinder and a bunch of masonry cutting wheels sitting around waiting for their next job.

I'll give it a shot with the angle grinder. Fortunately, the letters I want to carve ("MMIV") reqire only straight lines, and I'm sure that if needed I can touch up the ends of those lines with a carbide masonry drill in a drill motor.

Thanks,

Jeff (Off to practice on a scrap stone...)

Reply to
Jeff Wisnia

Roman numbers do have a few advantages 8-).

Dan

Reply to
Dan Caster

Well, being a stone sculptor as well as working with metal (stainless and bronze), I could throw in my 2 cents worth here...

Harbor Freight and other bottom of the line stores, do sell diamond wheels (they look like regular 4.5" angle grinder wheels but are made of metal and have shiny, shiny diamonds on them. :-)

I would never use these things for what I do with stone, but for the 5-7 bucks they sell them for (verses $50 for good ones) I would suggest getting one of those. They can also handle the speed of the angle grinder and the IMPACT of working against stone (much more resistant to cutting than steel is)

On the roman numbers.... There's a REASON all of their numbers are straight lines.... Carving them was/is much easier!!! except for that damn "C" (50 I think) Maybe that was in tribute to Caesar?

James, Seattle

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Reply to
RainLover
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I believe that the 'C' is for "centum" (100), not Caesar. 50 is 'L'. The one for 500 'D' would also be a pain to carve. Everything else seems to be nice straight lines.

Enjoy, DoN.

Reply to
DoN. Nichols

Thanks for the Latin Lesson! :-) Lucky for me and my art, I'll never have to worry about carving 2100 or 2500 then! I'm all about the straight lines.

James, Seattle

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Reply to
RainLover

Very freehand, it is likely to skitter all over the rock. Why don't you do it the way the Romans did, with a hammer and rock chisel?

Gary

Reply to
Gary Coffman

Thanks to Dan Caster's suggestion, this afternoon I chalked "MMIV" on that protruding stone and used a 4-1/2" by 1/4" DeWalt masonry disk in my ten buck HF angle grinder to cut the lines and then deepened their ends with a 5/16" carbide tipped masonry drill in a 3/8 drill motor.

The letters are approximately 3-1/2" high with strokes about 3/8" wide by 1/4" deep.

I painted the letters black so I can admire them when I look out our bedroom window tomorrow morning.

Photos at:

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I was amazed to find when the job was done that the masonry disk had lost less than 1/16" of its diameter, 'cause that rock seemed pretty darn hard and took lots of passes to groove.

Jeff

Reply to
Jeff Wisnia

Reply to
Roy J

Funny you should mention that. We're in Red Sox country and my next door neighbor's new driveway *is* heated. It uses a gas fired hydronic heating furnace pushing antifreeze through buried plastic piping.

During the last year the neighbors added another story and a garage to their once modest little house. His contractors had to build a driveway ramp and landing pad in front of the garage which left us looking at a not very picturesque mess of stones, bricks, parts of concrete blocks, drooling concrete and Gawd knows what else they used as a facing to forstall erosion.

In self defense I hauled 15 five foot tall arborvitae shrubs back from the nearest Home Depot and planted them in a line where they do a pretty good job of breaking up the view. I also camouflaged some of the off colored parts of the rubble (with neighbor's blessings) with daubs of several different shades of earth colored paint.

That rock I "engraved" showed no signs of ending when I dug down about a foot alongside it, so I decided it was better to live with it than spend a fortune on a contractor to remove it, but it looked just too blank sitting there without something carved on it. (My first thoughts were to carve "J.H. 1913-1975", but SWMBO talked me out of that fast.

Our own driveway is pretty well sloped too, but not so bad that I can't keep it clear with my snowblower.

Jeff

Reply to
Jeff Wisnia

How deep did you cut with the grinder? I would be concerned with the masonry drill wanting to escape from the grooves. Did you use any special technique to prevent this?

Nicely done!

Ted

Reply to
Ted Edwards

I'd say I went about 3/16" to 1/4" deep with the 1/4" wide grinder wheel, then tilted it a bit to widen the top of the grooves to about 3/8".

I was sitting on a tarp on the ground and was able to rest my arms on my knees. I was suprised at how easily I could gently sweep the edge of the wheel along the chalk lines to get the cuts started. Once that was done, the wheel stayed in the grooves fine.

There waere no problems keeping the masonry drill where I wanted it once the grooves were there. Like the angle grinder, I hand held it with my arms resting on my knees. That masonry bit didn't seem to mind being abused as an ersatz router bit either.

I sure wouldn't want to do it that way for a living though. I'd say I spent about two hours on the project, but it was a coolish Sunday afternoon and SWMBO was off seeing Swan Lake at the Boston Ballet. I leave it to you to guess which I preferred to be doing.

And yes Don Foreman, I did wear an eye shield and a dust mask.

Reply to
Jeff Wisnia

I can't see how you did that without diamond. I would have cut it 3 times for each line with a 4" continuous diamond wheel and chiseled it.

Poor tree.

You said something about the neighbors' mess responding to another post, people here don't want you to park on their street to build the other neighbors' stuff. They have no clue to where we parked to do their stuff.

Mass. is weird , probably get in trouble cause it dates it. They don't even like new stone walls unless they look old. On one job they had to bring in a crew to cover the walls with cow manure and moss sprouts or take it down.

Oh , and I heard it as Gwad kinda like that thread that reminded me of R.I. How's it go ? Pwovidence Woe Iwand.

Reply to
Sunworshiper

From what I've seen tree roots do to sidewalks and stuff I believe that tree will likely take care of itself quite well.

Hey, I've gotten along with those neighbors for the dozen or so years since they moved in. I really can't blame them for not forking out another maybe $20K to have his contractor build a prettier wall that only we would see.

To my neighbor's credit though, after I was done planting those arborvitae he came over and offered to pay for the plants I'd just put in.

I've always felt that one's property rights extend to the edges of yone's property and as long as an abutter isn't doing something which smells foul or hurts your ears they should be free to do whatever's legal. And if you don't like what you see on the other side of your line, then screen it off, which is what I did with those arborvitae shrubs.

I refused his offer, but he insisted, so I asked him write a check to a local charity we support. That satisfied both of us.

That's probably true if the property has been declared an "Historic Site", but our neighborhood is only about 25 years old and folks here are building homes with new looking stone walls and even walls made from "regularly sized "artificial stones" every day.

Wuzzat Barbara Walters who posted that?

Jeff

Reply to
Jeff Wisnia

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