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How to carve stone

Stoneshaper's "How to" page

How do you get started?


How do I start out?

That's the million dollar question. There are a number of ways. I took an art class in college and there was an art student that had finished a piece in stone. It was so beautiful that I had to try it. I brought a stone from the instructor and with tools that he lent me, I headed home. Two months later (I had to work in private as it was a mother's day gift for my wife) Mother and Child Reunion was born and I became a stone addict.

So you have a number of choices to make. You can,

  • 1) Take an art class in college.
  • 2) Ask the local colleges if they are going to have a stone-carving workshop.
  • 3) Go to the library and take out a book on stone carving and use the resources at the end of this page to get your supplies.

What you're going to spend your money on

Stone

Availability of carving stone

Depending on where you live, you can probably find SOME kind of stone to carve within driving distance. This is what I do to get my limestone. Other stones are available but shipping can hurt the old pocketbook so I would recommend that you try the local schools for stone supplies or information (excellent idea). They often keep a supply on hand for the students and are usually more than happy to sell it.

Kinds of stone to carve

From the softest to the hardest;
1)Soapstone Available in many different colors and textures. Polishes to a smooth finish and scratches leave a white mark which makes it easy to texture.
2)Alabaster-I recommend this as a starting stone both because it is easy to carve and because it is extremely beautiful. It can bruise, but it's worth the trouble. This stone is stunning in its beauty with colors like green, red, white, gold, cream and just about everything in between. It often has internal grains that add to the beauty but increases the breakage factor.
3)Limestone (Oolitic from central Indiana is very good) This stone does not polish well but is one of the best stones for showing details carved into it, one of my favorites.
4)Marble (Colorado or Italian Carrara are two of the easiest to work with) I believe that every stone sculptor wants to try this stone at least once, to experience the stone of the masters. Its well worth the work involved to shape it but it does help to have a good set of tools since it is a harder stone.
5)Granite Good luck, needs specialized power tools and a lot of sweat, (recommended only for advanced carvers). There are others but these are the most common and useful.

Tools

These are available from a number of resources and I have listed some (Check the internet for more). A good set of starter tools are going to cost somewhere around one hundred dollars. This will include a mallet, about seven chisels, and a set of stone rasps (rifflers). My first seven pieces were made with one of these sets. My tool inventory has grown a bit now. Here are some of them.
stone carving and sculpture tools As you can see it is easy to accrue many different tools but you really don't need this many to start. In the picture you'll see a combination of different mallets, straight, toothed or rounded chisels, and a couple of files (to sound professional call them rifflers).

Sandbags

  • You MUST have sandbags before you start carving to support your stone on while carving. This takes out the vibrations in the stone as you hit it and really is necessary to prevent breakage. I make mine from old work pants. I cut the legs off and cut them in half and turn them inside out. I then sew up one end completely and sew the other end leaving about a two inch opening. I then pull the bag right side out through the opening and fill the bag loosely with white pool filter sand (beach sand tend to sift dirt out through the fabric and get the stone dirty). You can get four out of a pair of pants which should be enough.
  • For a really large stone you can build a shallow frame and pour in a layer of sand for the stone to sit on.

Personal protection

These are the most important sculpting supplies there are.
  • Goggles or safety glasses are obtained at your local hardware store. Wrap around goggles offer the best protection against dust and flying chips. It's hard to carve if you can't see.
  • Hearing protectors will help insure that you will be able to hear your grandchildren and birds later on.
  • Leather gloves will do a lot when you're tired and miss that chisel.

The hows and whys of carving.

I finished the first seven of my works without ever reading about stone carving. However I did get instructions from professor, artist, mentor and friend, Bill Kolok. Therefore I attribute all information here that I did not learn by trial and error, to him.
stone tools These are what the different basic chisels look like in a starter set. I have shown them in the order you will probably use them along with a riffler and a file.
ROUGH OUT If I don't have an idea of what I want the piece to look like I just start carving. This can be the hardest way to go since you don't know where you're going with it. You can make it easier by giving yourself a "quick start". Take a drill with a masonry bit and drill a couple of holes in it. Then build your shapes around the holes. You'll be amazed how that will help to give you a starting point.
carving limestone If I know what I'm going to carve, I usually start out by making a rough drawing of my idea. Then I find a piece of stone that fits the design as close as possible. The reason for this is you want to keep the amount of stone to be removed to a minimum. I make a drawing on the stone itself and rough it out. Do not use a marker or pen with any kind of ink in it. I did this on one of my sculptures and it bled several centimeters into the stone. If you cannot remove a lot of stone you'll have a permanent smear to explain to your viewing public (mine is blue). Use pencil or crayon.
The first step is roughing out the stone. This is where the majority of the stone is removed and is done with a heavy chisel made for removing large amounts of stone or with power tools such as a circular saw with a masonry blade on it or an angle grinder with a diamond stone cutting blade on it. A word of caution here, wear safety glasses, dust mask and hearing protectors. These are a necessity and can be gotten at minimum cost at most hardware stores. Don't try to slice off big chunks out of the stone. Instead make several cuts with the power tool into the stone to make a series of grooves leaving small slices (maybe 1/2in. thick) of stone in between. These are easily removed without fear of damaging the rest of the stone as can happen with beating it to take off a big chunk. Now that the outline of the piece is developed we go to the point chisel.

The point chisel is held about a 45 degree angle to the stone. This will vary according to the hardness of the stone. The harder the stone, the steeper the angle has to be. Don't try to take out too much stone at a time. The object here is to make a line in stone with the first pass. Successive passes will make the line deeper. Make additional lines about 1 to 1.5 inches apart. Then make more lines in a crosshatch pattern. This leaves squares of stone that can be easily knocked off with a chisel. As you make the lines and remove stone it should start to take on a shape.

Don't just follow the contours of the stone since all that will happen is the stone will get smaller and smaller. Instead try to accentuate the stone. Make the low points a lot lower while leaving the high points high. I have observed in the art classes I attended that this is very hard for some people to do. Do not be afraid to go for it. It is only a rock UNTIL you shape it. After the rough shape has emerged you use the next chisel (called a claw chisel) to further refine the shape and to remove the lines left by the point. This is where you start to get excited, things are taking shape.

Once you have removed the lines left by the point and have roughed out the shape using the claw you can use the toothed chisel to remove the lines left by the claw. See what's happening? Each step is designed to further smooth the stone. For marble it is very important to follow these steps. For the softer stones such as soapstone you may skip back and forth as seems best. For example, I do not like using the claw on soapstone and go from the point right to the toothed.

Now the flat chisel comes into play. This is the chisel that will save you a lot of work later if done right. The flat chisel is used to remove the lines of the toothed chisel ONLY. If you try to remove stone with it you will chip off pieces and the surface will not be smooth (This can be a desirable effect if you want to texture a softer stone this way, experiment on a scrap piece to see what happens).

The reason this chisel will save you work is because the next tool to use is a rasp or a riffler. These are used to smooth out the final chisel marks and to carve out fine detail that the chisels are too course for. They are not for removing mass amounts of stone although inexperienced carvers often use them this way. These tools are designed to work in one direction only (forwards) and a "seesaw action" will only wear you out and cause your tool to dull prematurely.

Next comes the file. One of my favorites is available at any hardware stone as a wood rasp. It has course and rough, flat and rounded sides. I have worn a couple of them out but they are inexpensive and one of my favorites. Use the file to (again) remove the rasp or riffler marks.

At this time you may see some white spots in the stone. These may be bruises and can only be removed by chiseling or rasping deeper into the stone, which may change the shape. Its better to be careful while chiseling to avoid them.

Sanding

Now comes the lousy part, sanding. This can take quite a bit of time but don't give up. The results will be worth it.

Start with a course grade (100 grit) of a silicon carbide (wet and dry) sandpaper, diamond paper is best but it is about $30.00 a sheet. Next in order go to 150 grit, 200 grit, 300 grit, 400 grit..... until its the smoothness you desire. I have gone up to 1600 grit to get the desired finished. Sometimes a high gloss is not what looks the best so experiment and see what happens. When sanding make sure you remove all scratches left by the previous paper or when you go to the next finer grit you may not be able to (or at the very least it will take much more work). Once you get to the 200 grit (with soapstone you'll have to start around 150 grit) it is best to use wet sanding. Get a shallow pan of water, dip the paper in it (you have to have waterproof sandpaper) and sand. As the paper gets clogged wash it and the stone off and repeat. The water keeps the paper from clogging up. Change the water frequently and always when you go to a finer grit since the water will contain the courser grit and will keep scratching the stone.

Another plus to the water is that it will give you an idea of what the stone will look like when polished.

How about those hard to reach places?

Polishing

There are going to be places that you can't reach easily with your hands. What I do is take a small dowel rod and trim it down where there is a flat, chisel like end on it. I then cut small strips of sandpaper which I loop over the end of the rod. By holding each end of the strip I can keep it in place while I sand. Remember that you'll be sanding with a much smaller area so you'll have to dip it in the water much more often to keep it from getting clogged.

I have found that 3M paper does very well with this kind of strain on it. I have tried others but they didn't hold up as well. Now that the sanding is done there is a number of steps you can take. Some people buy a rouge which is available through some of the suppliers I have listed and use a buffing wheel on a drill to apply it. If you do this, keep that wheel separate from your final buffing wheel. After the sanding make sure the stone is thoroughly dry. Some stones dry quickly and some like limestone can take a day or two. You can then apply a wax, also available through suppliers or use a floor wax made from carnauba wax. This is a hard wax and seems to do well. Rub it with your fingers until some of it melts on them and then rub it into the stone. Try to rub it hard enough to warm the stone to allow the wax to penetrate. If the stone is cold (and small enough) you may put it in a oven on warm. Don't cook it, just warm it. After applying the wax buff it with a buffing wheel (guess where you get that from?) or hand buff it with a lint free cloth (cloth diapers work well for this). Be careful when using power buffers, you don't want to press too hard. A light pressure is fine and be sure to keep moving it around, don't hold it in one place. I get great pleasure in hand buffing if I have the time. There is something about feeling the stone warm up in your hands and seeing the shine come out as you work.

Limestone can be installed outside with no wax, but if you leave it inside and desire to wax it only one brand of wax that I have found will work well. It is available only though art suppliers. The brand name is Akemi stone polishing fluid 2012. This is a liquid that you wipe on and then buff. Works well on many stones but make sure you have adequate ventilation when using it as the fumes are bad while drying.

Marble takes an additional step. After sanding and rouge (if used) you have to seal the surface. This is done either with oxalic acid (order it from the local drug stone) or with tin oxide (availible from art suppliers). I use the acid. Dissolve it warm water until no more will dissolve. Use something like a rough piece of felt and rub the surface with it WEAR GLOVES AND GLASSES, this is an acid that will attack organic matter including your skin or eyes. It literally melts the surface crystals together to seal the marble. Wash off after a few minutes with water, let dry completely, then use the wax of your choice. Tin oxide also works but it takes a lot of rubbing to achieve the same effect. Save your sweat for later.

Mounting your masterpiece

  • Not all sculptures require a base. If you decide to mount your piece, it is best worked on before you are completely finished with sanding as it requires handling and drilling the stone. When you get the stone firmly shaped out and decide how you want it to stand, you will have to decide what kind of base to mount it on. Some people go with a basic square or rectangular base. These are fine but I feel that a base must complement the sculpture without drawing attention to it and have spent many worrisome hours deciding on the best one.

    Mediums for bases

  • You can use any material that is solid enough to support your sculpture. Wood is one of the easiest to use while stone and metal are also favorites. Ready made stone bases may be purchased from most of the suppliers that I have listed below. Metal ones can be made if you are handy with a welder or pay a machine shop to make it. I hate paying more for a base than the stone costs so I make mine from wood.
  • When you have the base shaped out, position the stone on it and mark around the stone on the base with a pencil. Never use a magic marker or similar tool with inks or dyes in them. I did this once and found out that the color had bled several centimeters into the stone. I could not remove enough stone at that place so there is a permanent blue smear. Use a crayon or a pencil.
    carving tool Drill a hole (or holes if the sculpture is big enough) in the base of the sculpture. I use a tool purchased from Sears for this. It is a small portable device and your drill (3/8in. without the chuck attached) mounts to the top of it and the chuck is mounted underneath. You set the tool's base flat on the stone and it makes sure you drill it straight. If the base of the stone is too small you can attach a piece of wood with a hole for the bit in it, to the tool. This will let it set on a smaller area than the manufacturer provided for. After the hole is in the stone, position a piece of paper on it. Mark the outline of the stone and punch out the holes. Put this paper on the base, line up the outlines and mark the position of the holes. Using the drill tool, drill out the holes in the base. This will ensure proper alignment of the holes.
  • For a small sculpture you can use a 3/8in. wooden dowel. Cut it to fit in the holes and epoxy it in. I have come to favor metal studs for a number of reasons. They are strong and I can use nuts to hold the base on. A couple of times I have changed the base that I first used. Cutting off a base and drilling out the stud is a pain. What I do now is after the holes are drilled in the base I flip it over and with a 3/4in. wood bit I drill down about 1/2in. This creates a space in the bottom that allows me to install a washer and nut on the stud. Much like trophies are mounted. I buy the studs at a hardware store, the treads also help to give the epoxy something to hold to in the stone. Make sure you clean the hole of all stone dust before you glue it.
  • Colors for the base are up to you but generally I have found that a light colored base for dark sculptures and dark bases for light colored sculptures work best. Remember the color of the base should show off the sculpture, not draw attention from it.

Tips on carving different stones

Alabaster

One of the things that make it beautiful is the fault lines in it. This also makes it a stone that's easy to fracture. Before starting on a piece or shortly after you have it roughed out, wet the stone and locate these lines. They will appear as boundaries between different colors or as changes it the texture of the stone itself. Once you locate these, treat them gently. Carve with the grain instead of against them. This keeps you from actually knocking them apart. If the texture of the stone looks different (like crystals in the stone) you can bet it won't take much to break it, so you can go to grinders, files or whatever just so long as there is no impact on it. Next, you might use a different chisel. I have found that on alabaster a thin two-toothed claw chisel works best. Why? Simply because the force of the impact is concentrated on a very small area and with less stone to remove and with more force being imparted to it, the force will dissipate in the removed stone instead of being transferred to the main body of the stone where it causes vibrations that will weaken it.

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