Tips for Carving Monumental Stone
(i.e. Granite) Home
The following describes some of the equipment, tools and
techniques I utilize to carve monumental stone (granite and dolomite)
sculpture. Remember these are the
methods that work best for me in my applications. They may or may not apply to the way you
With respect to carving granite, don’t be afraid to tackle a
project in this material just because it is hard. You may want to experiment
with small pieces before moving up to monumental sculpture. This will help you
to develop your working techniques and self confidence. Personally enjoy the resistance and response
of granite. It is a great material to
work in. I normally carve field stone
(granite & dolomite) mainly because of it’s availability in my part of the
world. It can be very
interesting/surprising to deal with due to its impurities and faults. If you have an opportunity to carve good
quality quarried stone, enjoy.
The picture below shows the two saws I mainly utilize for
monumental work. On the yellow grinder I
run a 9” blade whereas on the green grinder I run a 4.5” to 5” blade. I use the 5” grinder for more detailed work
and the 9” grinder for roughing.
With respect to the larger 9” saw (yellow unit) this is a
basic industrial grinder. It is not
specifically a stone saw. You may wish
to purchase a unit that is specifically rated for stone. To date I have not done so due to initial
cost and functional factors. The 9”
grinder I am currently using is a Dewalt Model D28499 and meets all my requirements
at this time. The 5” grinder is a Bosh
1348. Again these are my current
preferences and you will need to investigate what fits your needs.
Things to consider
when purchasing as saw:
- RPM - for the 9” saw do not exceed
6000 rpm. 9” blades are normally
rated at 6000 rpm maximum. If you
are using blades with a lower maximum rpm rating then you will have to
purchase a saw rpm rating accordingly.
- Locked trigger – I have noticed
some European grinders have removed this feature for safety reasons. For me it is necessary to lock the saw
on due to the length of time it takes to complete a cut. Yes this is a dangerous situation, so
caution must be exercised. I can
guarantee you will jamb the blade at some time (more often when 1st
using this tool). When this happens
you have to be ready to stall the saw, so be ready to hang on. What this really means is that you must
be constantly aware and be ready for a jammed/locked blade situation. This is probably the most dangerous part
of using a diamond stone saw freehand.
If you are not comfortable
with locking your saw on or do not have sufficient strength to stall your
saw, then I would recommend that you DO NOT lock the saw on. Again
this is a personal working preference.
- Weight – Saws come in various weights. A few ounces can make a significant
difference when working long hours.
My current unit is heavier than previous units, but I have found
that the extra weight to be a benefit when cutting. That is I use the weight to my
advantage. In the end this is a
personal preference that will vary in regard to your application and work
- Brushes: - Make sure the brushes
can be inspected and removed easily and quickly. This will help facilitate the frequent
checking of brushes. When I am
running a dry diamond blade (which is the majority of the time) I check
the brushes once a week for wear.
Some grinders incorporate a feature that automatically stops the
grinder when the brushes reach end of life. I would still recommend pulling the
brushes once a week since this helps facilitate cleaning the brush holder
which could cause brush hang up, resulting in premature motor commutator
- Softstart: - A nice feature but
not necessary. I have owned
grinders that start with a jerk and I don’t particularly like this since
in my opinion it is hard on the drive gear train when running a 9” blade
and also causes the saw to jump in your hands. The unit I currently use doesn’t have a
softstart feature but starts gently.
Therefore you may want to actually try the unit out with a 9” blade
attached before purchasing.
- Handle Length: - The total length
from the front to the back handle is important. Get the longest length you
can find. I have found the longer
the length the higher the cost of the unit. Why is length important – because it
gives you extra leverage on a blade jam?
- Rotating Rear Handle – The unit I
have has a back handle than can be rotated 360 degrees at the press of a
release switch which is built into the handle. Notice the current position of the
handle. Grinders with fixed handles
point to the side instead of to the bottom. This is very uncomfortable with extended
use. Also the rotating handle is
useful when you need to reposition it for specific cuts. Normally I leave it in the current position. If you cut left handed you would adjust
it to the up position and the front handle would be placed on the other
- Blade Guard – The blade guard
should have a built in quick release mechanism, so you can quickly adjust
the guard position. I find this
useful to achieve maximum safety, viewability and dust dispersal
- Cutting: Cut from the top down rather than across
whenever possible. It will save
your back and saw blades. When
cutting vertically the blade will wear more evenly on the sides. As a novice expect to go through more
blades. It takes some time to get used to handling the saw. The deeper the cut will allow you to
increase the spread of the kerf cuts.
This means less cutting of kerfs.
I try to cut at least 2 inches deep and 2 inches wide for roughing
purposes. As you get closer to
finishing reduce the depth and width accordingly.
- Daily Maintenance - The unit
should be cleaned with compressed air daily to remove dust that passes
into the unit. Blowing the unit out
will prolong the life of the brushes and internal electrics by reducing
wear and heat buildup. With my
current unit I can quickly remove the brush covers and blow out the brush
area daily. Run the unit after applying compressed air. This should remove
more loose debris.
- Granite or Marble Blades: -
Purchase a true granite or marble blade.
For my 9” blades I do not use concrete blades since there matrix is
not designed for cutting granite or marble. You can try cheaper blades on granite –
some work – some don’t. For safety
sake check the segments for cracks daily as indicated below – especially
when cutting curves or jamming the blade.
- Dry Cutting Blades: - I use dry
cutting blades since I do not have water where I work. Besides water is messy and also dangerous
when working with electric tools.
Therefore I cut dry and allow the wind to remove the dust from my
site. Cutting dry creates a fair
amount of dust. Also the noise
level can be quite annoying.
Therefore it is not a good idea to cut with a diamond saw in your
backyard. Your neighbors are sure
to complain. Try to find a noisy
industrial site instead.
- Blade Support – Back Plate – I run a metal blade
back plate support. It helps to
reduce the wobble or bending on the blade when your working a deep cut. It also limits the depth of the cut
since the back plate is approx. 4 inches in diameter. You do not need to use the back
plate. It is just a personal
preference of mine. Back plates can
be purchased as an option.
- Cutting: Let the blade do the cutting. Do not force the blade. It takes time to cut stone. Forcing the blade overheats the diamonds
and causes premature wear of the blade.
If the blade segments are turning blue then you are pushing the
blade to hard. When the blade is at
the end of its life do not push it since this may lead to blade/segment
failure and jamming.
- Blade Check: Check your blade daily before starting
work. Check for hairline cracks at
the major segments. If cracks
develop this can lead to failure of a segment causing break out. If the blade develops hairline cracks
throw it away. If your cutting a
lot of curves and you are not very stable with your saw or you are causing
the blade to twist , premature
failure may occur. Check, check,
- Caution: When a blade is at the end of it useful
life it will tend to bind or jamb more readily than when the blade is
sharp. If the diamonds are
basically gone and the blade jambs repeatedly for no apparent reason it is
spent – throw it away – safer to spend a few $ on a new one than get
hurt. On a jamb situation the saw
will try to eject itself from the cut groove so be constantly watchful and
hang on if this happens. You don’t
want the saw to jump out of your hands and hit you or a bystander. Do not day dream when cutting free hand
with diamond blades.
- Hearing Protection: - Cutting with
diamond saws and using a hammer/chisel is a very noisy proposition. Therefore wear excellent hearing
protection. Buy the best since you
will be wearing your hearing protection for most of the day. You will want maximum protection and
comfort. I don’t use the standard
over the head band unit. Instead I
use the unit that I can fit my hardhat over. It has a spring wire that goes around
the back of the neck and a thin nylon band (Velcro adjustable) over the
top of the head. The over the head
nylon band is so thin you will not notice it when wearing head gear.
- Eye Protection: - When I am
roughing I do not wear my glasses.
Therefore I can wear bullet or welder goggle style of safety
eyewear. This is the only safety
eyewear I have found that actually keeps flying debris out of my
eyes. Other types of eyewear (i.e.
over glasses enclosed goggles) always allow some stone to get in behind
the goggle and glasses. I find this
to be a real problem when roughing dolomite.
- Hard Hat. When roughing I wear a hard hat with a
wire screen visor. Basically this
saves the skin on my face. My hard
hat has many deep scratches in it from flying stone. It probably wouldn’t meet safety
standards anymore due to the deep cuts in the plastic.
- Stone Hammer: - I use a 3 lb.
hammer for mass removal of stone.
Last year I replaced the 10 inch handle with a 14 inch handle. This has made a huge difference in
comfort and handling. It also increases
the hitting radius to apply more force.
Buy a good quality stone hammer (best quality steel) since you will
be using it a lot and hard. I
purchased my hammer from a retired stone mason. I have used it for years and the steel
head is as good as new – no mushrooming as with cheaper hammers.
- Chisels: - I do not use carbide
tipped chisels. I found that I kept
breaking the carbide points out of the steel shank. Instead I use high quality steel
chisels. I use a 12 inch chisel for
most of the roughing and an 18 inch chisel to reach into deeper
areas. Both these chisels have a
7/8 inch flat edge for setting the line on the stone and final
takeout. I seldom use a pointed
chisel. I find the 7/8 or ¾ inch flat is more efficient for the way I
work. Also add a protective handle
to your chisel. This may mean that
you will have to find an inexpensive masonry chisel in a hardware store
and adapt it’s handle. Since
chisels come in various shank sizes you will need to find a protector that
will fit your chisel. I have found
that the protective handles are a must for the way I work. I have been sculpting stone for 20 years
now and I still manage to miss the chisel from time to time. The protector makes a huge difference
when I miss the chisel with a 3 lb. hammer at full swing. Considering I cut in all directions and
on some occasions the hammer glances of an adjacent stone, no wonder I hit
- Electrical Cords: - Purchase good
quality industrial cords. I use a
50 foot #12 wire cord. The #12 cord
reduces voltage drop and heat buildup in your electric saw, thus extending
the life of the saw.
- GFI – If you are working in wet
location or outdoors I would recommend that you utilize a GFI Ground Fault
Protectors for your electrical equipment.
Self electrocution is not a good thing.
- Coveralls: - I cover up totally
when roughing out granite or dolomite.
The flying debris can be quite nasty and I have found that full
coveralls work the best. They also
give me freedom of movement and can be air condition by wetting them
- Safety Boots: - A must since you
maybe dropping fairly substantial pieces of sharp stone ( i.e. sharp 20 lb
pieces). The leather toes of my
safety boots are cut up and torn from falling stone.
- Shin Protectors: - These metal
protectors lace onto your safety boots just above the safety toes. When roughing on scaffolds these are
definitely beneficial. For some
reason falling stone seems to find a place to land behind your steel toe
and yes it does hurt. The shin
protectors will deflect the stone making your work much more comfortable
- Wrist & Elbow Support: - If
you find your wrists or elbows are getting tired – wear expandable
supports. Wrist supports also
reduce the amount of debris cutting your wrists (especially when cutting
Hand Stone Cutting
I kerf cut a line with the diamond saw I set the edge of the stone cut
line with my hand hammer and chisel.
The 1st row is a pain but after removing the 1st
line of stone you can now easily set the line. After setting the line a couple of times
the stone should start to pop loose.
When setting the line you do need a fair amount force with the
hammer. When swinging the hammer
keep your arm at full length during the swing and reach back as far as
comfortable and swing with a smooth motion. Let the hammer do the work. Once you become proficient at swinging
the hammer the full swing motion should be become comfortable and
- Back – Save your back. I have found that cutting with the
diamond saw for long periods of time (more than one 2 foot cut) kills my
back and overheats the saw.
Therefore make one cut – put down the saw (no matter how tempting
it is to keep cutting) – pickup your hammer and chisel and remove the
latest cut material – do over. In
this way you can work for a 7 to 8 hour period quite comfortably.
- Tired – Rest – If you have been cutting with your diamond saw for a couple
of hours and find yourself physically fatigued – Stop – Take a break. Do NOT operate your diamond saw when you
are tired (beat-up) since this can lead to accidents. When I get to this stage I take a 15 to
20 minute break and lay down on a stone.
At this point the stone feels awfully comfortable and besides
messes with peoples heads when they see some fool lying on a stone.
- When working on scaffolds use high
quality stable scaffolding.
- When I
am standing on a platform that is more than 5 feet from the ground I use
an approved fall protection safety harness and tether. The tether I use is an approved seat
belt tether that will break a fall within 3 feet. You may want to opt for the bungy tether
systems. If so make sure your
purchase the correct tether arrest length for your application. The reasons (other than occupational
safety) that I wear the fall arrest equipment is that it provides me with
an added comfort level when working under windy conditions and in the
event the saw jams. Either
condition might cause me to loose my balance while working on a scaffold.
Don’t let me scare you with the safety issues. Use good common sense and things will go
And remember get some blood on the stone.
Copywrite: Floyd H.