Slab Saw Coolant

Hi, I just bought a used 20 inch Slab Saw and I need to replace the Oil
in it. Up until now, I only had an Eight Incher, and used Water with
a little soap. This thing holds at least 5 Gallons of oil, so I am
trying to find something that isn’t very expensive, but will still
keep me from having to replace that blade anytime soon. I have seen
"Pella Oil" discussed, but have no idea what it is, or where to get
it. Would this be the way to go price/quality for that saw? I have
also seen RV antifreeze discussed-but for smaller saws-is this an
option for me? Any advice would be appreciated on this subject. Larry
Durnings Rings & Things

Hello Larry, You are better off using pella oil (from Shell Oil)or
almag (from Texaco). They both work with hard materials. Any coolant
will work with soft stones. When you need to slice larger rock you
need something that will keep the blade cool and carry material out of
the cut. You can order oil from lapidary supply or if you are in a
larger city, order from the supplier. To cut down on expense add
bricks on the opposite side from the blade. I line up the whole right
side from front top back. Also these oils can be cleaned and reused.
Write off line and I will give you details. Steve Ramsdell

Larry -
You have lots of options for oils in a large slabbing saw: Pella is
made by Shell, Almag is made by Texaco; or you can ask your local
petroleum wholesaler for their equivalent to these. Basically you will
be getting a foodgrade oil, which means it is safe to use in food
processing hydraulic equipment. My best buy has been through a local
(upstate NY) group, and it’s what they refer to as mineral seal oil.
There is a major string on this topic in the archives at Lapidary

I’m running several saws daily, up to 20". Please let me know if I can
help you further.


Almag Oil is what I use. I forget who mmakes it (Texaco?) there is
also a newer oil more expensive, but it’s white and clear (at
least to start with) good luck gregor

Try automobile antifreeze, it’s a glycol base, great coolant,
anti-corrisive, works for me. Read about this in a '92 Rock and Gem

Steve is right. These are the best oils. Do not try soy bean oil,
which some have decided would save them a little money. It will end
up coating everything with a gummy substance after while.

Rose Alene McArthur

My choice of coolant depends on what I am cutting- I use water based
coolant for copper minerals and soft, porous stones to preserve the
color, but I have learned the hard way to use Almag oil (which I buy
at a local lapidary shop) when cutting agates, jaspers and petrified
wood. The stuff is so tough that I can easily ruin a saw blade in an
hour or less if I use water-based coolant.

Lee Einer

I don’t know about others on this list, but I would like to “hear”
what you and others have to say about this. This is an area that get
discussed at times but to date I am not too sure what to use as so
many have such different recomendations. Maybe the problem is really
what you are cutting. Agate takes a better “coolant” while jade
takes ?? but sandstone takes ??? Is there a “need” for using
different cutting fluids for different materials?

Thanks one and all.

John Dach
MidLife Crisis Enterprises
C.T. Designs
Cynthias sculptures are at:
Maiden Metals,
A small bronze foundry, no web site yet!!

Hi Larry, I recently bought an 18" Covington saw. I called Covington
and asked what they recommended, and they recommended oil as opposed
to water and oil mix. They said unless the saw is used commercially,
like every day, the oil-water solution will encourage rust. We have a
Mineral and Gem club here, and the cutting oil they use is called
something like almalgam. I think Texaco makes one also, but the
drawback to all the cutting oils is that they ‘vaporize’ or cause a
very fine mist when cutting, and they smell terrible. After
considerable research into oils, I found that a 20 weight Kosher
Food-Grade Hydraulic Oil from the local oil supplier in the yellow
pages works best. There is no smell, there is no mist or vapor, there
is no taste, it has no additives, and it cuts great. Most also have a
high flash point of 400 degrees or better. Another solution is to use a
Vegtable Oil, but I read someplace that they eventually got 'gummy’
and hard to clean up. I’ve seen that on the outside of a Corn oil
bottle in my kitchen, so I can only imagine that it would be true for
a saw also, so didnt try any of the Vegatable Oils.

Heres a link to three of the Food Grade Hydraulic Oils. There are
many more, just search in your browser for those four words. I found
mine locally from Ray-Jack (below #3) for about $8.00 a gallon and it
came in a 5 gallon pail. I bought 2 pails for the Covingtom which
takes 10 gallons.

-hope this helps

Try automobile antifreeze, it's a glycol base, great coolant,
anti-corrisive, works for me.  Read about this in a '92 Rock and

Automobile antifreeze is poisonious to your pets and the fumes are
equally bad to you. I think what you read was to use RV antifreeze
which is used in the plumbing of the living space and not used in the
engine of vehicle.

The problem here is not just the material that you are cutting, John.
A saw using a good cutting oil will last three times as long as one
that is run with water coolant.

Rose Alene McArthur

no! no! no!!!*

Do not ever use automotive anti-freeze in your saw. Unless you
have a death wish. It is poisonous!!! On the other hand, you might
want to use the anti freeze they sell for motor homes to keep their
water tank from freezing.


John - the best way to approach this is to check out the Lapidary
Digest site As with Orchid, you
can access lenghthy strings on many topics, including a huge one on
slab saw coolants. All of the issues are discussed in great detail.


Greetings: Regrettably I must seriously disagree with Mr. Weaver.
While antifreeze may well work as a saw lubricant, short of PCB there
is nothing more toxic and dangerous for your health. PLEASE DO NOT USE
ANTIFREEZE UNDER ANY CIRCUMSTANCES (caps are for emphasis not as a

Allmag and/or Pella each will do a good job.


Joe Bokor

If you are going to use antifreeze don’t use the automobile type it
is poisonous. Use the type for RV water lines. However I would not
use it at all if you will be cutting hard materials such as agate. It
is also very hard on the metals in the saw. There is no lubrication
and all of your slides and screws will tend to seize. I have tried it
and went back to Almag the cost is about twice as much but it is much
easier on the saw and your blades will last longer.

Have a Happy Easter,

Try automobile antifreeze, it's a glycol base, great coolant,
anti-corrisive, works for me.  Read about this in a '92 Rock and Gem

(and it was retracted in a later R&G!!) This is a great way to get
terminally ill! Antifreeze is toxic! This has been going round and
round on lapidary lists; the only antifreeze you may consider is that
intended for the drains of RVs. The “cheap” kind you use in your car
will kill - plus which, it doesn’t work as well as cutting oil.


    Try automobile antifreeze, it's a glycol base, great coolant,
anti-corrisive, works for me.  

G’day; it might be as well to be a little wary of anti-freeze when
used as a saw coolant. The spinning saw creates an aerosol -
microscopic particles that are so fine they float about almost like a
gas. It really isn’t a good idea to breathe this. Water is one of the
best coolants and lubricants for rock saws: oh I know some saw
manufacturers will tell you that you must use oil with their saws, and
I really can’t think why. But many lapidary suppliers sell a rust
inhibitor with which one dissolves small amounts in the saw cooling
water and this helps to inhibit the formation of rust on the saw.
After use, I dry my saw and either give it a good squirt of CRC5-56
or wipe it over with an oily cloth. And water is a lot cheaper than

As a footnote, the jade factory at Hokitika on the West Coast of the
South Island, NZ, cuts up around a ton or so of jade every couple of
days. It uses diamond saws 5 and 6 feet in diameter running day and
night to cut up the jade boulders; they have several small saws for
reducing the slabs, and they employ many men and women to carve and
fabricate the jade. None of these tools are used with oils; nothing
but water is used as a coolant and lubricant.

John Burgess; @John_Burgess2 of Mapua Nelson NZ

Dear John, With reference to your illustration of the use of water in
the jade factory for cutting large boulders of jade, I think it may
be relevant to consider the fact that not all diamond saw blades are
the same. Here in the 'States, suppliers of diamond saw blades
frequently specify whether a given blade is designed for use with
water and I strongly suspect that those that are ,have been charged
with a substantially heavier dose of diamond grit. Furthermore, the
diamond blades which are used for heavy duty applications using water
are usually slotted or perforated to enhance the cooling effect. In
the hey day of rockhounding ,impecunious lapidaries opted for cheaper
blades inasmuch as diamond abrasives were much more expensive than
they are now. Regardless of whether you use water, it is very
important that, when you do ,it is best to remove the blade from the
saw after use and thoroughly dry it, then treat it with a lubricant
so that it will not be damaged by rust. Water tends to penetrate the
crevices in the metal which bind the diamond particles in place. The
best solution is to get only the heaviest duty saw blade available.

Since no one seems to have mentioned it, I will also mention the fact
that it is always best to soak whatever rock you are sawing in water
for several days prior to sawing. In this way you will preclude the
absorbtion of oils or any other noxious coolant you are using. The
old rockhound standby, diesel oil cut with kerosene, has always been
a pain in the rear when absorbed by a porous rock and, in case you
are not aware, agates and jaspers are actually quite porous. Ron at
Mlls Gem, Los Osos, CA.

The type of antifreeze that I was referring to is Propylene Gycol
based, Not Ethylene Glycol, which is very poisonous, is absorbed
through the skin, kills pets,etc. I use it in my cars, I use it in
my saw for certain types of stones. Sorry to cause panic.