---Thread Files---

Trim Saw Lubricants

The numbers at the beginning of each message refer to the Issue number and the message number. Thus, 73-5 is the fifth message in Digest Issue #75. The name in parentheses at the end is the actual file name of this thread file in the Archives


My husband & I are new to lapidary but we bought an old but serviceable Lortone 8" trim saw. I am a jeweler so I want a wide range of rocks cut to design with. Right now we are cutting with oil and it is Soooo messy and stinky plus you can't see what you are doing because it coats the plastic shield so much. At shows and in Lapidary Journal I've seen things like "Lube Cool." I like the benefits they list, but what's the down side?

We will cut things from boulder opal to jasper to granite and basalt. Then we'll cut nothing for a few weeks. What are all your thoughts on using water plus additives in your saw?



Most of the water based coolants have a down side... if left in the saw, rust builds up on the metal parts.

Does anyone know of a non oil-based coolant which can be left in the saw without the rust problem?


I enjoy the products made by Universal Photonics, in Hicksville, NY. If you order products from them please let them know you heard about them from Thom Lane, the lapidary in Gloucester. They have an interesting catalog and supply the optical grinding trade (quartz lenses), rather than the lapidary trade. Their products are therefore aimed at a professional market rather than a 'hobby' market.

I recommend their Rhodes DiaKool water soluble oil. It will, however, attack certain metals and you may find some parts of your saw corroding badly. Whether the other water soluble oils have this problem I don't know. They only sell 5 gallons at a time and, as you mix it 20/1 you will probably want to share this purchase between several cutters.
Best regards,
Please see my website at http://www/shore.net/~lanelap/
(Ed.Note: I could not find a web site for Universal Photonics but I did find an address if anyone wishes to contact them: Universal Photonics, Inc., 495 W. John St., Hicksville, NY 11801-1014 ;Phone: 516/935-4000 ;Fax: 516/935-4039 ;Contact: Neil Johnson. Before I used their Diakool, I would want to know more about which metals it will corrode badly! hale)

Although I am new to lapidary, I too started out with oil and switched to waterbased coolant/lube because I had turquoise to cut and had read in several places that oil should never be used to cut turquoise. I am using LUBE COOL 4800 and it is working very well, but I also got some bags of CRYSTAL CUT to use next for economic reasons. There is an article in June 1997 Rock & Gem by Dale Hileman that covers the subject very well.

LUBE COOL 4800 was $10.50 for a pint and I am very satisfied with the results, but here in Hemet evaporation is a big problem. Heck the ink even evaporates out of my ink-jet printer faster than I can keep filling it. LUBE COOL 4800 is diluted 10 to 1 for cutting, and in less than a month I've used half the pint.

I heard of CRYSTAL CUT from Mr. Hileman's article and it goes for about $5.25 a pound with a dilution of an ounce per gallon, and that comes to about 33 cents. Nothing can match oil and kerosene for blade life and cutting speed, but water-based coolant is what I intend to stay with.

On the minus side is (more frequient) saw dressing by cutting a piece of red brick when the saw "dulls" - the red brick exposes the diamond particles. Also, waterbased coolant evaporates quickly, but so does kerosene.

On the plus though is that waterbase coolants are (for the most part) safer from an environmental standpoint as well as being non-flamable and cleaner to work with. Your slabs won't need to be soaked in DAWN detergent to get the oil out of the pores - a simple rinse will leave them dop-able.

Jerry Mings / Rich Balding
Wizard Home Page: http://www.net-quest.com/~wizard/

The second item in Issue 37 (Digest37.txt in the Archives) is a paper by Bill Ritter, President of Contempo Lapidary, on reasons saw blades won't cut. His information comes from several makers of diamond blades. His second paragraph summarizes it all:

"Nobody likes the smell of diesel or kerosene (which many old-timers use, and we stress DO NOT USE!) and the trouble of clean up and disposal of the sludge. But for cutting hard stones like quartz-based stones (agate, jasper, petrified wood, etc.), oil is the only cutting fluid."

Note that he is ONLY talking about cutting hard stones, such as quartz. He then says:

"We or our friends have tried about all the water-based coolants available and we have not found one that does not "glaze over" the saw blade. Basically what happens is that the water does not really lubricate, and at the point of
contact between the blade and the material, it gets so hot that there is a micro flow of the metal bonding material over the diamond. Once this happens, the metal starts to ride on the material and the diamonds are no longer exposed. Then the blade stops cutting. It's that simple."

So paraphrasing the above, his recommendation is: If you cut
Quartz-like stones, use oil to extend blade life. (I guess
the flip side of this is - if you don't care about blade
life, then use any coolant you want on any stone you cut.)

But what if you are cutting soft stones? He says:

"For soft stones like marble, travertine, turquoise, or even granite, you can use the water soluble coolants, as these stones are abrasive and clean the blade, and do not produce as much heat when cutting as the quartz type stones. Also, you will not impregnate the porous stones with oil. But remember, when you use water, even though it has a rust inhibitor in it, you should drain the saw every night and wipe it down and spray something like WD-40 on it to prevent rust."

This is pretty clear: water+additive is OK for cutting softer stones, but daily cleanup is required to prevent rust. And by daily cleanup, for me, it means doing exactly what he said: empty the fluid, wipe dry, and spray metal parts with a rust inhibiting oil.

If this is a topic of special interest to you, you should get and read his whole paper; it is in the Archives with the name: MySawDoesntCut.txt. I have copied and quoted only three paragraphs from it, but I believe these three paragraphs answer most of the questions asked in the query. He also
discusses qualities of a good cutting oil, and other topics of sawing interest.

Hale Sweeny

I use RV coolant in my trim saws up to 10". NOT THE AUTO ANTIFREEZE!!! It has alcohol that is absorbed directly through the skin,and is TOXIC!! The PINK stuff does not. Again, do not use the yellowish auto coolant, use the pink RV coolant.

Everything washes up with water when you do. Saws run at slower speeds and with blades larger than 10" will run well in diesel fuel. It has a fairly low flash point and does not usually ignite. However,there are exceptions to everything, and I would recommend saws always be monitored when cutting.


"non-commercial republish permission granted"
(Ed. note: The material Frank refers to is Dowfrost RV from Dow Chemical Company. He said, in personal correspondence, "All I've ever seen has been pink, guess it could come in other colors. States right on the label that it is odorless, tasteless,and contains no alcohol. Want to get technical??
It has a "propylene glycol base" ! I use it full strength because it cost about $3.50-$4.00 per gallon (even less on sale) and my trim saws don't hold that much." Thanks, Frank. hale)

I tried several saw oils years ago and either the smell or the reaction to the skin curled me...I nearly decided to buy preforms only. Then, through research in old magazines I came across a reference to Shell Oil Co.'s Pella A.

It is hard to find and available in 55 gal. drums and sometimes in 5 Gal. pails. Finally I found a product that I could live with. I have used this oil in all of my saws--24" down to 4". As it was explained to me by a rep. at an oil wholesaler, the Pella A is one extract away from "baker's lubricant" (used to lubricate the paddles in large commercial dough making machines). It is colorless and odorless, cuts cool and clean (nearly as good as motor oil & kerosene mixture) and has a high flash point.It mists very little, does not react to the skin, and basically resembles water, except that it does not rust metal. Also, it cleans from the stone with an overnight journey into the UNsented, cheap, generic "cat litter". I've never used it on porous rock, butwould not recommend it...it is oil.

For stones like turquoise, I use water and throw out after use.

Footnote for a rock that stopped cutting: the last time it happened to me, I took it out of the vise and made a couple of cuts with an old 220 grit silicon wheel. The blade worked wonders after that! And after a hundred cuts or so (18" saw), when it "sounded" like it was laboring, I sharpened the blade again...your saw will talk to you if you listen to it long enough.

Brewster McShaad
Riverside, CA
You can use this info freely.
(Ed. Note: There are several good oils designed specifically for use in rock saws; Brewster uses Pella A by Shell Oil. Another is AlMag by Texaco, and still another is Finecut by Contempo Lapidary.

The lubricating division of Shell Oil has an e-mail address for technical questions, but I can't find it now, but will publish it when I find it. Shell Canada's address is lube@shell.ca

Texico's e-mail address is asktic@texaco.com and their 800 number is <800-782-7852 Option 4>


I have been following the thread on saw coolant with interest. Most of the suggestions have merit and will work well. The original question of what to use in a small trim saw (4-6 inches) has been somewhat lost. The key word here is "trim". Small material, usually already slabbed, is the stuff being cut. Any of the water based additives on the market will work well. Lube Cool, Crystal Cut and DiaCut when mixed with water are essentially odorless and stain free. All contain a rust inhibitor ( not rust proof)additives as well as surfactants and organic lubricants.

On larger saws (8 inch plus) there are several very good oils. We distribute Shell Pella A, others are Texaco Almag and the Contempo product. Using diesel fuel, kerosene and forms of antifreeze is downright dangerous. Being poisoned or blown up is not my idea of pursuing a hobby. A classic case of pennywise and pound foolish!

The key to good performance with a trim saw is matching the blade to the job. Expecting a .004 or .006 blade to last as long as a .012 or .025 for all trim chores is unrealistic. Blades specifically made for water based coolants are available (Lapcraft DiaLaser, Star Sunburst).

Peter Erdo
Graves Company

In the San Francisco East Bay Area Pella is available at:

Golden Gate Petroleum
1565 Industrial Pkwy West
Hayward CA (510)783-6500

It is available in 5 gal. containers although the last time I picked up 20 gallons they had to fill some from their 55 gallon drum. I don't think they carry a large supply so it probably would be safer to call ahead. I paid $5.64 per gallon in April 1997.

I have used this oil for over twenty years and have had good luck with it. I don't think I would call it "odor or mist free" but it is better than anything else I have used. I still add a mist killer to my small saws and cut with a respirator and rubber gloves.

The responses on slab saws binding probably gave the correct answer but I had different problem once that gave the same symptoms. I had about a year's use on a 20" saw blade when it started cutting a curve and binding. After a lot of measurements with no results I reversed the blade and the problem went away. I have never had the problem again so I can only guess that something I had cut had dulled one side of the blade more than the other but I can't say I am happy with that explanation.

Dick Friesen
(Hale's Note: From the Internet: "Those needing technical information on Shell products and lubrication can call the Product Information Center from 7:00 AM to 5:00 PM central time Monday through Friday: (800)-231-6950."

From their web site:"Shell PELLA® Oils are versatile, low viscosity, "mineral seal" oils with relatively high flash points. It is named 'Pella-A' east of the Rocky Mountains." They sent the following table for you techies:

Typical Properties of Shell Pella Oils

ASTM Pella Pella A
Method (w.of Rockies) (e.of Rockies)
Product Code 61906 61900
@ 40?C cSt D 445 6.1 4.3
Gravity, API @ 60?F D 1298 30.9 41.2
Pour Point, ?F D 97 -50 30
Flash Point, COC,?F D 92 265 265
Flash Point, PMCC,?F D 93 255 255
Aniline Point, ?F D 611 175 188
CU Corrosion @ 212?F D 130 1 1
Sulfur, %w D 2622 0.06 0.06

As an aside, the phone numbers or e-mail addresses of technical info departments of large corporations are easily found- just go to the internet and do a search with any of the search engines. I personally prefer Alta Vista. hale)
end (TrimSawLubricant.txt)