Diamond blade coolant

[Mike from North Queensland]

As part of my fossil preparation process I have the need to reduce the size of the background rock on some specimens collected in the field.

My preferred tool is a 300mm slab saw I acquired a while back made for lapidary work as this has very little vibration.

Normally if I use it to cut agate or similar rock I use the cheap home brand baby oil, works a treat, good for the hands and no smell after.

On the test piece I did with the softer stone the oil permeated into the rock base and the fossil and cleaning in detergent straight after only got the surface clean.

I doubt the baby oil will harm the fossils but suspect it will prevent permanent gluing of damaged material and leaves and oil stain that I do not want.

I tried a second piece and painted the surface with paraloid to seal, but the cut edges still stain.

So currently I drain the coolant from the saws sump and replace with water cut the fossils and then drain the water from the sump as the water will cause the diamond blade to rust.

 

The question - does anyone know of a coolant that can be used that will not seep into the softer fossils / rock and will not rust the diamond blade?

 

Mike D'Arcy

[Ridgehiker]

I dont have an issue with rust on a diamond blade using water.  However a blade sharpens and cleans up like new in a couple seconds by making a couple passes through a concrete paving stone.  Blades are usually discarded way too soon and have lots of cutting life left. A small grinder can dress the blades on the side but I just use the concrete paver.

 

As for a fossil. I always use water. If a fossil is porous just soak it in water for a couple hours before cutting. This firms it up and prevents anything else seeping in. I've cut literally thousands of specimens over the decades and no issues.

 

The same if using a flat grinding wheel for making thin sections, acetate peels, etc.  Let the specimen absorb some water if any concern about it flaking or breaking apart.

 

As for type of oil for agate, etc. For the big stuff I like hydraulic oil. For little stuff, mineral oil.  If at all concerned about discolouration then I've used RV antifreeze but that's a product likely rare in balmy Australia.

[fossilcrazy]

Hi Mike,

Just about anything that might help lube your Diamond wheel will be able to penetrate a soft porous rock. Do you feel a non-lapidary diamond blade used to dry cut, would not work or your application?

[RJB]

Ive been using plain ole water for about 20 years.  No rust issues either.  Not sure why yours is rusting?  And like Canadawest has already said, a paving stone is great for getting your blade back in order.  Good luck

 

RB