Stone slabs for custom knife making

[alittlerockshop]

Greetings!
This is my first post on this forum.
Lately, I have been toying with the idea of making custom knives, but right now it seems so far out of reach for me.
Maybe some day when I am not spending so much time with my business, I can learn to make my own custom knives!
On the other hand, I have a somewhat successful lapidary business and cut hundreds of pounds of rock for the lapidary trade. Seeing that there are knives with custom handles made of stone, I thought that maybe some on this forum would be interested in my slabs.
We are located in Delta, Utah and do most of our business on ebay.
I deal alot in Picasso Marble, which is a great stone because of its ability to be worked easily and takes a nice Jasper-like polish. I also have quite a variety of other material such as Dinosaur Bone, Petrified Wood, Jaspers, Onyx, Obsidians, etc.
If you are into ebay, you can see some of our slabs for auction at: http://stores.ebay.com/A-Little-Rock-Shop
If you prefer not to deal with ebay, I am working on a website at (It is closed right now while I input inventory):
http://www.alittlerockshop.com
I also custom cut material for reasonable rates.
You can contact me by email at alittlerockshop@frontiernet.net.
Thank you!
Dave Barr

[SharpByCoop]

Hi Dave, and welcome to Knife Network forums!

Thanks for your post and links. I am certain many folks in here could benefit from your supplies. I am certain they could also benefit from your expertise, so maybe you can help us in more ways than one.

Thanks again.

Coop

[BigD]

Like Coop said , help , how do you drill a hole in the rock , like for pins?

[cwp]

I'll echo BigD. How do you work the Marble you're selling? Does it work on standard wood/metal working tools?

--Carl

[Messinger]

Yes, Dave - please tell us more. I am sure many of us would love to work with stone if we knew how. We need to be able to shape, drill (accurately), and polish. Is this within the reach of the typical knife maker (ie. carbide drill bits, ceramic grinding belts, buffer & elbow grease?)
-Ben

[alittlerockshop]

I wish I could be of more assistance with how to accurately use the stone with knife making. I have seen it done, but haven't done so myself.
That will probably be my next project!
I do know that anything that can be made in wood, can also be done in stone.
As far as tools, you will need to have sanders and grinders that are capable of being used in a water environment. This may have some negative effects with steel?
Stone work requires a series of sanding and grinding steps that start with a coarse grind and work to a very fine grind which is a basically a pre-polish (100 grit to about 3,000) and then a polish such as Zam for the Picasso Marble. Different types, and hardness of stone require different grinding stages and different polishes to get the right finish.
I can direct interested parties to more information on what types of machinery, etc to use for working stone.
As far as drilling holes in stone, I have put together a little set of instructions:
In order to drill small holes (under 1") into stone follow these simple instructions. The drilling process is the same whether you are working with marble, agates, jade, slabs, gemstones, or just about any other type of rock.

Note: To prevent a condition called “blow out” in your piece, which results from the pressure of the drill point breaking a circular portion of stone from the bottom of the blank just before it drills through, you can place your slabs together that you are drilling the hole(s) in with a “sacrificial” slab of hard stone, or wood on the bottom of the stack and tightly tape them together with some tape that will not come loose in water, or you can use some other form of bonding to keep them together that will not create too much pressure on the slabs and force them to break.

1. Start with a diamond drill bit. Diamond bits are the correct type of bits to use for rock work.

2. Diamond bits are meant to be kept wet. The bit doesn’t need to be in a lot of water, just enough to wash away the rock mud and keep the bit wet and cool. The easiest way to accomplish this is to do your drilling in a bin or tub of water.

Another way of keeping the stone wet is to have a drip system continually dripping water on the point you are drilling. Or, you can have someone with a spray bottle stand next to you and squirt the point of contact with water.

3. Drilling is best done in a drill press. If you tweak the bit, it snaps apart. Holding the bit perfectly perpendicular to the stone is vital.

I use a Foredom Flexshaft with a manual table-top speed control (more precise control than the foot pedal), and a foredom drill press.

Once you start drilling use a very gentle up/down motion to let fresh water under the bit. If you slam you bit back down on the rock, you will knock off the diamonds, making your bit useless.

A speed of about 4,000 RPM is recommended for a .75 mm diamond drill. As the size of the drill goes up, the speed should come down accordingly. Excessive speed keeps the water from reaching the bottom of the hole. Diamonds create ultra fine dust as they drill, so it is a must that you clear the drill quite often -- drill down a little bit and then raise the drill out of the hole, repeating this process until you are through the hole. Remember, too high of speed or not keeping the hole washed out will result in the diamond plating burning off the drill shaft.

By following these steps your bits should give you their maximum drilling capacity, and you should have nice clean holes drilled in your stone.

I hope this little bit of information helps.
Please ask more questions and I will try to find the answers!
Thanks, Dave

[Messinger]

Dave, this is EXCELLENT info! Thank you for this thread and that last very informative post. I think I see some rock in my future. I looked at your Picasso marble. Very attractive!
-Ben