Working Floor 1500 x 1500 mm Year 1991 Turin collection at buyer's expense 

### How a Stone Works

A stone grinder is a machine tool used for grinding and finishing flat surfaces with high precision. Here are the main components and how a lapidello works:

1. **Spindle**: Mounts the abrasive wheel and rotates it at high speed.
2. **Table**: Supports the workpiece and can move back and forth under the grinding wheel.
3. **Abrasive wheel**: The active part of the machine, which grinds the piece.
4. **Feed system**: Allows controlled movement of the table and grinding wheel to precisely grind the workpiece.
5. **Cooling system**: Used to cool the grinding wheel and the workpiece during processing, preventing overheating and improving the quality of the finish.

During the operation, the workpiece is fixed on the table. The abrasive wheel, mounted on the spindle, rotates at high speed and is brought into contact with the workpiece. The table moves back and forth under the wheel as the wheel slowly advances across the workpiece to remove material and create a smooth, precise surface.

### Types of Stones

1. **Tangential stone**: The grinding wheel moves horizontally with respect to the surface of the piece.
It is the most common and versatile type, used for a wide range of surface grinding applications. 2. **Vertical stone**: The grinding wheel moves vertically with respect to the surface of the piece.
Used for specific applications where precise vertical control is required. 3. **Rotary stone grinder**: The table on which the piece is mounted rotates under a fixed or mobile grinding wheel.
Ideal for circular-shaped pieces or for processes where a uniform finish across the entire surface is required. 4. **Double disc stone**: Uses two abrasive wheels mounted on both sides of the workpiece. Used to grind both sides of the workpiece at the same time, increasing machining efficiency.

### Why it is better to buy a used stone

1. **Cost Savings**: A new stone can be very expensive.
Buying a used model saves a significant amount of money. 2. **Reduced depreciation**: Used machine tools have already suffered most of the initial depreciation, so their value remains more stable over time.
3. **Durability**: The lapidelli are built to last over time.
A well-maintained model can continue to function effectively for many years. 4. **Access to high-quality models**: You can afford high-end models that may be out of your budget if purchased new.
5. **Immediate availability**: Used lapidels are often available immediately, with no waiting time for production or delivery.
6. **Sustainability**: Buying used is an ecological choice, reducing waste and promoting a more sustainable use of resources.

### Considerations for Purchasing a Used Lapidello

- **Machine condition**: Check the general condition of the stone grinder, including the spindle, abrasive wheels, feed system and refrigeration system.
- **Usage history**: Ask about previous use and maintenance performed.
- **Precision and tolerances**: Make sure the stone maintains the tolerances required for your work.
- **Accessories and tools included**: Check if the lapido is sold with all the original equipment and accessories or if some are missing.
- **Brand and Model**: Some brands and models are known for their durability and ease of repair. Research the available models and prefer those with a good reputation.

Buying a used lapidary machine can be an advantageous choice, allowing you to obtain a high quality machine at a reduced price and contributing to greater environmental sustainability.