An ancient form of water cutting dates back to Roman times. They used hydraulic systems that diverted high-pressure water to carve gold out from stone.
Hydraulic mining even became popular in America during the Gold Rush of the 1850s. Miners often used it in their search for gold in frontier California.
Since then, technology has advanced and given us modern-day water cutters. In this article, we’ll cover all the basics of what a water cutter is and how it works, so keep reading!
What Are Water Cutters?
A water cutter, or waterjet, is a tool that can use a high-pressure stream of water to cut through metal parts. The water pressure ranges between 20,000 and 55,000 pounds per square inch.
The waterjet cutting process involves the spray of water getting pushed through a narrow jeweled nozzle. The spray is a high-pressure, concentrated jet. A key benefit to the water cutter is that it doesn't overheat like metal cutters do.
So long as the metal has a hardness of 8.5 or less on the Mohs’ Hardness Scale, a waterjet can cut through it.
Advantages of a Water Cutter
There are multiple advantages to using water cutters. Compared to traditional cutters such as machining, laser, plasma, EDM wire cut and more, the water cutter excels in almost every way.
1. Strongest of the Strong
It's capable of cutting through almost any material or metal, so long as its hardness doesn't exceed an 8.5 rating on the Mohs' scale.
2. Smooth Finish
When a water cutter slices through metal, it leaves behind a smooth finish. The result is like if the edges had been sanded. Most other cutting methods leave rugged or jagged bits behind.
3. Never Overheats
Most other cutting machinery can overheat. With water cutters, there is no threat of this happening. They have no heat-affected areas. Because the water cutter workpieces are water-cooled, the temperature doesn't increase by much in the cutting zone.
Another more modern reason water cutters are helpful is because they are environmentally friendly. Other cutters sometimes make use of toxic gases or liquids that require eventual waste disposal.
Water cutters have broad functionality. With other cutters, you may have to switch out certain parts to cut through a different material. Whereas a water cutter can saw, drill, profile mill, gear cut, punch, and do spline cutting and slitting.
6. Strength and Precision
Water cutters are an optimal choice in almost all categories. It's able to cut a stack of different metals up to four inches thick. It's even delicate enough to cut a material as thin as five-thousandths of an inch.
7. Cost Savings
With a water cutter, the first cut is the final finished product. There's no need to sand a surface or do small cutting adjustments.
Thanks to this process, water cutters save on material and machining costs.
Drawbacks of a Water Cutter
Nothing is perfect, and that includes the water cutter. While it has more advantages than anything, there are a few drawbacks you should know.
1. Kerf Width
Kerf is the material removed during the cutting process. With a water cutter, it's the width of the jet stream.
On average, water cutters use a jet stream width of 0.04 inches or 1 mm. This means that inner corners are incapable of being cut 100% sharp. Its radius will match that of the jet.
2. Hole Size
A water cutter cannot cut below a diameter of 0.1 inches.
Since the average kerf of a water cutter is 0.04 inches, it's difficult for the water cutter to do cuts below that. It is possible though.
When the water cutter first breaks through the material it's cutting, this is called piercing. The hole caused by piercing is rough. While the water cutter can accomplish a rudimentary hole below 0.1 inches, it will not be smooth or accurate.
3. Partial Cutting
Water cutting is best used with cutting all the way through the material. It is not best used to do partial cuts or blind cutting, where the cut stops at a certain depth.
4. Lead-In and Lead-Out
The part where the water cutter stream begins and ends its cut is called the lead-in and lead-out.
To avoid small indentations tarnishing the finished product, the lead-in is done at a part of the material considered scrap.
This is perhaps the biggest disadvantage of using a water cutter. A taper is caused by the cutting stream spreading out the further from the nozzle.
With the waterjet cutter, there are three common types of tapers: V-shaped, reverse, and barrel.
A V-shaped taper is caused by the water stream holding a higher cutting energy at the top of the cut. This creates a wider cut at the top. The faster a cut is done, the more pronounced the taper will be.
Reverse taper occurs during slow cuts or in soft materials that erode fast under the power of the water stream. Since the water stream spreads out the farther from the nozzle it travels, more material is cut from the bottom than the top.
A barrel taper is more rare and happens when the material is especially thick.
Water Cutters Are More Useful Than You Know
Water cutters in some form or another have been around since ancient times.
In the modern age, water cutters have helped us achieve many great things. It was once used to rescue Baby Jessica from the well in 1987. Did you know waterjets are even used to cut candy bars?
Water cutters are a part of human history and have held an important part in shaping our civilization. From mining gold to shaping marble and more, water cutters aided us in achieving our goals. Who knows what future uses we’ll adapt the water cutter for. We hope this guide proved useful in answering all your questions about water cutters. If you enjoyed what you read, please look around the site and see what else we have to offer.