So, you did it, you’ve designed something fantastic, and you want to turn it into something you can hold in your hands. Pat yourself on the back because the hard part is over! Sort of. Now you have to decide how you’ll turn your CAD design into a physical part. You know that the best options for your work are laser cutting and waterjet cutting, but you aren’t sure which of these will be best for your project.
The good news is, we can help! Let’s take a closer look at each of these services and narrow down what’s best for your project, how much they cost, and how fast they can get your parts to you.
Understanding Cutting Service Applications
Before you do anything, it’s essential to understand each type of cutting’s pros and cons and which one will be the best fit for your project.
As we go over general concepts, these are some things to keep in mind when shopping around:
- The material type you’ll need (steel, aluminum, brass, wood)
- Required accuracy and tolerance
- The thickness of that material
This is by no means a comprehensive list. When you start tackling more advanced designs and projects, there’ll be plenty of other factors to consider. For now, let’s start with the basics, and we can get more in-depth later.
Waterjet: Applicable Materials
Suppose you’re not familiar with waterjet cutting. In that case, it is the process of using highly pressurized streams of water, usually (but not always) mixed with abrasives, to cut material.
Types of metals suited to waterjet cutting are:
- Metals- brass, carbon steel, tool steel, aluminum, copper, titanium, and more
- Natural Materials- glass, leather, stone, marble, granite, and more
- Composites- fiberglass, kevlar, carbon fiber, and more
- Rubbers and Plastics- foams, polycarbonate, and more
It’s important to note that while these materials are suitable for waterjet cutting, they have their conditions.
For example, most steels are good candidates for waterjet, but steel thicker than about 1” is ideal. This is because waterjet is much better at processing thick materials that lasers may not be able to cut at all. Below 1” in thickness, lasers are much faster and will deliver significant cost savings.
Back on the subject of thickness, waterjet cutting is fantastic for many thicker materials. The broad range of thickness that is acceptable for this method is about 0.125”- 12”. Projects less than 8” in thickness are most common.
Be sure that the material you want is suitable for waterjet cutting before starting down any production paths. For example, anything that might not mix well with water won’t be a good fit: paper, cardboard, materials that can develop rust, etc.
Laser: Applicable Materials
Laser cutting is pretty easy to talk about since it’s a relatively simple process (to explain anyway). A powerful laser beam is focused on a single point about the thickness of a human hair, generating enough heat to cause the material to vaporize.
These types of materials are well-suited to laser:
- Metals- brass, carbon steel, tool steel, aluminum, copper, stainless steel, steel alloys, titanium, and more
- Natural Materials- wood, paper, cardboard, cork, and more
- Rubbers and Plastics- acrylics, foams, POM, PMMA, Lucite, and more
As with waterjet cutting, you must first consider if the material is suitable for this method.
For example, laser cutting is not well-suited for highly reflective surfaces (such as copper more than ¼” thick), as the semi-molten material can become highly reflective and bounce the beam to unexpected places (like the wall across the shop). Regarding thickness, you’ll find that applications best suited for this method are materials under ¾” thick, but it is still possible to cut materials up to about 1” in thickness.
Okay, cool, so we’ve got a little more information about the applications of these cutting services, and in terms of application, they can be pretty similar. After all, the entire idea is to cut some material. Let’s move on to what really separates waterjet cutting from laser cutting.
Unpacking Precision and Speed
You’ve heard the adage: Quality, speed, price. Pick two.
Luckily, modern CNC technology is allowing us to have all three without compromise. Laser and waterjet cutting services can provide quality parts, quickly, at low costs. However, there are a few differences between the processes that might affect your choice.
Production speed depends on a few factors:
- Type of material
- The thickness of that material
- Intricacy of design
Waterjet: Precision and Speed
Waterjet cutting can typically cut about 20” per minute in ¼” thickness steel. Though, accurate estimates of speed for this method will rely on the intricacy of your design quite a bit.
You see, if you have some steel you want to cut into a few simple shapes, like a square with a couple of holes in it, you’re probably going to see a fast production time. Suppose you wanted to create a sign with a beautiful, ornately detailed rose logo (and why wouldn’t you want that?). Your production time (and cost) will increase proportionately to the thickness of your steel.
It looks like we’ve found is an excellent segue into the next factor: precision.
Waterjet cutting is a relatively precise process, but you’ll need to prepare for a bit of tolerance. Tolerance is the positional change that occurs in a material when it’s cut.
For a quick visual, if you want one of your parts cut to a 10” length, and there’s a cutting tolerance of +/- .008”, your cut is within acceptable tolerance if it is between 10.008”- 9.992” long. Of course, we’re talking about eight-thousandths of an inch, but this can significantly affect your design if you are working with tab and slot assemblies, press-fit bearings, etc. If tight tolerances are critical to your design, you’ll want to consider laser cutting.
Kerf, within waterjet cutting, refers to the amount of material ejected during the cutting process. A common way to visualize it is to picture what happens when a saw cuts through wood. The blade removes some wood to make room for itself, and the kerf would be the thickness of the saw blade. With waterjet cutting, the kerf is the diameter of the stream of water plus the blended abrasive used to cut the material. Usually, the kerf is 0.020” to 0.040”, depending on the material processed.
Returning to our earlier example about the steel signage, if we wanted to have an extremely detailed rose logo, we’d have to consider our design’s small holes and features. Due to the waterjet’s large kerf, small patterns and tight inside radiuses can cause problems during the cutting process.
Overall, waterjet is excellent for big, simple shapes in materials over 1” thick. If you need nearly exact, detailed cuts, however, consider laser cutting.
Laser: Precision and Speed
Laser cutting is a swift manufacturing process. Modern fiber lasers can cut upwards of 500” per minute in some materials. Because lasers cut so quickly, they benefit from better machine utilization. Without going into too much detail, this means that your price will be much lower because your parts spend less time on the machines.
Cutting tolerance with a laser cutter is usually +/- 0.005”, or better. Contrary to waterjet cutting, laser cutting does not touch the material with anything besides light and uses only a tiny beam. The diameter for a standard laser cutting implement is around 0.006” (which, if you remember, is about the size of a human hair). If we applied this method to our rose logo example, we would experience virtually no issues with intricacy or detail, provided that we have appropriately designed geometry.
Thanks to the small beam diameter, the kerf is drastically reduced (and therefore, precision is increased) in comparison to waterjet.
When cutting metals with lasers, there is a phenomenon known as the HAZ, or heat-affected zone. HAZ can temper or anneal the metal’s cut edges, making it challenging to work within specific applications. HAZ was a big concern with early lasers in the 80s and 90s due to their low power and low processing speeds. With modern high-kW fiber lasers, the HAZ is negligible, if it exists at all.
In most cases, laser cutting is still the superior method in terms of speed and precision, enabling versatility and production timelines waterjet can’t compete with.
Cutting Service Costs
Here it is, the big one, the thing you likely care the most about: cost. I won’t bore you with lengthy explanations or entertaining anecdotes; let’s get right into the nitty-gritty. We compared our laser cutting prices with waterjet cutting prices from a leading waterjet service provider. The differences speak for themselves:
- QTY 1: $119.60
- QTY 2: $109.30
- QTY 10: $71.20
- QTY 1: $86.82
- QTY 2: $67.46
- QTY 10: $59.30
- QTY 1: $110.40
- QTY 2: $25.60
- QTY 10: $19.11
- QTY 1: $7.74
- QTY 2: $6.19
- QTY 10: $5.50
- QTY 1: $108.60
- QTY 2: $21.72
- QTY 10: $11.99
- QTY 1: $6.15
- QTY 2: $4.92
- QTY 10: $4.37
The key factors driving cost are:
- Time spent on the machine, the more intricate a design, the thicker the material, the more time it takes to make, increasing cost
- Material prices (this includes raw material prices), an expensive metal like copper or titanium will undoubtedly cost more than aluminum, and these prices often fluctuate
- Quantity of order, the more you order, the lower the unit price, thereby making it worth your while to consider fewer, larger orders as opposed to many, smaller orders
- Automation factors reduce the cost of fabrication by reducing the personnel involved in physical work
- Timeline, if you need your parts rushed, this can increase your cost, especially with a waterjet (waterjet prices for the above parts are double if you need them in under 10 days!). Of course, here at SendCutSend, we treat each order as a rush and do not charge additional fees.
Laser cutting is overwhelmingly superior in terms of precision, speed, and cost for many applications. As with most comparisons, however, it is crucial to consider the merits of both sides before deciding on a clear winner. Waterjet cutting has its place in the industry because it has low operating costs, it cuts thick material well, and it can cut a wide variety of materials, including stone.
That said, it’s worth getting a quote from a few laser cutting services (ahem…maybe us?) to see your options.
Get your instant free quote now! There are no strings attached here at SendCutSend. Really.