Do You Really Need a CNC?

In our modern world automation is often seen as the pinnacle of manufacturing. But is the CNC actually an automated system or is it a time drain?

I’ve seen three different approaches to the CNC. I have worked at a shop with 5 different CNC’s running simultaneously including an autoloader, two 3-axis CNC’s, and 2 5-axis CNC’s. I’ve worked in a shop that had one 3-axis CNC, and I worked in a shop that didn’t have a CNC at all. All 3 of these companies were profitable.

I have found that unless you’re doing large batches of the same cabinet configuration or custom designs, CNC’s don’t save you time or money in manufacturing. Let’s break it down a little bit. While from the outside, the CNC seems like a set it and forget it piece of machinery it’s really not. The CNC requires you to program the tool paths. While yes there are programs that enable automatic programming, such as cabinet vision, these programs are often slow and give up efficiency in engineering and design while also increasing overhead for small cabinet shops. I can design, change dimensions quickly, engineer and print blueprints for the shop on AutoCAD in a fraction of the time it takes for someone to create one iteration on Cabinet Vision.

In addition programs like Cabinet Vision must be paired with programs like AutoCAD for custom drawings to be printed and sent to the shop. Finally, the CNC then needs to be monitored for the duration of the program, and these machines while accurate typically use router bits, so the process of cutting is often slower than other methods. In the shops that didn’t rely upon their CNC machine to cut out cabinet boxes, they used a 3 phase sliding panel saw, a hinge boring machine, and a line boring machine for shelf pins.

In these shops, the engineer, who is generally paid more than the guys in the shop, isn’t bogged down by assembling every cabinet in a cumbersome program before sending the prints off to the shop. The blue prints were sent to the shop with the pertinent information to create cut lists and assemble the cabinets. Most competent carpenters can read a blueprint and generate a cut list. This isn’t a task that is required to be done by an engineer. In addition, thanks to advances in technology, there are free nesting programs online that the shop can use for ensuring efficiency when cutting panels on a sliding panel saw. As well, the line boring machine works significantly faster than most CNCs on the market for inputting shelf pins. As well, a properly set up and jigged hinge boring machine also works faster than most CNCs on the market.

In this method, cabinet shops save time in the process, since the manual process is faster than a CNC. Some people may disagree and believe having some of their highest paid employees programming every hole and cut, while having a lower paid employee standing next to a CNC monitoring it all day is wise. I will say I agree with them on the wisdom of it at a certain scale. A scale where the shop exceeds a certain level of man power, while also having a higher turn over rate. In these instances, it is wise to have longer term employees programming each cabinet on a CNC machine. However, when we’re discussing bespoke millwork shops with fewer than 25 employees it’s not so clear that a CNC handling all of the cabinet load is the wisest solution, and instead dispersing the engineering responsibility in a decentralized manner gives a competitive edge in cost reduction.

Looking at tools it’s clear where the cost savings are.

An autoloading CNC starts at $100,000 and goes up from there. In addition to the cost of purchasing the machine there are several annual costs that need to be considered. These include maintenance, tooling, repair, and software, which adds between $10,000 to $20,000 per year in overhead.

Meanwhile, a sliding panel saw, hinge boring machine, and a line boring machine can all be purchased for less than $30,000 combined. As well, the yearly maintenance cost of all of these is much lower CNC. These machines also don’t require a separate software to function effectively, saving thousands on yearly overhead.

CNC’s are great and can do some really cool things like creating designs, curves, and a variety of other custom patterns, including boring doors for hinges and handles, and milling out panels for door straighteners, creating custom panel profiles, etc. That’s really where they shine the most in smaller bespoke cabinet shops. They also tend to do very well in large scale operations that produce the same cabinet design multiple times. However in a bespoke shop where every kitchen, bathroom, and closet has a different layout with varying cabinet sizes, they just don’t save time or money, and instead cost more time and money to produce these kitchens.

So when considering a CNC as a small shop, consider what your work load is and what you want to use it for. Ask these questions.

• Do I want to mass produce cabinets?

• Do I want to increase my custom capabilities in carving, custom designs, curves, etc.

• Is my company large enough to afford the overhead costs that accompany the CNC, and will the additional work I can take on offset those costs in a meaningful way?

• What else could I spend $100,000+ on that may have a better impact on my efficiency and capacity?

I’m not saying don’t get a CNC, just make sure it’s actually a wise move and makes your company better, not worse.