CNC vs Hydraulic Press Brake: Which Should You Buy?
Conventional hydraulic, NC/PLC and CNC press brakes compared, and how to decide which suits your shop.
"Should I buy CNC?" is the most common question we hear from press brake buyers. The honest answer depends on your parts, your batch sizes and your operators. This guide compares the three control levels: conventional hydraulic, NC/PLC and CNC.
The three types in one table
| Hydraulic (conventional) | NC / PLC | CNC | |
|---|---|---|---|
| Ram depth setting | Manual stops or limit switches | Programmed stop positions | Closed-loop control of each cylinder |
| Ram parallelism | Mechanical (torsion bar on many designs) | Mechanical (torsion bar on many designs) | Electro-hydraulic, using linear scales |
| Back gauge | Manual | Manual or motorised single axis | Servo, one or more axes |
| Angle calculation | Operator experience | Trial and stored setting | Controller calculates from material and tooling |
| Set-up for repeat jobs | Slow | Quick (stored jobs) | Quickest (stored programmes) |
| Operator skill needed | High | Medium | Lower for routine work, higher for programming |
| Investment | Lowest | Medium | Highest |
When a conventional hydraulic press brake is enough
If you do mostly one-off and short-run work with simple bends, and you have skilled operators, a hydraulic press brake is the most economical choice. It is simple to maintain and has few electronic parts to fail.
When NC / PLC makes sense
An NC or PLC press brake stores the stroke depth (and, with a motorised back gauge, the flange position) for each bend. For shops that repeat a regular set of parts with a few bends each, this removes most of the set-up time at a moderate extra cost.
When CNC pays back
A CNC press brake earns its higher price where:
- Parts have many bends that must relate accurately to each other.
- Batches are large or repeat often.
- Customers inspect to tight angle and dimension tolerances.
- You bend expensive material, such as stainless steel, where scrap is costly.
- You want to reduce dependence on a few highly skilled operators.
The savings come from shorter set-up, fewer rejects and faster bending of multi-bend parts. If those savings over a few years exceed the price difference, CNC is the better investment.
A quick test
Count how many times a week your operators set up the same part again, and how many parts are rejected or reworked for wrong angles. If either number is significant, programmable control will pay for itself. If both are near zero, a conventional hydraulic machine will serve you well.
What about electric press brakes?
Servo-electric press brakes drive the ram with motors and ball screws or belts instead of hydraulics. They are fast and efficient in small sizes but are generally limited to lower tonnages. Devraj Engineering builds hydraulic press brakes, which remain the standard choice across the 20-400 T range.
Frequently asked questions
What is the difference between NC and CNC press brakes?
NC/PLC machines programme stroke depth and back gauge but usually keep the ram level mechanically. CNC machines control each cylinder separately with linear scales and calculate the depth for a given angle.