Technical knowledge library
Find technical guidance, selection references and related machines by production question.
How to Calculate Press Brake Tonnage
Nearly every article about press brakes uses the same formula:
Choosing the V-Die: One Wrong Step, One Ton Off
People often fill in the tonnage calculator, look at the number and think it "looks off". Usually it isn't the formula — it's the wrong V-die.
Flat Length: Why Your Blanks Come Out Short
You finish a bend, measure it, and it's a few millimetres shorter than the drawing. This is the single most common mistake in a shop new to sheet metal.
Minimum Flange Height
Some parts look simple but cannot be bent: the flange is too short, and the blank slides out of the die the moment the punch comes down.
Laser Cutting Gas: Nitrogen, Oxygen or Air
Choosing the wrong assist gas changes cutting speed by up to ten times on the same machine.
Stainless on a 12 kW Machine: Air Nearly Matches Nitrogen
Here is a set of numbers few suppliers volunteer.
Is More Laser Power Worth the Money
A question that comes up in every machine selection: "If I go 6 kW instead of 3 kW, it's twice as fast, right?"
What Steel Is CT3? An Honest Answer
You are used to specifying A36 or S235. You buy plate in Vietnam and the quotation says "CT3". The natural next thought is: that's the same thing, isn't it?
Tube Bending: When You Must Use a Mandrel
Tubes that flatten, wrinkle on the outer radius, or come out oval — most of these cases come down to two ratios.
Laser Source Overheating: Four Numbers to Remember
The machine reports a temperature fault and locks itself out. This is one of the longest-downtime failures a shop faces, and most of it traces back to the cooling system.
Press brake controllers: TP10S, ET15 or DA53T?
Press brake controllers: TP10S, ET15 or DA53T?
3000W or 6000W fiber laser: choose by the work, not the number
3000W or 6000W fiber laser: choose by the work, not the number
1500W or 2000W laser welder: power is not everything
1500W or 2000W laser welder: power is not everything
Tube bender: NC or CNC, and what do 2A1S and 3A1S mean?
Tube bender: NC or CNC, and what do 2A1S and 3A1S mean?
How much does a CNC press brake cost? Ranges by tonnage and length
How much does a CNC press brake cost? Ranges by tonnage and length
Fibre laser cutter prices: ranges by power and bed size
Fibre laser cutter prices: ranges by power and bed size
How much does a tube bender cost? NC and multi-axis CNC ranges
How much does a tube bender cost? NC and multi-axis CNC ranges
Laser welder prices: why the same machine has two prices
Laser welder prices: why the same machine has two prices
Tube flattening when bending: causes, and when a mandrel is mandatory
Short answer: A tube flattens because the wall has nothing supporting it from inside while it is drawn around the die. Two ratios decide how badly: bend radius over outside diameter (R/D), and outside diameter over wall thickness (D/t). The smaller the R/D and the larger the D/t, the more it flattens. Past a certain point, nothing fixes it except a mandrel.
Inner-wall wrinkling when bending tube: causes and the wiper die
Short answer: The inside of the bend is being compressed. If the material has nowhere to go and nothing supporting it, it folds into wrinkles. A wiper die fills the gap between the bend die and the tube right at the tangent point — that is the component designed to cure this. But before blaming the wiper, measure the tooling clearance.
Tube scoring when bending: tooling, lubrication and speed
Short answer: A tube scores because there is friction where there should not be. Three common sources: the mandrel rubbing the inner wall, the clamp die gripping too hard, and worn or material-loaded tooling surfaces. On decorative stainless this is not a minor defect — scoring is what gets parts rejected.
Laser welds with porosity, burn-through or lack of fusion: cause table
Short answer: These three defects have three different root causes. Porosity usually comes from shielding gas or surface contamination. Burn-through means too much energy for that thickness. Lack of fusion is the opposite — or the joint gap is so wide that the energy passes straight through it. Before adjusting the machine, look at the joint.
Laser welding gun not firing or weak output: a safe order of checks
Short answer: Before opening anything, switch off the laser source and follow a safe order. Most "no beam" cases sit in the safety interlocks, the chiller or the protective lens — not in the laser source. Do not start by dismantling the source.
Inconsistent bend angles: 4 causes and the order to check them
Short answer: Inconsistent bend angles are almost always one of four things: non-uniform sheet, worn or misaligned tooling, bed deflection under load, or inconsistent part placement. The order you check them in matters more than the list itself — check in the wrong order and you will adjust the machine to compensate for a material error.
Springback in bending: why the angle is always a few degrees short
Short answer: Springback is not a machine fault — it is a property of metal. When the tooling releases, the elastic portion of the deformation recovers and the angle opens up. Your job is not to eliminate it but to overbend by a consistent amount. The real problem only appears when the springback amount is inconsistent from part to part.
Marks on the sheet after bending: causes and how to avoid them
Short answer: Marking comes from the V-die shoulders dragging on the sheet as the material is pulled into the opening. Three things set the severity: shoulder radius, V width relative to thickness, and the condition of the tooling surface. On thin stainless and pre-painted sheet, marking — not angle — is usually what causes rework.
Press brake crowning: when you need it and how much
Short answer: During bending, the force pushes the ram down and the bed up. Both deflect in the middle. The result: the angle at mid-sheet is more open than at the ends. Crowning lifts the middle of the bed to cancel that deflection. The question is not whether you need it, but how much, at what load.
Not cutting through, burrs, edge burn: a cause reference table
Short answer: These three defects almost always come from the same group of variables: focus, assist gas, nozzle, speed and optics condition. What matters is checking them in order — change two things at once and you will never know which one fixed it.
Protective lens dirty or damaged: how to tell, and how to change it
Short answer: The protective lens is the cheapest piece of glass in the cutting head and the first to fail. It exists to be sacrificed in place of the far more expensive focusing lens. Dirty can be cleaned; burn-pitted must be replaced — and cleaning a burned lens will damage what sits behind it.
Laser cutting nozzles: when to change, what size, single or double
Short answer: The nozzle shapes the assist gas jet. Three decisions: orifice diameter (by thickness and gas type), single or double (by oxygen vs. nitrogen), and when to change it (when the orifice is no longer round). A deformed nozzle ruins the cut edge faster than any parameter error.
Laser cutting gas consumption too high: 6 places to check
Short answer: Assist gas is usually the largest operating cost of a fibre laser cutter — larger than electricity. And most of the wasted gas is not burned while cutting; it is burned while not cutting. Six places to check, in order, none of which cost anything.
NC or CNC press brake: what actually differs, and when you need CNC
Short answer: The real difference is not the letters "CNC." It is how many axes the machine controls itself and whether it has automatic crowning. Torsion-bar machines are typically 2-axis, repeatability around ±0.1 mm, no crowning. Electro-hydraulic servo machines are typically 4+1 axis, repeatability around ±0.05 mm, with motorised crowning. If you run a few fixed part types, you will not use that difference. If you change parts several times a day, it decides how long each changeover costs you.
Press brake maintenance: daily, weekly, monthly — and what actually fails
Short answer: Most expensive press brake failures do not come from accidents. They come from three things left alone too long: dirty hydraulic oil, tooling that is never cleaned, and a back gauge running in dust. The schedule below is short, and most items take under 5 minutes.