Planning Laser Cut Parts That Need Forming
The laser cuts a flat blank. Everything the press brake has to achieve belongs in the request before that blank is cut, not after the first part is bent.
A laser cuts flat. A press brake does not. Any part that is cut and then formed is really two parts on one drawing, and the gap between them is where most first articles go wrong.
The blank is not the part
A flat outline with bend lines marked is the blank. The delivered component is the same material with angles in it, and some dimensions only exist after forming. If the drawing shows the finished shape and the cut file shows the blank, both have to be present, and they have to agree.
What KorFab needs to know is which flat pattern produces the finished geometry. Where the flat is developed by your design team, the relationship between the two is already decided. Where the request only shows formed dimensions, that becomes part of the review before anything is cut, and it is worth saying so up front rather than after the blank is on the bed.
Three things to communicate before cutting
- The finished form: angle, direction of each bend and the inside radius, or a note that the shop may choose it.
- Which face is the reference. A bracket formed from one side is not the same part as the same bracket formed from the other, and the difference usually shows at assembly.
- Features that must stay true after forming: holes, slots and cutouts whose position matters once the material has moved.
Bend lines can be marked, not measured
The laser marks bend lines in the same program as the cut, and the press brake runs a program for each bend with the backgauge set by the control. That means a bend line in the cut program and a dimension on the drawing are two ways of saying the same thing, and having both agree is what keeps the angles repeatable across a run.
What the brake adds to the question
Bend length, the distance between the frames and the throat depth decide what a part can be, independent of tonnage. A formed part that has to pass between the frames is limited by width in a way no force chart shows. The force a bend needs depends on material, thickness, bend length, die opening and method, which is why forming capacity is confirmed per part.
The sequence to plan for
Cut, form, weld, finish is the usual order, and every step can move a dimension. A hole that has to be tapped is easier before forming, while the part is still flat and easy to hold. Planning a component that needs more than one operation walks through that sequence, and a flat drawing or a formed drawing covers which drawing to send.