In Programming and Design Phase (continue)


  • Try not to rotate the material (eg. a 180 degree rotation) to punch the other upper area. When the material is already punched half way, and is then rotated 180 degrees to punch the other section, the distortion due to the prior perforating process will make the repositioning of the original inaccurate. Although when punching a perforated sheet based on an image the accuracy factor is less critical, I still think that the sheet’s rotation during the perforating process is not desirable. I try to avoid as much as possible rotating the material when using a turret punch press machine. When rotating the material during punching, the “squareness”, flatness and dimension of material is extremely critical.
  • Try to make the repositioning process as small as possible. This is because the distortion tends to make the position after repositioning less accurate. Also, because of the distortion, there will be a risk that the clamper will not clamp the material properly. This will make the punching position less accurate.
  • Clamp reposition should be done before punching. If the perforated material is longer than the machine table and repositioning of the clamp is unavoidable, do the repositioning first before punching a hole. Then reposition the clamp in such a way that you can start the perforating process on the farther side first. Then reposition to the original location to punch the rest. By doing this, the position after clamping will stay as accurate as possible because the sheet still remains flat.
  • The perforating sequence can be done either row by row or column by column. Each style will give a bowing effect according to the direction of punching sequence. It is the programmer’s choice to decide the best sequence according to the nature of perforated panel’s material.
  • Try to punch the holes as far as possible away from the clamps to reduce the stress on both material and clamp. If the hole punch is too close to the clamp, it will give distortion and a bowing effect to the material.
  • Use cluster tools if possible. If your machine has the capability to use cluster tools and you have the proper tool and die to do so, use as many as possible. Fewer punching strokes mean less distortion on the perforated material and this will reduce the necessity to do a flattening process.
  • All in all, always refer to the special instructions in your machine’s operating manual and your turret punch software manual to get further information and to avoid any problems during manufacturing perforated sheet metal.

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