Laser Cutting
Resource Material
Considerations when laser cutting metal
General Cutting Tolerances
For mechanical reasons, there are slight dimensional deviations in the manufacture of metal parts. So that the end result still meets your requirements, these deviations are defined as tolerances. The tolerances that can be achieved differ according to the various processing methods.
Typically, cutting accuracy varies from approximately 0.1mm at 0.5mm thickness up to 1.1mm at 25mm thickness.
Surface quality:
- Laser parts with visible side and PVC coating: No surface defects are permitted on the visible side.
- Laser parts with the visible side without PVC coating: Small marks are permissible.
- Powder coating: No surface defects allowed. Exception: small flaws in the holes or recesses that are used to hang up the parts for the coating are permissible.
- Deburring: Small marks are permissible. No gouges or scratches.
- No special surface treatment: Scattered areas of scratches, flash rust and spatter allowed.
Cut quality:
A score-free cut can be expected with steel, up to 10mm / stainless steel, up to 6 mm/aluminium 4mm thick.
With thicker materials, this can no longer be guaranteed.
Minimum dimensions for laser cutting
Even though laser cutting is very accurate, there are limits at which the desired quality can no longer be achieved if the energy input is too high on a small area. Therefore, the minimum dimensions should be observed when constructing metal parts:
- Minimum component dimensions: 25 x 25 mm
- Maximum component dimensions: 2990 x 1490 mm * may vary by material type
- Minimum hole diameter = 0.7 x material thickness
- Minimum web and slot width = 0.7 x material thickness (e.g. for ventilation openings)
- Minimum component size up to 8 mm material thickness = 15 x 15 mm, from 8 mm material thickness = 25 x 25 mm
Please note: Even if the minimum dimensions are observed, the heat input can lead to distortion of the components. This can also be increased by stresses in the sheet metal.
Minimum dimensions for laser cutting
The maximum component size for laser cutting depends on the sheet size used. Please note that if the next larger sheet metal format has to be used, the production costs will increase accordingly. So sometimes it’s worth cutting a few millimeters off to minimize costs.
Due to the supplier sheets not always being perfectly square, it is best practice to keep the component size at least 5mm inside sheet extents, for this reason, use maximum component dimensions per example sheet sizes below :
- Component max 2390 x 1190 -Sheet 2400 x 1200
- Component max 2428 x 1209 -Sheet 2438 x 1219
- Component max 2490 x 1490 -Sheet 2500 x 1500
- Component max 2990 x 1490 -Sheet 3000 x 1500
**if the part length exceeds sheet size, the part will require splitting or be omitted.
Holes intended for tapping
Thread | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 |
|---|---|---|---|---|---|---|---|---|---|
Hole size | 2.5 | 3.3 | 4.2 | 5.0 | 6.8 | 8.5 | 10.2 | 12.6 | 14.0 |
Countersinking
Your 3D models should include the main hole but not the chamfers, an etched line for chamfers can be included.
Tabs/bridges when cutting letters
If you want to have lettering cut out, you have to consider that the inner parts of the letters also fall out of the sheet during laser cutting. In order to get these inner parts you need to connect them to the rest of the sheet metal
