Warping and bowing in Laser Cut Materials

What is Warping?

Warping is the unwanted bending or mis-shaping of your parts. Whether you intend your parts to be flat, square, curved, round, etc., if it bends or twists unintentionally, that’s warping. Unintentional/undesirable warping can inconsistently happen to all parts.

What Causes Laser Cut Parts to Warp?

Steel isn’t naturally flat. When it’s rolled, cooled, and coiled at the mill, it wants to stay in its original shape and molecular composition. There are multiple reasons a laser cut part could warp, but fundamentally it happens because internal stresses inside the part become unbalanced. Most materials hold whatever shape they’re in (whether that’s flat or bent) because of the way they’re stressed.

Imbalance can be caused by increasing or decreasing stresses in the part unevenly. Or it can be caused by removing partial sections of stressed material.

Preventing Warping in laser cut components

When it comes to laser cutting flat panels, the more material being removed over a certain area, the more likely warping is to occur. Grill-like mesh shapes or long, thin shapes are most likely to warp as the material is removed. Removing more than about 50% of the area starts to increase the odds that the part will warp. If you can remove less area, that will help, but sometimes your design needs to remove more material to reduce the severity.

We review each design before it’s cut, to check for things like how likely it is to warp from our experience. If we think your part has a high risk of warping, we may reach out to you before laser cutting to explain how it might impact your part or see if the design can be altered to help reduce the stress on the material. Sometimes the exact same part can be cut multiple times and not warp the first time, but warp significantly the second time.

What if My Laser Cut Parts Warp?

Having a part that’s warped doesn’t always mean the part is unusable, although it may be undesirable. Depending on the application of the part, it may still be functional. Sometimes a warped part can be simply bent back into the desired shape. Parts that get assembled may naturally bend back into the correct shape as they are adjoined to other pieces.

The mesh part pictured is 360mm x 150mm in 1.5mm 3042b, it is an example of what can happen to a perfectly flat piece of steel, this is considered as extreme bowing. Bowing to this piece could be reduced by decreasing the number of holes within the design.

We’ll do our best to let you know if parts in your order are likely to warp during the quotation stage and will highlight this risk within our email communication to you.

If you choose to proceed with the risk and your parts do end up warping or bowing during laser cutting, we may reach out to you to discuss what can be done, however, the parts may not be rejectable, and recuts may have the same outcome.