Signs Your Deep Drawn Supplier Doesn’t Know What They’re Doing

Like any other product or service, there are always choices when selecting a deep drawn supplier. And like any other project, you want to find the one who will provide the parts that you need, at the best cost available. Problem is, as the customer, deep drawn stamping is not your specialty. So you contact a few suppliers for quotes and maybe a few prototype parts, and now you are sitting at your desk with samples of deep drawn parts, trying to decide which is best.

You turn them around, look at them from different angles, and hold them under light for a better view. After a short while, you realize that you have no idea what a ‘good’ part would look like next to a ‘bad’ one.

The deep drawn stamping process is more complicated than it seems.There are many visual and tactile indicators hidden in the final products that can provide plenty of information to let you know whether the supplier has the skills and experience to produce the level of quality that you need.

Hairline Fractures in the Material

If the process die is not set correctly, the forces of drawing the material can create small fractures in the metal. Look closely at the surface of the part for any cracks or lines. The surface should be smooth and intact.

Wrinkles on the Top Edge

The act of drawing metals with a punch and die is a careful balancing act between the pressure holding the blank in place and the force of the die. If that balance is wrong, small wrinkles will appear on the top edge or flange of the final part.

Uneven Top Rim

While you are inspecting the upper edge, turn the part slowly and look for uneven thickness or out-of-round in the rim. If the press was set up correctly, the rim should be concentric.

Fractures at the Bottom of the Cup

Turn the part over and look closely at the bottom of the cup. This is the extent of the drawn material, where the punch stopped. This surface should be smooth and even. If there are fractures in the material, it can indicate incorrect die design or poor machine maintenance.

With these few indicators in mind, that pile of parts on your desk should have a very new tale to tell.