How to Measure Sheet Metal Parts
If you need to measure sheet metal parts, it’s crucial to know how to convert measurements from one unit to another. There are three common ways to measure sheet metal, including millimeters, mils, and gauges. Millimetres are the most basic unit and are often used in engineering and manufacturing. A millimeter is one thousandth of an inch. The gauges are more complicated but are used to measure thickness in relation to weight per square foot.
The most critical measurements are the 154.0 mm flange radius, the flange thickness, and the bend angle. While these measurements may seem small, they add up to a big difference in cost. To avoid this, you should let the bend radius float. If you can’t afford to let it float, you can lock the dimensions. However, make sure you don’t tighten up the dimensions too much or you will end up paying more than you should.
If you’re working with a supplier, document the way you inspect sheet metal parts. The customer’s requirements may require inspections in a restrained condition. Document your processes and be sure to communicate these to your customer. If a supplier is not clear about their procedures, they might not be able to comply with their contract.
Thickness is another important consideration when fabricating sheet metal parts. Depending on your project, these can range from 0.9mm to 20mm. You should also pay attention to the outside radius of a curl or hole. Also, make sure to account for hems (folds at the end of a part to give it a rounded edge).
A CMM’s accuracy is adversely affected by the edge profile of the sheet metal part. As a result, it is typically less accurate than a simple caliper when measuring features that are defined by edges. As an example, imagine a sheet metal part with a 5% edge profile. In this case, the hole diameter on the top surface is 1mm larger than the one on the bottom. The thickness is 10mm.
To measure a 3-degree open bend, you need a surface plate, an angle block, and a height gauge. Holding the part wrongly will tilt it up, causing the height gauge to measure inside the edge of the material. To measure perpendicularly, you should hold the part perpendicularly to the angle block so that the edge of the height gauge remains flat against the edge of the material.
You can also use a thimble to measure the thickness of sheet metal parts. This will help you find out how thick or thin the part is. You should take note of the distance between the tabs and the bend so that they don’t distort the sheet metal. If you don’t follow these rules, the part might become inaccurate. However, the accuracy of these measurements is critical for your parts. There is a right way to measure sheet metal parts.
When measuring for holes and slots, make sure the holes are at least 0.062 in. away from the edge of the material. Also, make sure the holes and slots are at least six times wider than the material thickness. If you need to place holes or slots close to a bend, you can use a hole-cutting machine. But make sure to check the manufacturer’s specifications for the dimensions of the holes and slots.
