A corner radius is the curved part of an edge that links the straight edges together. These corners may be long and gradual or short and tight. It may not be possible to bend some rubber profiles around very tight corners. This help guide provides two methods to determine the size of your radius so that you can decide whether our seals will be suitable.
Option 1: Using a Ruler to Measure a Corner Radius
One way to measure the corner radius is to draw two lines where the curve starts to straighten (as shown in the diagram). You can then measure the distance from the point where the two lines intersect to any part of the radius (ie, the curve of the corner).
For example, if this distance measures 75mm, the radius of the corner is 75mm.
Option 2: Using an Item to Measure a Corner Radius
Another way of measuring the radius of the corner is to place a circular item (such as a plate, glass, tape reel etc) in the corner. It is important that you choose the correct size item to ensure you obtain an accurate measurement of your corner radius. The item needs to fit perfectly into the corner so that the curve of the item matches the curve of the corner. This may involve trying several circular items until you find one which is a good size.
Once you have found an item that fits your corner, measure the diameter of the item as shown in the diagram. After you have taken this measurement, you can obtain the corner radius by dividing your measurement by 2.
For example, if your plate, glass or other item measures 150mm diameter, your corner radius will be 75mm (half of 150mm).
Bend Radius Diagram Definitions
Bend radius diagrams for a number of our clip on edge trims, window seals and rubber extrusions can be found in the bottom right hand corner of the product drawing on each product page. Depending on the type of profile, seals often bend differently in different ways. These figures indicate the minimum radius that the seal can be bent for each origination whilst still allowing it to fit correctly without affecting the sealing face.
Whilst these diagrams provide the minimum recommended bend radius, it is sometimes possible to adapt the seal so that it can be used around tighter corners. One option is the cut and mitre the profile by cutting small triangles out of the inside to reduce buckling as it is bent. With clip on edge trims it is also possible to insert a small piece of expanded neoprene cord inside the sponge sealing bulb. This will help reduce the bulb from compressing.