As Old Man Winter rolls across Lake Erie settling into Northwest Ohio; (home of Crown Foam Technologies) many of us that endure the winter winds, snow, and cold, dream of summer days -reminiscing about the call of our Great Lake to watch the boats on the horizon while lounging on her sandy shores soaking up the warmth of the sun…
If only that were the real reason that I am chatting with you today.
Let’s discuss a different type of Shore. A shore that will help you in selecting the correct foam product for your project. But first, A history lesson.
In the 1920’s, an American Metallurgist name Albert Ferdinand Shore invented the Shore Scale. The scale is used to measure the “hardness” of different materials. In total there are 12 different scales.
A, B, C, D, DO, E, M, O, OO, OOO, OOO-S each scale ranges in value from 0-100. The higher the testing number the harder the material. Crown Foam Technologies uses Shore 00 as our rate of measure. Shore 00 is used to test the “hardness” of soft polymeric cellular foams/polymers. Due to the vast amounts of polymeric products throughout the industry, it stands to reason that there will be instances when scales will overlap. In our case. Scales A, B, C, D, O, and OO have some overlapping values (to simplify our chart, we are only concentrating on OO, A, and D). To help you cross-reference these scales and values, we have created an easy to use chart that gives a relatable image to the Shore number.
For Example, extra-soft foam would relate to a gumdrop or a gel laundry pod, Medium Soft would be relatable to an eraser, while Extra Hard correlates to a football helmet.
Please keep in mind that this is only a guide and the values are approximate.
Knowing the shore is very important to foam success or failure in the field. Take a moment and consider some of the items that are produced with foam. Shoe Insoles, ink pads, weather stripping, medical devices, mousepads, earplugs. The list could go on and on. Each of these applications has a specific level of “hardness” or shore that makes them useful. Imagine using weather stripping that is hard as a football helmet. It would never conform to the shape of the window or door and would be considered useless. Now you know the purpose and importance of Shore. Where do all these numbers come from? There must be some universal guide to the scales. How is the shore number determined?
Shore is measured by a device called a Durometer. Dur, meaning Hard or tough in Latin and OMETER which is generally referenced as a measuring device. The Shore durometer was not the first device developed to measure hardness. However, it was patented in 1930 by Albert Ferdinand Shore and is the general standard that is used today. This specialized device uses consistent force to push a presser foot into the product which provides the amount of resistance the product gives to indentation. The resulting number indicates the shore number of the item being tested. Now that you are ready to talk shore, click on this link to upload your CFT Shore chart.
Also, be sure to check out our blog spot on www.crownfoams.com.