Is a 50 Durometer Roll the Same from Every Vendor?

Imperial Rubber Products Technical Director Steve Huff uses two bouncing balls to help you see that all rubber coverings by the same name are not the same.

Transcription - Is a 50 Durometer Roll the Same from Every Vendor?

Today we’re going to talk about rubber compounds.

You know, a lot of people think they can go to any manufacturer that sells rubber covered rolls and they think it doesn’t matter. They’re just going to shop on price.

Well, I’m here to tell you that it makes a big difference, because one rubber cover is not the same as another rubber cover, even though Vendor A says they have 50 durometer neoprene, and Vendor B has a 50 durometer neoprene, it doesn’t mean they’re the same.

In fact they’re probably not anywhere close to being the same.

So today we have two balls here. They’re made out of the same base polymer. They are made at 50 durometer each.

But they’re compounded differently, or mixed differently.

So let’s take a look to see what we’ve got going here.

[Ball bounces] Vendor A. [Ball lands with a thud] Vendor B.

Are they the same? You tell me.

Imperial Rubber - How to Take a Durometer Reading

Imperial Rubber Product's Technical Director Steve Huff explains the proper way to take a durometer reading on a rubber roller.

Transcription - How to Take a Durometer Reading

Now we're ready to take a durometer reading. Remember, always take the dial, the little red dial, and put it back to zero before you start.

The proper way to take a reading is to align the base parallel to the axis of the roll. At that point you roll it forward, and back, and then you have a reading. In this case, it's 28.

The wrong way to do it is to put it perpendicular to the axis. If you take it and you roll it this way, that's wrong. That will give you a wrong answer. See in this case, it came out to 31. Completely wrong and bogus number.

Again, the right way, parallel to the axis, forward and back, 28.

Imperial Rubber - How to Calibrate a Durometer

Imperial Rubber Product's Technical Director Steve Huff explains that before taking a durometer reading, it is critical to calibrate your durometer.

Transcription - How to Calibrate a Durometer

Before taking any durometer readings it is imperative to make sure that your durometer gauge is properly calibrated.

All good calibrated durometer gauges come with a standard to compare it against.

So we need to double check the standard first. So in this case, the standard says, A for Shore A, 72 ±1. So we'll take the gauge, put it on here, take the reading. And this reads 73, 72 ± 1.

We know we're ready to take the measurement.