Cutting Wheel in Singapore application

Terms and Terminologies – Cutting wheels and Grinding discs

In the world of bonded abrasives, there are no industry standards when it comes to how products are named. This happens even at a very high level of product naming – take for example grinding discs and cutting wheels. These are not the only names given to these classifications of products.

Commonly used names by other manufacturers and users include:

  • Cut-off wheels
  • Cutting discs
  • Cutting-off wheels
  • Grinding wheels

In general, the most common term is cut-off wheels and grinding discs. In our product range, we choose to use the term cutting wheel instead to simplify the “cut-off wheel” name, which is in our opinion clunky. However, regardless of the names and terms given by all the different manufacturers, there are very practical standards when it comes to real-world use of the disc, such as standard sizes, thickness, materials, and applications.

Ultimately, what matters is not what a product is called; quality should always be judged by performance. This article is to clear up any confusion or misunderstanding of any of these terms.

Grinding Disc in Singapore Application for finishing

Bonded and Coated Abrasives

In our website and literature, we often state that Vogel is a brand of bonded abrasives. What exactly are bonded abrasives, and how are they different from normal abrasives?

Abrasives is a very broad category of products which has a main function – to shape and finish a workpiece through rubbing and wearing away the material. Today, the terms mostly means industrial abrasives such as sandpaper, as well as cutting and grinding discs.

These industrial abrasives can then be further subdivided into two separate categories – coated abrasives, and bonded abrasives.

Coated abrasives are products which has abrasive material or abrasive grain coated on the top layer of a backing. Sandpaper is a coated abrasive, as sandpaper is made of a backing (paper or cloth), with abrasive grain such as aluminium oxide or silicon carbide coated on the top layer by using resins. Application of coated abrasives are always on the coated side, of course.

Coated abrasives include sandpaper in the form of rolls and belts, and also include flap wheels and flap discs, as these are in essence made of sandpaper.

Bonded abrasives, on the other hand, do not have a backing. Bonded abrasives are abrasive material or abrasive grain being bonded together using a bonded agent. This is how grinding discs and cutting wheels are made – abrasive grain such as aluminium oxide is held together by a bonding agent and further reinforced by fibreglass netting. There is no backing and no coating – hence the term bonded abrasives.

Bonded abrasives primarily consists of cutting wheels and grinding discs in different shapes, sizes, and dimenions.

With Vogel, we only supply bonded abrasives. PFE Technologies carries a separate range of coated abrasives and you can find out more information at our PFE Technologies website.

PFE Large cutting wheel

Cost vs Performance of Cutting Wheels

In the industry of bonded abrasives such as cutting wheels and grinding discs, products are usually measured, and decisions are usually made only based on prices and cost. In this article we hope to bring to light some easy methods to calculate how much your products actually cost based on their performance, and this is far easier to measure with cutting wheels than grinding discs. As such, this article shall focus only on cutting wheels.

As a purchaser of high-volume consumables such as cutting wheels or grinding discs, it may be the easiest approach to only factor in price in your purchasing decisions. A 10 cent reduction in price by switching brands is naturally an attractive deal as it brings to the table direct 10% savings, at least on paper.

This is a problematic view because it does not take into account the efficacy and performance of the products. Not all cutting wheels are the same. A cheaper product may very well only last 80% of a higher quality, more expensive product. In such a scenario, would a 10% cost reduction save your business money, or actually cost you more? It’s not that hard to find out.

To find the true cost of your consumables, first we must establish the function of a cutting wheel – it is, in essence, a tool used to cut materials. Therefore a cutting wheel’s worth can first and foremost be measured by how well it cuts. Quantitatively, we can easily measure how many times a single piece of cutting wheel can cut a standard sized material. This is a test we encourage all businesses to do, to ensure the value they are getting from their cutting wheels. Consider this scenario:

Test method:

Using two similarly sized cutting wheels, keep cutting a standard test object to obtain the results of how many pieces one wheel can cut.

Standard test object should be made of a material commonly used in your production but thin enough to show clear qualitative differences, such as a a 2 cm thick, 2 cm deep stainless steel bar. The material dimensions should be kept constant as much as possible.

Taking the price of each wheel into account, calculate the price per cut.

As an example:

1. Brand A Cutting Wheel, 100x2x16mm – $0.65 – 12 cuts – $0.054167 per cut

2. Brand B Cutting Wheel, 100x2x16mm – $0.75 – 18 cuts – $0.041667 per cut

Here you can see that while Brand B has a higher price of more than 10%, its higher performance more than justifies the price of the wheel as it ultimately achieves a lower cutting cost. In fact, based on this evidence, we can already tell that once you factor in the performance, Brand B is actually cheaper by more than 15%.

To take things further, we can establish not just the price per cut, but time efficiency per cut. This is when we measure how much time Brand A and Brand B requires to cut a single piece. If Brand A cuts the standard test object in 28 seconds, while brand B takes 24 seconds, we can further establish that Brand B is more efficient in terms of time. Why is time important? Because you have to pay your workers. If your workers can achieve more cuts per unit of time, you are essentially further reducing the cost per cut!

With the scenario as above, we can make this perfect scenario:

Cost of labour for one worker per hour – $30

Brand A Cutting Wheel – $0.65 – Cuts in 28 seconds – 128 cuts per hour – Labour cost per cut = $0.234

Brand B Cutting Wheel – $0.75 – Cuts in 24 seconds – 150 cuts per hour – Labour cost per cut = $0.200

With a faster cutting wheel, your labour costs will be decreased per cut.

Of course, this is a perfect situation where a worker keeps cutting without stopping, and without slowing down, and the cutting-off wheels are magically reappearing back on the machines without the worker needing to change them. We cannot include every single factor in our experiment, but just using these two examples already illustrates how much savings a business can make just by ensuring a good price-performance ratio in the products it chooses. When extrapolated to real-world figures (most business use hundreds of cutting wheels a month), using a more expensive, but more efficient cutting-wheel may ultimately save the company thousands of dollars per year!

Many other factors must also be taken into consideration, but are much harder to quantify in an easy way.

  1. Safety (by far the most important factor – who knows how much costs, mental or financial, will be incurred for a single injury)
  2. Consistency of quality (if subsequent batches perform poorly, your calculations are no longer valid)
  3. Stock availability
  4. Lead times
  5. Delivery times
  6. Delivery costs

Ultimately, the choice of cutting wheels is not a simple one to make. It is easy to go the simple way and choose by price, but there are many good reasons and benefits to the company to consider a quantitative approach towards consumable decision making.

For us at PFE Technologies, we distribute and supply our own Vogel brand for good reason – we have to ensure great quality at a good price, which is always recognizable by our brand. We strive to make purchasing decisions easy for customers by providing consistent great value. If you haven’t tried out products, we strongly encourage you to do a test with our products, whether big brand names like Norton, Makita, or Bosch, or even smaller unheard of brand names. We strive to provide value that appeals to the entire spectrum of quality, so give it a try. You might be surprised at what a local Singapore company can do.