Quality Milling Tools: A Deep Dive into your Foundation of your Digital Workflow

In this webinar, Greg Everett from Sierra Dental Tool takes a deep dive into the foundation of your digital workflow. Explore the role of milling tools in the modern dental lab, how they affect your production, and most importantly – your bottom line. He explains how industrial tooling theory applies to the dental lab, how to identify common milling issues, and then breaks down the importance of using quality tooling in the lab. If you’re milling in your lab, this webinar is a must.

 

 

Now available on demand! Greg Everett, Vice President of Operations, Sierra Dental Tool explores the role of milling…

Posted by Zahn Dental on Wednesday, May 13, 2020

MillBox Experts – Round Table Discussion

In case you missed the live broadcast, check out the recording of the recent round table discussion we had with our friends over at CimSytstem!

“During this session, we cover some of the common support issues that come up in Dental CAD/CAM and some of the best ways to narrow down and solve them. We’ll also be discussing some key tools that are already available in MillBox that can help with common issues as well as upcoming updates that will make your MillBox CAM more flexible.”

WeTeamUp Terms: “Air Blast”

Air-Blast-Cover

[ er blast ]

 

What’s “Air Blast”?

An air blast is a device that delivers a stream of high-pressure air to the tip of the milling tool while it is cutting. They are widely employed in both industrial and dental grade CNC machines. The purpose of an air blast is to remove debris from the milling tool while it is cutting. It’s very important to move debris away from the tool because it prevents re-cutting of material. A properly set up air blast is essential for efficient milling all dry dental materials.

 

Interesting Details about “Air Blast”

  • Why is it important?

Milling inherently creates waste debris and it needs to be removed effectively. As a milling tool cuts and creates this waste, it is possible for the waste to stay in the cutting area. If this happens, the material will be re-cut. Re-cutting material creates extra heat, abrasion, and load on the tool. The use of an air blast assures that this effect is minimized.

  • Improper setup can cause problems:

Issues with air blasts are a leading cause of pre-mature chipping and/or tool failure. If your air is not aimed or pressurized correctly, it won’t work. Your milling machine will still operate, but the extra heat and abrasion is hard on the tool. Without air, the tool is essentially scrubbing its way through the material. This can reduce the life of your tooling and cause non-ideal milling results. If you’re getting margin chipping or your tools aren’t lasting, make sure to check that your air is at the correct pressure and properly aimed.

  • They affect milling temperature.

To a minor degree, air blasts also serve to regulate the temperature of the milling tool as it is working. The cool, dry air removes heat directly from the tool through contact, and indirectly removes heat by evacuating waste material effectively.

  • The source matters:

The compressed air you feed your milling machine needs to be very clean and dry. Untreated compressed air contains moisture, oils, and particulates. These contaminates can cause adverse effects if they contact your restorations and can also contribute to pre-mature spindle wear. If your air is wet, it can cause certain materials to cake on the milling tool – which also reduces tool life. The investment in good air filtration and drying is certainly well worth it.

 

Thanks for reading! We hope this break down of the term “Air Blast” has been of value. Stay tuned next week for another post like this!

 

 Check out the growing list of WeTeamUp Terms posts HERE

 

WeTeamUp Terms: “Yttria”

 

Yttria-Cover-image

What is “Yttria”?

[ih-tree-uh]

Yttria, otherwise known as Yttrium Oxide (Y2O3) is an additive used in all dental grade zirconia material. It is used to stabilize the zirconia during sintering.  As your zirconia restoration is sintered, it experiences a crystalline phase change. As the zirconia undergoes this phase change, it is inherently unstable. Without the addition of yttria, the zirconia we use would not have the properties needed for dental crowns.

Interesting Details about “Yttria”

 

  • Pure, unstabilized zirconia undergoes a phase transition from monoclinic (below 1170 °C) to tetragonal (between 1170 °C and 2370 °C) then to cubic (above 2370 °C). The use of a stabilization agent like yttria enables control of this crystalline growth. By changing the amount of yttria, we can control the strength and toughness of the final material.
  • The use of yttria in dental zirconia essentially “locks-in” the desired microstructure during sintering, thus allowing the correct crystalline phases in the material to develop. The stabilized zirconia has a much wider processing window, which allows multiple sintering temperatures and a reduction of the material’s sensitivity to variations in sintering process.
  • The concentration of yttria directly effects the strength and translucency characteristics of the zirconia material. Generally, the more yttria that is in the mix the more material will enter the cubic phase – resulting in more translucency and less flexural strength. This is why more translucent materials tend to be weaker.
  • “Zirconia” is a slang term. In the dental lab industry, when someone says “zirconia” it’s shoptalk for “Yttria Stabilized Zirconia”, or “YSZ”.

Thanks for reading! We hope this break down of the term “Yttria” has been of value. Stay tuned next week for another post like this!

 

 Check out the growing list of WeTeamUp Terms posts HERE

 

 

 

WeTeamUp Terms: “Collet”

Collet-and-tool

What’s a “Collet”?

[kol-it] – Noun

The collet is the mechanism that holds the milling tool in the spindle during operation. It transmits the spindle’s power into the tool while keeping it precisely centered under milling loads. In dental milling machines, the collet opens and closes to allow for tool a changes during milling.  A properly functioning collet is essential to trouble free dental milling.

Interesting Details about Collets:

  • Collets require regular care.

A dirty or worn collet doesn’t work correctly. Make sure you’re aware of the proper maintenance recommendations for your milling machine’s collet. It’s common for them to be neglected. Sometimes the pressure of production makes it easy to forget to care for your machine’s collet. Keeping your collet clean, inspected, and in overall good health will help you avoid common milling issues like chipping and premature tool wear.

  • Collets wear out.

The life expectancy on a collet will vary from machine to machine, but they all eventually wear. A worn collet will suffer from reduced clamping force and will fail to hold the tool perfectly centered. A poorly performing collet will increase the amount of tool runout you have. Typically worn collets will be accompanied by heavy tool wear and lots of margin chipping.

  • Sub-par tools can reduce collet life.

Tools and collets must be precisely matched dimensionally. Lower quality tools can be under or oversized. Any inaccuracy in the roundness of the tool will be translated to the collet and cause excess wear. Keep this in mind when you’re calculating the cost of your tooling options.

  • Check your collet first.

If you’re experiencing milling issues, it’s likely caused by a dirty or used up collet. It’s always less costly to replace a collet than your spindle. It’s good practice to rule out collet issues first when trouble shooting milling issues. In fact, we recommend keeping brand a new one in stock for this purpose. Having the part on hand can help get you out of a bind quickly.

Thanks for reading! We hope this break down of the term “collet” has been of value. Stay tuned next week for another post like this!