Proper cooling at the cutting edge, reducing tool projections as much as possible, and using a very strong, rigid fixture setup on the machine will help deal with the challenges of milling cobalt chrome. With the high price of the material, ensuring process reliability through proper tool selection and cutting parameters is essential.

Foschaar added that solid-carbide tools are preferred for machining cobalt chrome materials. Carbide cutting tools generally have thermal shock-resistant properties while at the same time have a high degree of bending strength and fracture toughness, making them suited for the characteristics of this material.

If you have a lot more corn than me you might want to consider buying this gadget.  You can buy the Kleen Kutter Corn Cutter HERE .

Wow! Those are some very interesting ways! I haven’t tried any of those before. Similar to the bundt pan, I’ve used a large bowl to surround the corn during the cutting process.

Because of this, the heat concentrates at the cutting edge of the tool," said Doiron. "This is where the geometry of the tool plays a big role in its ability to absorb that heat and chip away the material. Also, when working with cobalt chrome, establishing proper cutting parameters is vital to prevent tool failure."

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I know it isn’t corn season but everything I harvest somehow ends up in the freezer.  As I was purging the freezer, I realized I had over 50 ears of corn stuck in a bunch of different places.  How the heck was I going to cut the corn off the cobs to make room in the freezer?  Cutting the cobs one by one was waaay to tedious and hard.  So, enter the bundt cake pan.  Learn how to cut corn off the cob with the aid of a bundt cake pan.

Emuge’s TiNox-Cut product range consists of submicron grain carbide end mills for difficult-to-cut materials, particularly aerospace materials. Photo courtesy of Emuge.

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Adding to the fact that this material is difficult to mill, the hard spots also can lead to inconsistent machining results. According to Cory Cetkovic, product manager, Big Kaiser, Hoffman Estates, Ill., it is important to take note of these hard spots in the material and determine the most appropriate tool to handle a range of hardnesses within the material.

"Enhancing the efficiency of machining cobalt chrome can be accomplished by keeping a close eye on the tool life, for all the tools in the process, and frequently changing tools to ensure that you are cutting the material and not rubbing the material with dull tools," said Foschaar. "Most times cutting parameters are drastically reduced in this material to avoid poor tool life, but there is a fine line or small window to machine within for cobalt chrome."

Anna Hackman is the editor of Green Talk, and owner of The Naked Botanical and a avid (okay obsessed) gardener. She also loves video and podcasting and hosts Green Talk TV and Green Talk Radio. Her most important role is being a mother of four boys.

Beyond these characteristics, cobalt chrome is heat-treatable, not magnetic, offers good hot and cold formability, and has high coefficient of thermal expansion and very high resistance to acid, making these alloys a great fit for dental equipment, medical tech, the energy sector, chemical industries, and aerospace.

"We also tend to see some variability when it comes to coolant delivery," said Cetkovic. "We’ve also seen a large number of cases where customers are dry machining these materials."

"This in turn causes the next challenge, which is work hardening of the material," said Foschaar. "These challenges can be minimized by selecting the proper cutting tools for the application."

Cetkovic added that operators need to be aware of the high work-hardening rate of this material. He suggests that a slow feed rate, although better for cutting tool life, could also result in this work hardening, so it’s important to discuss with cutting tool manufacturers the range of cutting speeds (SFM) that the tool can handle in the material. To extend tool life, he also recommends a low depth of cut.

But first things first.  Just to give you a frame of reference, this corn was blanched then frozen.  I defrosted it before attempting to cut off the kernels.  The cobs were a little soggy.

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Another significant consideration is that cobalt chrome is very heat-resistant with low thermal conductivity. During cutting of standard steels, heat generally is evacuated through the chip. However, with cobalt chrome, heat does not generate into the chips.

Manufacturers in the orthopedic and dental implant sectors are familiar with difficult-to-machine materials like cobalt chrome. These superalloys are known for their biocompatibility, making them a great choice for medical device manufacturing. Even the aerospace industry has taken note of the unique characteristics and high degree of hardness that cobalt chrome offers. As this material becomes more mainstream, machine shops have to adapt to meet the challenges when milling this hard-to-cut material, particularly because the cost of cobalt chrome is quite high.

There are several challenges that operators should be aware of when milling cobalt chrome. The material tends to be extremely abrasive, which causes the cutting tools to dull prematurely and reduces the life of the tool.

He explained that for operators or shops that haven’t come across it or are now just starting to get into it, they may find it very disappointing because of the SFM rating and tool life expectancy. However, once a shop has worked out the correct machining parameters and knows how to approach the material, it can successfully machine cobalt chrome and get the best tool performance.

"We are able to take a lot of our more common tool geometries and apply a special coating or put a radius on the edge to help them perform in some of these more difficult-to-machine materials," he added.

Why do people have to reinvent the wheel to do something simple and quick? I have always used an 8″ chefs knife for cutting kernels off cobs with no trouble whatsoever. Put the fat end down, cut the bottom 2/3 or so, then turn the cob over and get the pointy side.

Horn’s Torus end mill is carbide grade TSCC for machining of cobalt chrome alloys. It comes with a 2- to 5-fluted design with a 30-degree helix angle. Photo courtesy of Horn.

Can you do me a favor so more bundt cake pans  don’t hide in the cabinet anymore? Can you share my post on social media and especially pin it on Pinterest. (Just click the below picture and a pin it button will appear.)

"Tools designed for nickel-based alloys or tools for hardened materials are also suitable for this material," said Foschaar. "Nose end mills or square end mills with corner radii are usually ideal for this material. It’s also important that the tools are sharp. Dead sharp tools should be avoided due to the rapid decline of the cutting edge, which will cause rubbing, and a work-hardening situation will occur."

I tried using a drill based up on the video below but you have to have a special drill bit that I did not have. Some people created their own but I am just not that handy.

If you have tons of corn to de-kernel, the hand held corn cutter is not the tool to use unless you have multiple family members willing to take turns.  (This is not happening in my family–even if I paid them.)

Using the appropriate cutting tools is essential to optimizing cutting conditions for cobalt chrome. According to Cetkovic, one of the biggest cutting tool considerations should be strength of the tool design. He recommends starting with a reinforced shank diameter. Choosing a milling tool geometry with a positive break angle will reduce cutting forces and deflection, which tend to be problematic with this material.

Luminoso has a bachelor of arts from Carleton University, a bachelor of education from Ottawa University, and a graduate certificate in book, magazine, and digital publishing from Centennial College.

This is generally because of the low thermal conductivity of the material. Cetkovic explained that when cutting, the tool will absorb a lot of the heat. Adding coolant as the tool exits the cut can cause it too cool down quickly, which can cause the tool to fracture because of thermal shock. Machining cobalt chrome dry can help operators avoid situations like this.

Lindsay Luminoso, sr. editor/digital editor, contributes to both Canadian Metalworking and Canadian Fabricating & Welding. She worked as an associate editor/web editor, at Canadian Metalworking from 2014-2016 and was most recently an associate editor at Design Engineering.

Part of your issue is that you’re doing this with corn from the freezer. If you’d just cut the kernels off your freshly picked corn and then vacuum seal it you’ll find this a far better way to achieve a good result.

"I think everyone who cuts this material, or at least has been in the industry, understands how difficult it is," said Doiron.

Beyond substrate, geometry, and edge prep, adding a coating can be a big asset. Cetkovic explained that a coating can have a huge influence on chip evacuation, which is extremely important in this heat-resistant material.

Marjorie, sometime my freezer yells at me to stop stuffing it with frozen vegetables. I love to stock up for the winter. Anna

Before I tell you my new magic trick on how to cut the corn off the cob, let me tell you all the different  tools I used before I pulled out the ole bundt cake pan.

Maybe you are no longer using your bundt cake since you are watching your sugar intake or lowering your carb intake. Well, here is a chance to free your bundt cakepan  and give it a new life!

Some of the corn will be inside the hole on your counter-top. Don’t forget to scoop it up when you are putting away your kernels.

Grab a bundt cake.  Notice it has a hole in the middle.  Someone knew you could use it to cut corn kernels. I swear.  They were just waiting for us to catch on.

Doiron added that it’s not just the cutting tools themselves that an operator needs to consider. Having a rigid setup with the cutting tool fully inserted into the toolholder to the maximum depth is an optimal scenario. If an operator can keep the tool engaged in the holder to the correct gauge line, tool wear can be reduced, which is already a significant challenge even without overextending the tool.

Carol, you are right. The kernels were blanched and in the freezer. I will try your idea next year but I am such a klutz with a knife. Anna

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"Cobalt chrome is considered a DTC [difficult-to-cut] material due to its high hardness, corrosion resistance, high melting points, and incredible strength at high temperatures," said Chris Foschaar, application and sales engineer, Horn USA Inc., Franklin, Tenn. Foschaar added that there are many variations of the material, with an average hardness of 40-50 HRC. Depending on the type of cobalt chrome, the material also can carry hard spots throughout upwards of 58-60 HRC.

Big Kaiser’s end mills are designed to increase productivity and meet some of the most challenging application requirements. These micro cutting tools are produced using solid carbide with a reinforced shank to maximize stability. Photo courtesy of Big Kaiser.

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"These materials also can be polished at an extremely high level, which eliminates surface areas where bacteria can form in medical devices," said Dan Doiron, milling product manager, Emuge Corp., West Boylston, Mass.

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Wow Anna. So many interesting ideas. I use a knife, but I’m loving the bundt pan idea. I think I have one collecting dust too!