Shaping the Future: Part Consolidation with MIM

The key to streamlining your supply chain is eliminating risk and minimizing the number of suppliers needed to manufacture your product. Ideally, you want to reduce your assembly costs as well. By utilizing the metal injection molding process to single source your complex components, you can do both.

The metal injection molding process lends itself to complex components and part consolidation that cannot be achieved by any other single process. Sign up for our next webinar and discover how we help customers develop custom materials and solutions by understanding their pain points, as well as:

  • Methods of part consolidation
  • How to eliminate secondary assemblies
  • Risk mitigation
  • Complex component case studies

 

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Shaping the Future: Part Consolidation with MIM Webinar Transcript

 

Taylor Topper, Group Marketing Manager:

Hello, and welcome to today’s metal solutions webinar, Shaping the Future: Part Consolidation with MIM. I’m Taylor Topper, Group Marketing Manager at Form Technologies and your hostess for today’s webinar.

 

If you have joined us for a webinar in the past, welcome back. If you are new to our series, I’d like to quickly go over a few housekeeping items so you know how to participate in today’s event. There is no dial in for this webcast. All of your audio will come through your speakers. All widgets are moveable and resizable on your screen so feel free to organize your console in a way that works best for you.

 

You can submit questions via the Q&A widget. If you have any technical issues, no sound or slides aren’t moving, let me know via the Q&A widget and I’ll see what we can do to trouble shoot. I’d also like you to check out our resource list to your right. You can view additional resources there, our company brochure, get your free copy of our design guide. We also have two new blogposts that are listed there and then a link to rewatch a video that we will be showing shortly.

 

We will be holding a live Q&A session at the end of the webinar, so I encourage you to submit your questions through there to today’s presenter. We try to answer them in the order they come in so be sure to get your questions in early.

 

As usual, the webcast is being recorded so if you’d like to rewatch the presentation or if you missed something you can view the recording from the link that you used to enter the webinar. In just a couple hours, there will also be an email that gets sent to you.

 

This webinar is presented by Form Technologies, a leading global group of precision component manufacturers including three major brands. Dynacast for die casting. Signicast for investment casting and Optimim for metal injection molding. With our world class technology and processes, we can serve any industry and any level of ambition with superior precision components and outstanding part to part consistency.

 

Operating 29 design and production facilities in 19 countries worldwide, together our entire business is focused on delivering the highest levels of quality at scale.

 

Today, we have John O’Donnell from Optimim here to help me today. John has been with the Form Technologies organization for close to 15 years and is currently responsible for global business development, primarily focused on metal injection molding. Prior to this role, John was a senior applications engineer with expertise in product design and development, design for manufacturing, GD&T, and customer service. John, thanks so much for joining us today, a veteran to our webinar series so welcome back.

 

John O’Donnell, Global Business Development Manager:

Thank you, Taylor, for the introduction and thank you, everyone, for joining us today for this webinar edition that we’re going to cover here regarding concepts and ideas on part consolidation.

 

OptiMIM Metal Injection Molding Capabilities

 

Starting with our agenda here, we just want to give you a brief overview of who Optimim is, our Optimim division. Then we’ll get into just a quick overview of our MIM process for those of you who are not quite familiar with metal injection molding and cover a little bit of our materials segment as well and then we’ll dive right into part consolidation, the benefits of that, and help you understand some opportunities or at least allow you to start thinking outside of the box on ways to leverage this metal injection molding technology or ideas, whether it’s solving cost issues, functional issues, performance issues and so on with your either new product or existing products that are out there.

 

Then we’ll give you some success stories based on some case studies that we have with previous experiences so you have some examples of what has worked well and then we’ll wrap up with a Q&A session.

 

So taking a look at Optimim at a glance, give us some idea that within our Form Technologies corporate headquarters, our company, Optimim is our metal injection molding division. We collectively have over 200 years of aggregated experience with our team at hand. That being said, we are one of just a few companies that helped commercialize the metal injection molding industry in the early-’80s. So we have 35 plus years experience and have seen and experienced quite a bit of scenarios and circumstances. You can only imagine for design improvements and products and so on.

 

Another thing to highlight on here is the fact that Optimim does produce 100 percent of our feed stocks in-house, and we’ll talk a little bit about that throughout the presentation, why that matters and how that weighs into part consolidation and product quality.

 

With that, we want to give you just a quick video that provides you an overview of the MIM process. Again, for those of you that are not quite familiar with it or need a bit of a refresher and then we will continue on from there.

 

Video:

Metal injection molding, or MIM, has a well-deserved reputation for delivering the highest performing small precision parts in the metal-forming industry. Its secret, MIM’s unique production process. This achieves significantly higher density than anything possible with standard powder metallurgy. It starts when super-fine metal powders are combined with a primary paraffin wax material and a secondary thermal plastic polymer. The resulting mixture is extruded and chopped into tiny pellets. These are heated before being injected into a mold cavity under high pressure. It is a technique that delivers tighter, net-shaped tolerances over high production runs, making it possible to produce extremely complex components with enhanced surface finishes.

 

Once molded, the component, what we call a green part has an identical geometry to the finished part, what is about 20 percent larger. This allows for shrinkage later in the process. The part is then put into a furnace to remove most of the binders during the debinding process. At this point, it is referred to as a brown part. In the final stage, sintering heats the component to temperatures near the melting point of its metal. This eliminates the remaining binder and gives the part its final geometry and strength.

 

The result, high-precision parts delivering world-leading strength, corrosion resistance, and density. Optimim, when only the best will do.

 

John O’Donnell:

So that just gives you a very brief overview of the process of metal injection molding. Touching on a couple other highlights of this process, aside from the actual process or manufacturing of the parts itself. To give you some idea, where does MIM compete? So what this slide represents is just a representation of annual quantity as a reflection of part complexity. What this implies here is that contrary to conventional thinking that usually when you design a part you think the more complex it is, the more cost is endured, particularly with say like machining because you have more process steps, more setups under CNC in order to produce those features.

 

Part Complexity and Reducing Cost at Scale

 

On the other hand, with metal injection molding, as the part gets more complex, it has to do really more with the capital investment or the molds that are used to produce the part because that’s where the geometry is produced. Therefore, MIM tends to be more cost effective as you get more complex on the components.

 

On the other hand, with the annual quantities, what drives the MIM process in terms of higher quantities there’s two aspects to this. One is for metal injection molding, the higher quantity because this is a batch-driven process. You’re typically loading parts into large convection oven batch furnaces and that’s what determines, typically the lot size. So the higher annual quantity the better for this process.

 

The other part of that is it makes it scalable as well relative to costs. What I mean by that is typically you can go from, say, a few thousand parts a year to start up to several hundred thousand parts a year or million parts a year with far less investment than you would with, say, machine centers utilizing the same footprint. So this process is very scalable to get to very high volumes very quickly.

 

Aside from where does MIM compete, where does MIM fit relative to other technologies out there. So really MIM or metal injection molding is a niche technology that is a solution technology, that’s a solution to a problem. Whether you have a component that may be plastic and it’s failing or not performing to standards and you need something stronger and machining components that are particularly complex may be too expensive. The metal injection molding might be a solution to fit that void or that niche to solve some problems cost effectively so you can solve your functional issues and perhaps your cost issues collectively. But this is just some examples of where this technology fits in the scheme of things.

 

In short, MIM really is kind of a fit between solving the cost problems, particularly if you have an extensive machine part and you want to convert it to reduce costs but you don’t want to give up the function. This is the way to do it here. You’ll see some more examples as we go through these slides.

 

Metal Injection Molding Custom Feedstock Materials

 

Talking about metal injection molding material options, some of you may be familiar with MIM and some of you may not be but metal injection molding materials are typically ASCM type metal that we commonly use. The idea is that anything that you can produce in a bar stock or source in a bar stock can be done in MIM. So we do stainless, carbon steels, a variety of other things that can be done, and you can get into not just ferrous and non-ferrous but tungsten alloys and cemented carbides and so on. So there’s a variety of materials.

 

The other benefit to metal injection molding materials, and the fact that we also produce our own in-house feed stock, which I the outcome of this material is that you can actually blend custom alloys or special alloys to get unique properties that are not attainable in off-the-shelf material today. So that’s another side benefit of considering metal injection molding, whether it’s either individual components or part consolidation.

 

For material performance, again, we produced our in-house feed stock of our own materials of any particular grade. In this particular slid here represents a 17-4 pH material and what it shows is just our mechanical performance and our ductility. In other words, elongation relative to the industry. The metal injection molding industry, managed by the MPIF develops industry standard for metal injection molding industry. As you can see from Optimim versus the MPIF standard typical 35, which is the industry typical average for metal injection molded materials and then the minimum standard, which is the low end of the spectrum. So you can see there’s a wide range of distribution in material performance.

 

In Optimim, blends their own materials and we always strive to exceed, widely exceed the standard out there and particularly for higher elongation. The higher the ductility allows for better part integrity.

 

So aside from some of these overviews of the process and the materials and so on, the materials can be looked up on our website at Optimim.com as well. There’s a variety of materials that are listed with all the mechanical properties and chemistry and so on and that is available. Moving on to part consolidation, the core of this webinar that we have today is to really give you some points to consider or get you to start thinking outside of the box on how to leverage this technology to consolidate components. What I mean by that is that typically working with most customers and an engineer, I’m a design engineer myself by trade. You typically think of looking at components, right. You look at it component by component basis. It’s the assembly and rather than just focusing on the component level is best to think on the assembly level. This is an example of where you have multiple components that might be sourced.

 

You have a stamping, a CNC part, you’re sourcing a pin with an e-clip and so on. So eventually you might think how could I reduce this component cost and still maintain the form, fit, and function of the part without sacrificing any integrity or quality of the design. One of the beauties of metal injection molding, as I mentioned in an earlier slide is that complexity really favors this technology because the complexity is driven into the capital investment or the mold itself.

 

Mitigating Risk with Part Consolidation

 

So as you can see on the right, you can actually take multiple components that are sourced and consolidate them into a single MIM component that meets the functional intent and you eliminate quite a bit of assembly cost. You eliminate the risk that comes with assembly failures, also an opportunity to…by assembling components or by removing the assembly process not only are you saving costs but you’re also eliminating the tolerant stack up conditions that you might experience with design components. That way you don’t have to deal with the tight tolerances or over-designing or over-tolerancing components. Jut combine it into a single product.

 

This can also drastically reduce your supply chain without sacrificing the function as well. As we know, the world we live in today being competitive and reducing your supply chain is something we hear quite often and this technology really allows you to capitalize on that.

 

That ties also into the risk mitigation aspect of this. There’s certainly a lot of risk with supply chain. You’re sourcing different components from different suppliers all around the world perhaps. That represents a lot of components that are in the supply chain and that puts things at risk. So if you have changes in your demand or you have a supplier that has a particular challenge that puts you at risk of going ______ 00:16:16 down there’s a way to consolidate these parts and consolidate your supply chain. That’s really the message and the takeaway here.

 

Another opportunity to mitigate risk is by reducing product failures and improving your product quality. Again, by part consolidation you’re reducing that potential risk or that failure mode of those assemblies as well. So anytime you have a component that gets assembled, whether it’s mechanically assembled or welded or something like that. There’s always a risk associated with that. So combining components helps you mitigate that risk considerably. We have some case studies here that we’ll show you that make reference to that.

 

Ultimately, by mitigating risk and managing your supply chain that also has an opportunity to minimize your field failures and field returns and improve the product reputation and quality. So this could actually give you not only short-term benefits in cost savings and consolidation but long-term benefits in the reputation of your product the reduction in field returns and hopefully driving up the bottom line revenue of your company.

 

Another benefit of using metal injection molding and part consolidation is not just the short-term benefits and the opportunities but also the long-term quality, as I mentioned. One of those that is quite common with assembled components is the residual stress that gets built up in the parts. The thing with residual stress is that typically while you try to mitigate it when you’re designing your assemblies and your components all processes or many processes out there like CNC, stamping forging, welding, and so on all induce stress within the part, and you can’t see that until it fails. That failure might be a field failure of a product or something worse. So mitigating that risk through metal injection molding is one way to do that. The reason we say that is that MIM, being a net-shaped technology for molding components, even into an assembled component that you might have to make an assembled geometry in MIM, you have far less residual stress by doing that and that reduces your risk of product failure.

 

Considering other concepts as well, when you look at part consolidation you think of also ways to reduce cost and one of those might be weight. Metal injection molding benefits greatly by what we call coring parts out or reducing mass. As you can see from the left to the right, the solid part that might be machine and assembled you could actually core that out, get a uniform wall thickness, which benefits metal injection molding but it also reduces weight and weight equals mass and mass reduction equals cost reduction because you have less material in your injection molding but you do this without impacting your form, fit, function of the part. Again, aside from part consolidation you can reduce weight and mass and cost.

 

Taking advantage of this technology, too, it’s not necessary having to do press fit assemblies were conventionally you’ll take a round pin and try to size it accordingly and do your tolerance stack ups with a press fit hole but there’s other ways to leverage metal injection molding because when you look at an opportunity to assemble components, press fits can always be a challenge. Either you have high yield loss or fallout because you have something that is toleranced a little bit too tight or you have just enough variation that some of your assemblies will actually have a loose fit and fall apart. Some will be over-stressed and cause residual stress on the part in tracking and one way to solve that with MIM is to be able to not only just think outside the box and look at not just a round hole to a round pin assembly but you can act use round pins and use square holes in MIM and allow you to produce a four-point contact. Effectively, crest points and that really takes a lot of variance out of your assembly and your tolerances.

 

You can actually loosen up your tolerances on your pins and your assembly here and get more consistency in terms of the press fit and the forced retention. This is another creative idea to take advantage of this technology as well.

 

Weight and Cost Reduction with MIM

 

As I talked about, weight and cost reduction. I talked about coring and other things like that. For metal injection molding, again, what this represents here is just a function of cost relative to complexity. So again, as the part increases in complexity typically that costs more by many other processes, whereas metal injection molding tends to be more ______ 00:21:44 cost because your complexity is in the capital investment. That’d be in the tooling and not so much in the part price. What drives part price is really the amount of material and then any additional secondary operations that are required in order to meet feature tolerances that cannot be achieved by a net-shaped part out of the furnace. So again, there’s a lot of different creative ways to work with you on your product to do that.

 

Looking at conversion, not just part consolidation but conversion from other processes, machining is probably one of the prevalent benefits of using metal injection molding with complex parts. It’s being able to take not only machine parts and convert them to MIM but combine the geometries to get a more complex part that in this case is actually nearly impossible to machine but with complex tooling and metal injection molding process you can get a net-shaped part that not only reduces cost but you combine components to eliminate the assembly risk if you will.

 

A way to take advantage of this is whether you have new components or new product that you’re looking at or even an existing product for conversion. There’s ways to take these parts and combine them and also by doing this here, by making this conversion and consolidating parts you might ask some questions like I have a couple different materials that I want to combine. The benefit of combining into metal injection molding is you can go to one material to give you the mechanical performance you need but you also eliminate the risk of corrosion and dissimilar metals. There’s a lot of different benefits that can be had by consolidating. It’s not just assembly. It’s also material, corrosion, corrosion stress cracking. There’s a lot of things that need to be considered here as well. Combining that allows you to scale up quickly as well.

 

Early Supplier Involvement for Product Design

 

So some takeaways from all of this that I’ve covered here today is really but early involvement. So no matter what stage of the product design or development you’re in it’s just considering early involvement with us or metal injection molding to understand how we might be able to help you remedy both cost, function, quality, materials. There’s a lot of different aspects that you’ve seen today that allow us to try to help you. We have, again, 35 plus years experience as a company and we’ve seen a lot of different things that we might be able to bring to the table and help solve some of your challenges there.

 

These other takeaways here are looking at time to market. It’s an opportunity to consolidate resources, reduce your supply chain and get to market quicker leveraging this concept. If you’re already in the marketplace, certainly, looking at your product or performance challenges. What are some challenges that you’re having today in the marketplace with your product and kind of ask yourself some of those questions? Could this be a solution to solve some of those challenges? Whether it’s a full assembly or a subassembly of various components. There’s ways to look at that and take that approach. So that’s what we’re here for is to help offer you some guidance and some advice on how we might help with that.

 

So looking beyond the component itself, again it’s the cost, it’s eliminating the cost, the risk. We talked about risk of assembly, failure moments. Residual stress, there’s a lot of variables to be considered in here. Some of them are seen and observed and some are unseen until sometimes it’s too late.

 

Again, taking advantage of targeting, weight reduction, improving your performance or at least maintaining performance without sacrificing the function of the part. You can reduce the weight. A lot of different things you can do there. And of course short-term. Not only is there long-term but there’s the short-term opportunities as I mentioned to consolidate. The supply chain which consolidate cost so that way you’re not looking at just the individual component. You’re looking at the total cost of that assembly at the end cost of your product.

 

At the end of the day, we all want great products, right. We’re all consumers out there on the marketplace buying different products. One of the worst things we deal with is having to return something to a store because it failed and field returns. So that being the case, what I want to do is take you through some case studies of what we’ve done for some examples in the past and how this technology and part consolidation has helped the customer solve these challenges.

 

MIM Part Consolidation Case Studies

 

This is one example here of a component, which happens to be a water lever. This is something that most of you might recognize from a soda machine. So you look at the water lever, this is actually a stainless steel single MIM component that was combined from three different components. It happened to be a machine part, a stainless steel kind of a bent rod if you will and then there’s the face where you see the water sticker that is put on there. That was actually a stamping. So those three parts were previously produced and assembled by welding. It was very expensive. There was obviously looking at different ways to either do a plastic injection molded single piece, which failed.

 

There was a number of different failures and the result was being able to go to metal injection molding on a stainless steel single component and not only was there just a cost savings in doing this but there was a tremendous reduction and field failures. As you can imagine, people pushing on this water lever you get all kinds of kids and adults that tend to be in a hurry or something and they’ll push on that lever and historically snap that right off. This reduced the field failures tremendously and increased the reliability. So that was a great story about part consolidation.

 

This is another example of a past customer that does allow us to use their name, which is DeWalt Black & Decker. They came to us years ago with two machine components that they were looking to cost reduce. A way we took advantage of the technology was taking their 3D models and actually combining them into a single model to eliminate that assembly, which is a cost reduction. Unbeknownst to them, what they didn’t anticipate was that their field failures and their product returns to the store dropped dramatically.

 

So while the initial intent was to reduce machine parts in cost to MIM parts by consolidating, they eliminated not only the cost of the assembly but they dramatically reduced their failure modes in the field of the product. This assembly actually followed a part.

 

Then the last example I have today is another product here where this was a customer that used a stamping and then they used some machine components and then they over-molded it with plastic injection molding. It had all kinds of challenges with it. It wasn’t just mechanical failures. They also had some thermal and heat dissipation issues that they couldn’t solve.

 

So what they did was they took the stamping, the machine part, and the plastic injection molded, over-molded with plastic and combined them into a single stainless component and the benefit of that is not just eliminated the assembly in the supply chain that they had to deal with but it also solved their heat dissipation issues by going to a single material that could dissipate the heat much better than an over-molded plastic component. So that was one example of how to leverage that as well. So that being said, that is some examples I wanted to take you through and allow you to kind of think outside of the box on how to leverage this technology for part consolidation but also give you some real-world examples of how we’ve helped provide some solutions to some of these challenges. So with that said, that’s all I have here today and we look forward to taking questions.

 

Frequently Asked Questions

 

Taylor Topper:

Thanks, John, so much. We do have quite a few questions in and just to let everybody know, we give a full hour for the webinar but we’ll just keep answering questions until we run out. I am going to start with one of the first ones we have here. Are undercuts possible in small parts?

 

John O’Donnell:

Yes, they are. That’s a great question actually. With undercuts, we do have parts that we have made in production for years that have undercuts in them. So you can use, typically, a collapsible core in your tools to be able to produce that. But again, it’s geometry dependent and where it is, but yes, it is possible and we do it today.

 

Taylor Topper:

Great. Does part consolidation introduce added cost to a project?

 

John O’Donnell:

That’s not the intent. By part consolidation we want to try and reduce your cost. When you look at the total cost of that product it’s not just looking at the parts and adding them up to compare to MIM. It’s what is the total cost savings? You eliminate assembly cost and then you also could improve your product yields in your manufacturing plant as well as reducing your returns or your product failures in the field, so it’s looking at the total cost.

 

Taylor Topper:

Starting with the earliest concept of the design process, how are prototypes made with MIM and what is the cost?

 

John O’Donnell:

The prototypes with MIM, they are production representative parts in terms of the material quality. We don’t take any exception to producing prototypes using a different or unique material. We use production-grade materials and we do prototype with conventional tool steel in a single cavity. That way we’re not trying to translate from a unique prototype process into production. We are doing production representative parts at the prototype phase use of conventional tool steel inserts.

 

As far as the cost is concerned, that varies widely on the geometry. There’s some customers that like to prototype near net-shaped parts with a very cost effective single cavity insert and produce a net shape. There’s others that really want production representative tolerances and that would require us to do secondary operations in order to meet some tolerances, so that really runs the gauntlet. The cost is hard to pin down and it’s a case by case basis.

 

Taylor Topper:

How is MIM performing versus 3D printed metal components in terms of cost and quality?

 

John O’Donnell:

Speaking of…compared to 3D printing as far as MIM parts are concerned, you tend to have higher mechanical properties with those because we have very, very low porosity. We’re talking two to three percent non-interconnected porosity in our components. So again, the MIM parts do represent generally a higher strength, but again there is so many different technologies out there in 3D printing that add a wide variance to that. As far as the cost of 3D printing, as some of you may know from experience in that, getting a handful of parts produced by 3D printing can be very, very expensive compared to MIM where we can MIM 20 parts up to a thousand parts or more with the same tool rather than having to print a single part at a time.

 

So by and large from my experience MIM can certainly be more cost effective per part in prototyping than what you would find with 3D printing but again, it’s very geometry dependent.

 

Taylor Topper:

Great, John. I think this came in a little bit earlier in the presentation but could you elaborate again on how part consolidation helps to manager tolerance stack ups?

 

John O’Donnell:

Yeah. So when you talk about tolerance stack ups, say you have four or five different components and you have to tolerance those parts very tightly. In other words, let’s say you have five different components that have a tolerance, a plus or minus one thousandth of an inch on there. All of a sudden, now you have a total tolerance stack up of ten thousandths and variants plus that you have to deal with. By consolidating components into a MIM component you effectively reduce that tolerance stack up so that you’re looking at the individual component, what was the assembly previously and it minimizes your stack up and it minimizes your variants because you have consolidated parts and that’s what we’ve experienced on a number of programs.

 

It also eliminates the variation that you might find as well. When you have tolerance stack ups you have some parts, you may have some assemblies that assemble very tight and some that are very loose and loose assemblies can fail just as easily ones that are too tight and induce residual stress. So combining the assembly into MIM can certainly eliminate a lot of those variables or at least really reduce it.

 

Taylor Topper:

Next question here is the powder metal used in 3D printing the same as the powder metal used in MIMs?

 

John O’Donnell:

I don’t have direct experience with that, but I have certainly had my ear to the ground with the industry and what’s going on and what I can tell you is that the MIM powders that we use typically tend to be much finer than what you see out there in the industry. But again, there are so many different types of 3D technologies out there. 3D printing is kind of the Wild West. Everybody is doing something quite different from one another so they’re using several different powder sizes. But by and large, MIM tends to be a smaller band and smaller particle size, which gives you some better surface finishes than what you’re going to find with 3D printing usually.

 

Taylor Topper:

Thanks, John. Kind of along the same lines here we’ve got a couple questions based around materials, but I think this one…how does Optimim’s feed stock differ from BASF?

 

John O’Donnell:

The big takeaway for us is that by being able to develop our own feed stock we control all the variables in the process. As I mentioned, in one of my webinars in the past that Taylor and I have put on, it’s called MIM 101, which is available on our website and our webinar series as well. I talk about the materials itself and the fact that by producing our own feedstock we can source the metal powders, the distribution size, the binder system, all of that and control the variables because feed stock is really the foundation of the MIM process.

 

That being said, MIM being a process-intensive technology, all the downstream processes only add a little bit of variation to the end result, the end part in terms of tolerances. So we control those variables and by having a tighter mix or a more consistent mix we get more consistent results. It’s really that simply put.

 

Taylor Topper:

Next question here, can you use aluminum alloys for MIM?

 

John O’Donnell:

You can. That’s been more of an interest. We’ve had more and more interest in that tier recently. But you can metal injection molding aluminum materials. Typically, the challenge that you have with it is it just has such a low melting point that it might represent some additional challenges at the sintering phase where we’re sintering the geometries. But it can be done. There could be some benefits compared to other technologies out there doing that. Good question, though.

 

Taylor Topper:

What size range, dimensions, and weight would be good for the MIM process typically and are critically rotating parts good for MIM?

 

John O’Donnell:

As far as MIM component size, we kind of crudely refer to it as anything you can hold in the palm of your hand or fit into a traditional size coffee cup. That or smaller is typically what works best in the MIM space as far as component size. That really has to do more with economy of scale more than it does just the technical aspect of it. I think there was another part of that question, Taylor, too. What was the last part of that?

 

Taylor Topper:

Yeah. Are critically rotating parts good for MIM? Critically rotating.

 

John O’Donnell:

Yeah. The benefit of MIM is that metal injection molding parts actually exhibit the same or very, very similar performance to wrought metal or machine parts and so anything that you can do, any application that you can apply to a traditional machined or steel part you can apply that to MIM as well. If you look at our mechanical properties on our website and compare it to wrought metal and with our very low porosity you can see that they would perform equally well.

 

Taylor Topper:

Next question here is in regards to tooling. Do you build your tooling or molds in-house in the States or offshore?

 

John O’Donnell:

All of the above. We actually have in-house tool shop that we do primarily for in-house maintenance and repairs. Some low builds and then we also source some molds outside as well. The reason for that is because there’s so many different geometries out there and so many different ditch experience and knowledge and capabilities that other mold makers have that we really have a portfolio that we source from so that we can produce just about any geometry and leverage any talents that are out there.

 

Taylor Topper:

We have quite a few questions regarding the presentation and sharing it afterwards. So just to remind everyone, this is being recorded and it will be sent out after the webinar is over. It usually takes a couple of hours for the video to propagate and then you’ll get another email reminder with the recording and that will have all the slides on it as well. Let’s go to this next question. What is the benefit of MIM versus zinc or aluminum die casting?

 

John O’Donnell:

I think the main benefit there is not just surface finish but also material strength. Just the mechanical properties are certainly higher and again closer to wrought metal. Those are the simple answers. Again, it’s just looking at your application.

 

Taylor Topper:

Next question here, can you make a consolidated moving part like a hinge?

 

John O’Donnell:

We have…as I think back to my history with Optimim, we’ve actually done some examples of that where you can produce a component and provide some sort of a breakaway but again it is very geometry dependent on doing that. It’s not quite as practical as what you might find with, say, 3D printing where you can obviously produce 3D printed, moving components. The reason for that is that MIM parts, when they are molded and then produced and then loaded into our de-wax and sintering ovens they do shrink about…depending on the specific grade of material, 18 to 20 percent, and so there’s some factors that we have to consider there as well. But we have done that sort of technology before and interested to look at your application.

 

Taylor Topper:

How does part consolidation affect tooling?

 

John O’Donnell:

The impact on tooling really has to do with complexity. The more complex the tool is we just have to look at where are the critical seal-offs and do we have any high-ware features in the tool that we might have to provide inserts for. We certainly have a lot of experience in doing that. If there’s particular intersections or cores that come together in a tool or a seal off that represents a challenge we have replaceable inserts for that feature, we’re going to have that discussion with you up front. We compensate for that. That’s what allows us to get, in most cases, several million shots out of our tools.

 

Taylor Topper:

Can you consolidate a part with two dissimilar materials?

 

John O’Donnell:

You can. It’s called co-sintering is what that’s called. You can do that. It depends on the grades of material and also the geometry is of how they interface or interlock together because you have to produce a similar shrink rate for both of those materials, but it is done in the MIM industry and it can be done. Again, it’s just geometry dependent.

 

Taylor Topper:

Do you only offer thermal debinding or is solvent or other types available?

 

John O’Donnell:

There’s a number of different types out there. We choose to do thermal because it’s repeatable, predictable, and we’re not at the mercy of any chemicals. We don’t have to handle the chemicals and we don’t have to worry about the EPA coming down the road and telling us that that chemical is banned and have to reformulate our process. So thermal is predictable and sustainable and of course it’s a green technology. It doesn’t involve any waste.

 

Taylor Topper:

John, what are typical tolerances of MIM?

 

John O’Donnell:

That’s a good question. One thing I will share is that when it comes to tolerances of specific features and geometries, we have an in-house tool that we analyze on a feature by feature basis and talk about tolerances and capabilities by feature. This is something we developed years ago to do that but for rule of thumb and designing purposes, ideally plan for…what you should plan for is about plus or minus five thousandths per linear inch of dimension but typically to get to the ideal state you can get as close as plus or minus three thousandths per linear inch in many cases.

 

Then isolated very small features we can even do better than that but that’s just a general rule of thumb. Again, for us to analyze your component on a feature by feature basis because of all the variables that come with MIM process we can provide you an analysis.

 

Taylor Topper:

Piggybacking off of that, are tight toleranced threads possible with MIM?

 

John O’Donnell:

Yes, they are. You can actually get…we produce both external and internal threads. You can actually mold those. Internal threads can be done if the cost and the process and the demand makes sense. You can actually do unscrewing cores for internal threads and mold external threads. Because this event is recorded and you watched the video, the video that we show on the metal injection molding process actually shows a couple of components with an internal and external thread and that is something that we’ve produced before as well that were both that shape and threaded together very well.

 

I think that was actually a quarter inch by 24 pitch thread, if I remember right on that part. It’s been a while. Yes, you can do that.

 

Taylor Topper:

How much draft is required with MIM if any?

 

John O’Donnell:

Yeah. Great question. Part of the conversion from other processes or technologies to MIM is that in most cases we don’t require any draft. There might be some few exceptions where we have a very long pull or a high aspect ratio of feature where we might induce maybe half a degree of draft just to provide some additional relief to eject from the mold, but in most cases we don’t require it.

 

Taylor Topper:

I’m sorting through a lot of questions on tolerance, but I think that you have answered most of those.

 

John O’Donnell:

Yeah. Part consolidation.

 

Taylor Topper:

What’s the thinnest wall typically?

 

John O’Donnell:

The thinnest wall in production with a larger surface area, the thinnest wall I’ve seen sustainable and repeatable in production might be pushing 12 to 15 thousandths of an inch in wall thickness. You can certainly do a little thinner in isolated areas but with larger features. It’s about 12 to 15 thou is what I’ve seen. Again, let’s look at your application and figure out what feature size you’re talking about.

 

Taylor Topper:

Is micro molding feasible with metal?

 

John O’Donnell:

Yes, micro molding is done out there today but micro molding is a little bit of a loose term as well. Everybody has a different interpretation of that but typically if you look at micro molding it’s typically a part that might be the size of a grain of rice or even potentially smaller than that. So it can be done. It just depends on, again, the geometry and the materials. It’s a special application in metal injection molding but yes, it can be done.

 

Taylor Topper:

I think this next question the answer is going to be one of those depends on the complexity but I know that cost obviously is important to most of our listeners. So is there a good rule of thumb for cost per pound, I’m guessing, that can be used to approximate piece part price?

 

John O’Donnell:

I would say no to that and the reason I say that is because the material costs are very small. It’s typically a fraction of the total inherent cost because you not only have the cost of material, you have the cost of the debinding, the sintering, the secondary operations, and so on. There’s a lot of total inherent cost in the process and so you can’t necessary equate the cost of the material to the cost of the part. It’s not linear by any means.

 

Taylor Topper:

How long did it take to develop the process for a new material?

 

John O’Donnell:

It depends on the type of material. If you get into some sort of tungsten alloy or a cemented carbide or something like that that’s certainly going to be a little bit longer than it would be to come up with something in the ferrous or non-ferrous alloy phase but as far as timeline is concerned it depends on, again, the material and the application. To give you some examples, what I’ve seen in my career, I’ve seen us develop materials for some applications in just within a few months and there’s some very challenging applications and challenging materials that have taken us six plus months to do. Again, it depends.

 

Taylor Topper:

What are typical defects with MIM parts?

 

John O’Donnell:

Metal injection molding, being a hybrid technology between plastic injection molding and powder metallurgy, a lot of the defects that you might find potentially in a MIM part would emulate that of, say, plastic injection molding. So parting line flash, areas where you might risk of having sink of a thick to a thin section, flow lines at the gate, things like that. Very similar to plastic injection molding.

 

Taylor Topper:

Does Optimim have any experience with compressor ______ 00:53:28 or impellers utilizing the MIMs process?

 

John O’Donnell:

Yes, I’ve had some experience myself with that in the past and produced components. The advantage of doing that is that you can actually come up with ways to not only leverage the material that we have but actually make some potential improvements to the design of the part that might seem more complex to you but actually promote the MIM process to give us some additional performance enhancements.

 

Taylor Topper:

When threading the outside of a tube, how thin can the tube be?

 

John O’Donnell:

That probably goes back to the thin wall application. What we do is by doing a mold flow analysis, the geometry, we can kind of tell you what we can fill for geometry and how we vent it and so on. But again, if you’re going to use a rule of thumb I would say consider 12 to 15 thousandth of an inch wall thickness as a general rule, but again allow us to look at your application and run a mold-flow analysis and determine what we can do at that feature.

 

Taylor Topper:

Great. The last couple of questions I have here seem very specific to a certain project. So I’m actually going to follow-up offline with these. John, thank you so much for presenting for us today. Like always, you always do a wonderful job. Thank you to all of our attendees. Look for that recording. It’ll come through your email. If you have missed other webinars, Optimim.com in our knowledge center you can find our webinar page there and have access to a variety of different webinars. We host a webinar, Form Technologies does, once a month either for Optimim, Dynacast, or Signicast and all of those do live on the brand website. So take a look at those and if you do have any questions feel free to reach out or topics that you’d like us to cover. We’re always looking for new topics and content to share with the masses. So thank you, everybody, and thank you, John.

 

John O’Donnell:

Thank you, everyone, for your time today.

 

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Last updated 07.30.2020