Automating Medical Device Molding: From First Part to Lights-Out Production
Chapters:
00:00 Welcome and Introduction
01:18 Automation as a Lifecycle
02:10 Introducing Nissha Medical Technologies
04:30 MTAP, DFA, and OEE Framework
07:39 Defining Requirements for Scalable Automation
11:20 From Manual Assembly to Lights-Out Production
20:46 CTQs, Inspection, and Process Monitoring
24:59 Micro Molding Challenges and Precision Manufacturing
36:22 Injection Molding Automation Strategies
47:52 Post-Molding Automation with MMT
54:36 Upcoming Events and Thank You
00:00 Welcome and Introduction
Steve Maxson
Hello everyone and welcome to the Chamfr Webinar Series. Today’s session is focused on automating medical device molding from first part to lights-out production. I’m Steve Maxson, and I’ll be moderating this discussion. This webinar features Nissha Medical Technologies with insights from their experts in automating medical device molding.
It’s sponsored by our partner MMT, more on them a bit later.
Some quick housekeeping. This session is being recorded. The replay will go out to everyone shortly after we finish. You will be muted. The chat will be off, but please drop your questions in the panel. Before we dive into the discussion, I’d like to introduce you to our Chamfr partner, MMT, specialists in precision medical manufacturing solutions, from cutting tools like you see right here to catheter manufacturing equipment, grinding technologies, and integrated automation solutions.
01:18 Automation as a Lifecycle
Steve Maxson
Let’s get started. Really excited to talk about automation with Travis and Vijay. What I’m really excited about in this conversation is not just a pick-and-place machine or a robot or software.
It’s about looking at automation as a lifecycle, and then talking about different ways and metrics, tools to monitor and look at the repeatability of automation. So guys, I’m really excited to have you on today. Why don’t we go with some quick introductions? We’ll start with you, Travis.
Travis Garrison
Yeah. My name is Travis Garrison. I’m the Global Automation Manager for Nissha Medical. We’re primarily based here in the U.S. My group focuses on taking customers from the very beginning of a concept all the way through their lifecycle. So as they grow, we grow along with them in capability. My group is really focused on riding that journey with them and getting to the finish line.
Steve Maxson
Excellent. Thanks, Travis. Vijay, it’s nice to have you on again.
02:10 Introducing Nissha Medical Technologies
Vijay Kudchadkar
Yeah, thanks for having me on, Steve. I’m Vijay Kudchadkar, Director of Plastics and Sales Engineering at Nissha Medical Technologies Isometric. I’m a plastics engineer with about 20 years of experience in precision injection molding, and eight years of experience in extrusion, thermoforming, and blow molding.
I work with our team to find solutions for customers, enabling medical device technologies as well as cost reduction.
Steve Maxson
Excellent. Yeah, it’s good. I worked with Travis on MPP West last year and Vijay at MPP East, and now Vijay is going to be heading up a miniaturization panel at MPP West coming up in April.
So it’s good to reconnect with you guys. The content and the discussions in the past were really great, so I think the audience will find this very informative. Vijay, do you want to talk a little bit first, give an intro to Nissha Medical Technologies, and then we can move on and talk about automation?
Vijay Kudchadkar
Sounds good. Yeah, so as we said, we’re with Nissha Medical Technologies. We are a global CDMO, working with leading medical OEMs as well as startups, helping them all the way from concepts to contract manufacturing, all the way through full device assembly. We have multiple sites across the world, primarily in North America, Dominican Republic, Europe, and Southeast Asia, where we have state-of-the-art manufacturing and design facilities.
We also specialize in enabling technologies such as surgical navigation and surgical robotics, sensors, electronics, endoscopes. And Nissha recognized the importance of micro molding for miniaturization and acquired Isometric Micro Molding to help medical device OEMs achieve their goals.
In the next few slides, Travis will be talking more about automation, and then I’ll come back and talk about automation specifically for injection molding. So take it away, Travis.
04:30 MTAP, DFA, and OEE Framework
Travis Garrison
Excellent. Thanks, Vijay.
Perfect. So the way that we approach automation is we use this process called an MTAP, and that’s the Manufacturing Technology Assessment Process.
And while we use a whole bunch of other tools in the quiver, like Agile, Scrum, and some of the other ways to take a project from start to finish, I really want to focus on MTAP, DFA, and OEE because at the end of the day, and a lot of us engineers have heard it, if I give you a bag of money, how are we sure we made a smart business decision?
A lot of times that stress from finance, stress from the executive team, are we going the right direction? Why are we investing this much? So really what this is, is a framework to create forward thinking and to start putting some checks and balances in early in the process. So as we start progressing and maturing with the customer, we can actually provide the product they’re looking for at the rates and price point they are as well. So as we go through this, we start early in the process. We’re at the concept where the MTAP is discovered. We start getting into the DFA all the way through optimization and growth. And one key thing here is we don’t think of automation as a single project.
That’s kind of been the stigma for a lot of years. We think of it as a lifecycle decision that starts at concept through stabilization. Go ahead and go to the next.
MTAP. So again, it’s the Manufacturing Technology Assessment Process. This is not a hard procedure. I’m not telling you this is the way that we have to do it, but what it is, is a framework, and when you’re talking with the executive teams, finance teams, that’s the type of angle that we have to be viewing these projects in.
It is not a gate function. There isn’t something that says, at this point we’re going to trigger it. No, it’s me sitting down with the team, looking at the customer design at the beginning, going, okay, we’re going to enter in here, but as we progress, we’ve got to get to here. What does that path look like? It may not be fully defined. We might not have every answer to get to the endpoint, but we start asking those questions, which starts defining our approach to it.
So again, it’s introduced early in the concept and quoting, not after problems show up. Granted, it does happen at times, don’t get me wrong, but we try to do it as much in the foreground as we can, and that path and direction is the big thing.
As volumes increase, risk starts showing its head because there’s variability that we didn’t foresee in the beginning or the complexity starts changing drastically. And especially in micro molding, flashing something super small can turn into a huge mountain of problems. Also through this, we’re looking at the system. Can we reuse this down the road? And are we just creating a single instance of a machine, spending all these resources and time? No. How can we utilize this across multiple platforms?
07:39 Defining Requirements for Scalable Automation
Steve Maxson
Travis, quick question. On the early DFM, when you’re working with a customer on a program, I suppose there’s certain critical information upfront that you need. Sometimes that’s hard to get from a customer, right? But obviously volumes and scaling, some of those early inputs are very important for you to do that DFA, right?
Travis Garrison
Yeah, so defining the URS, the user requirement specification, is key in the beginning of that. It’s not only what do they want, but it starts formulating how are we going to answer this, right?
And a couple later slides here kind of go into the DFA a little bit, but really what we’re asking is, how can we make this today, but also can we do it repeatedly? Can we pick it up? Can we move it? Can we manipulate it? Can we inspect it? Or what they’re asking for, CTQs, are even able to be seen. But then we take a step further and go from a supplier coming in, what type of variability are we dealing with? And some of those things always fall through the cracks if we don’t have the forward vision of what the project’s going to be long term.
Steve Maxson
Thank you.
Travis Garrison
Yeah. So DFA, again, these are the core questions on the right-hand side that we ask when we’re going into it. Can the part be picked and oriented reliably? Are the CTQs accessible, and how are we going to use automated inspection cameras, probes, electrical testing to achieve those, especially on molded components? How does the geometry amplify or dampen the variation? And then also, how are the materials arriving? And I have a couple case studies I’m going to go over on how we utilize this information to better help them give us good product, but also keep it consistent as we continue through manufacturing.
And the big thing that I always tell my engineers is the DFA is where we earn automation later. That is key because some things that we’re suggesting and tweaking right now may not answer a lot of questions today, but it does open up the door in the future.
The other side of this is the OEE.
And the OEE in the market is mostly around stabilization, right? We’re looking after we RTM, or release it to manufacturing. How is the machine progressing? Now, going back to my original question, if given a bag of money, how do we make sure we made a smart choice? So the whole MTAP process defines the path. The DFA enables the design. The OEE tells us if the plan is actually working or not.
We take that back to the beginning of the concept phase where we start getting predetermined rates. Okay, I want a 60% OEE at this run rate with this scrap. And everyone wants 0% scrap, but in reality we have to have some sort of threshold. So we start putting it into the model, and as we start getting into our capital investment request and some of the development, now we can utilize this information because we have a good baseline. Where are we today and where do we want to go? So when we start talking with finance and the executive team, we have a clear picture of where we want to be now and where we want to go later, but also the cost around it. And what does that ROI look like?
We get to RTM, stabilization, and stabilization is something I started putting in this last year. There is always this stigma between engineering and production that engineering tosses over a machine that’s not perfect. And the reality is there’s always one or two things that need to be adjusted, tweaked, fixed on an automated machine as it enters production. But really the struggle was, what tools are in place to really start root-causing and drilling down to what those issues were? And that’s what the stabilization period is. But it also feeds back to the CER to say, yes, we are meeting what we said we’re going to meet. Yes, it is doing what we said, and we are being profitable. So it kind of answers a lot of questions where there used to be a lot of friction.
And then the post-stabilization is just tracking the OEE, looking at the continuous improvement opportunities. But the important thing, as we talk about going from manual to a lights-out scenario, is we’ve got to make sure we have a consistent and repeatable process, and we also know the failure modes. So then when we do go to lights out, we know how to either auto-recover, how to navigate around them so a machine doesn’t just sit idle all night.
11:20 From Manual Assembly to Lights-Out Production
Travis Garrison
So one of the case studies is we had this customer come in and they had a really nice growth profile, a complex medical device that was stuck to the body. But when we were first brought the project, we started this MTAP process, we started determining, okay, right now the volumes don’t make sense to do full automation, but we’re going to have to do some manual assembly, but this is where we want to go.
So we drafted out this whole process from manual to semi to fully automated to what I call the Cadillac, to lights out. So when the customer first came in, we decided, hey, we need to be able to put this molded component within this cutout on the sticky foam, and manually it is extremely hard to do because once it sticks, it is stuck. Pretty much we’re good.
So we developed a very rudimentary manual station to simulate this operation. While doing this, we decided, hey, as we progress through these stations, we’ve got to be able to upgrade them, rev them up, be able to build out our workcell as we develop this technology. So we started coming up with a plug-and-play architecture. So as I put a station on, it doesn’t matter if it’s one or two, I don’t have to do additional programming and we can just go straight into releasing onto the machines.
And part of that was the ability to validate offline too, because in the medical industry you’re always very constrained with validation requirements and so forth. So we developed this technology following an MTAP program, and it kind of just started growing legs, right?
But as we progressed, we developed this base station and went on to a semi-automated platform, which we called the Damos, and then it went to this automated version as we started putting foam, molded foam, top placement, and other operations for inspection onto the system.
Steve Maxson
That’s a pretty impressive reduction in labor, even the semi-automated going to full automated too. It’s compelling.
Travis Garrison
Yep. And the biggest thing I can say is it’s not always chasing the labor mark, right? There are times where we have to start doing more complex quality checks and also just to make sure that we can be repeatable in assembling the devices. So that’s really what started driving this evolution of the automation.
Steve Maxson
Okay. You do take up a little bit more floor space though, right?
Travis Garrison
Yeah, it does start taking up some floor space, and that was a concern with developing it.
The next slide here shows our current state. So this system right here on the left-hand side is currently what the machine is. There’s a MagneMotion rail that runs through the center that moves the components around to each station. Each station does the operation. So pretty much it’s already hands-off. The operator doesn’t have to do much intervention other than error recovery. But right now we are in the process of moving to our lights-out solution, which you see on the right-hand side. That’s all conceptualized right now. This will take the product from raw material all the way through packaging.
To get here, there was one curveball in the project that wasn’t caught necessarily earlier, but it did start showing up later as we were developing the stations, which on the next slide is the wire. So when we go to the DFA, it’s not always what’s the heavy lifter, what’s the big screaming item. Little changes like this where we go from a fanned-out wire to a disc not only enable the ability to do automation or robotic pick-and-place, but it also reduces the risk a lot, even in a manual setting.
So the original display design, we had to put seven to 10 assemblers on the line just to place this wire down. There was high risk on the repeatability, but also the customer, based on the fan design, required certain retention so the surgeon couldn’t pull on this wire and pull the wire out of the device, right?
So the new design, we actually incorporated some features to encapsulate it more, to clean up the signal. But the big reason was now we can actually do the pick-and-place, which at the bottom of this slide here is the station to bridge between what we’re doing today and this fully automated system.
And just to kind of close up on the three tools that we’re using, the OEE for the machine, this is what the operations team and engineering team gets off the machine, and it really starts painting the picture on how well we are actually keeping up production, how mature the process is, but also answering a lot of those questions as I’m releasing these automation projects of, are we actually meeting what we promised to do? And this is definitive proof that we are actually able to produce what we said we’re going to be able to produce.
Steve Maxson
Travis, this concept of the OEE, you talked about a URS upfront, sometimes from the customer. In my experience in extrusion, selling extrusion lines, when somebody would give me an OEE requirement upfront to quote an extrusion line, it was like, hold on, time out. I can give you equipment and a good process that’ll be stable, but this has taken it too far. Now that’s me selling a turnkey extrusion system, a little bit different, but still, this is exactly my point from earlier. This is something you need upfront, right?
Travis Garrison
Yep. Okay. And we do put this into some models. So as I’m getting information in from the customer at the beginning, I can start taking their throughputs, their scrap, and also some of the process steps and start generating a simulation of what we want to try to achieve. Because at the beginning it’s really important that everyone’s on the same page. Everyone has the same idea. So when we get to the finish line, there’s not, well, why doesn’t it do this? Or we should have added this. No. Spend more time upfront during the concept to really define what the end is and everyone’s going to be happy.
Absolutely.
Okay. And on the next slide here is just a little bit more of what they get back. But going to a lights-out scenario on the right-hand side is critical. I’m listing out the biggest error to the one that’s not very much. But now we can actually sit here and focus on, hey, the top five here, we’ve got to be able to answer before we can even approach lights out, or the machine is going to be sitting idle all night.
And this is somewhere that I’ve seen a lot of times where people jump into a lights-out scenario way too soon because they don’t understand the true nature of the machine and exactly what their issues are leading into errors and how to reduce those. So if you don’t have a good vision of that whole landscape, jumping in too soon, you’re applying so much risk to your design that it’s going to be a very steep uphill battle to get it across the finish line.
So having this information just solidifies this is how the machine is today. We are in a mature state and we’re ready to even have this talk to progress.
20:46 CTQs, Inspection, and Process Monitoring
Steve Maxson
Okay. Interesting.
Travis Garrison
Yeah. Now, going a little bit deeper here, with our DFA and everything, we’re looking at the CTQs, the critical-to-quality attributes. What does the customer deem super important for this device to work out of the gates today?
One thing that, the biggest takeaway I can give you right here, is doing inspections is more than just a pass-fail result. We’re already doing the tools, we’re already pulling that data. But if you utilize that data, we can help out our suppliers and also our process engineers quite a bit with answering some issues.
On the right-hand side here was a surgical device. This was the molded component that 5 millimeter staples went into, but we were having issues with some of the pockets caving in on themselves, some of the flashing coming through, not making the staples able to sit correctly into the part.
So we were able to actually give back data on the widths of each cavity, identification of cavity one is within tolerance, cavity two is showing a trend to start going outside of tolerance. So then they can take that information back, start retooling earlier before we just have a huge fallout of incoming material.
But the other big side of this, in being able to trend the data off those CTQs, is being able to create clear signals to reduce any firefighting and friction. We’re not guessing. This is where we’re trending. These are the cavities that we’re actually seeing. But it also enables the technicians and engineers to more precisely focus on certain root causes instead of just looking at this huge landscape and trying to figure out exactly where do I start.
Steve Maxson
You talked about trends right there, detecting any directional drift from the process you’re talking about, right? And so that you could identify that early on and do some kind of feedback with the equipment or the process?
Travis Garrison
Correct.
Okay. And then it could be something as small as a cavity staying consistent based on a width, or it could be more of a failure mode analysis that I’m starting to see flashing bleed through. I’m seeing a cavity not fully formed. There’s something stuck in there where it’s not a full through-hole.
So we can show those failure modes and bring it back to the supplier or to the manufacturing group.
Steve Maxson
Gotcha. Thank you.
Travis Garrison
And this is just another example, same idea, but with these molded foam tops. We were having some issues where foam molding, I always say it’s more of an art than a science, but our supplier will disagree with me.
Sometimes the cavities would be more marshmallowy, so they would extrude up more. Now I can actually feed that back. What is that height? But also, am I ripping the liner? Because it was supposed to be a kiss cut. Is it not a through-cut of this matrix? And I can really start relaying that back. Then at least their tooling, with our supplier here, they can fix each one of these individual cavities in their molding process. So I can just tell them, hey, cavity 23 is starting to show an 11% increase in failure because of X, Y, and Z, and they can retool it sooner so we can keep getting good product coming in the door.
And with the vision and trending the CTQs, when we start getting down to the micro level, it is extremely important to be able to see this information because a lot of times it’s either so small or something looks so insignificant that you don’t think it’s a big deal. But in reality it’s a huge issue as we go into micro molding.
24:59 Micro Molding Challenges and Precision Manufacturing
Steve Maxson
I would think a huge issue just to be able to measure it.
Travis Garrison
Yeah.
Vijay Kudchadkar
Yeah, that’s measure them.
Travis Garrison
Oh, go ahead.
Vijay Kudchadkar
Absolutely. Medical device manufacturers are constantly innovating to help save lives or make our lives better. And in this quest, they’re developing parts that are getting more and more difficult to manufacture, assemblies that are getting more and more difficult to manufacture.
I truly believe that it is our duty as tooling experts, as molding experts, as automation experts, to push the boundaries of manufacturing to help them achieve their goals. Now, many of their devices are getting smaller and smaller and more complex so that they have the function, different functionality, to go into different parts of the body.
As a result, the parts, as I said before, are getting more and more complex. The part in the top left corner, the weight of that part is 0.00004 grams. That’s the weight of an eyelash. Wow.
The part just below it, you can imagine, just going back to that part, trying to build the core cavity, then molding it. After you mold it, managing it so when it comes out of the mold, grabbing it, transporting it to the assembly line where it needs to go without losing that part. The complexity comes from simply the size of the part.
Then also being able to measure something that small. The part below it is a relatively bigger part. It’s about half an inch long. The complexity there is, it’s out of PEEK and it has 3 micron sharps on it. Trying to mold a part with sharps in PEEK, and you can see those sharps are going in different directions, so being able to build tooling for that was a huge challenge. This tool has 14 moving cams that have to get out of the way just for that part to get out of the mold, and then you have to be able to handle that part so that you don’t damage those 3 micron sharps.
The part below it is a bioresorbable part. With bioresorbable, you have to be very careful with how you handle them. You don’t want to degrade the material. You don’t want the intrinsic viscosity to drop below a certain value. So they’re very sensitive to temperature and pressure. But then in these applications, the parts are getting thinner and longer, which increases the aspect ratio, making them harder to fill and harder to mold.
The part below it has 3 micron sharps again, but these sharps are curved, which creates a trap steel condition, so you have to build tooling that has to get out of the way to clear those undercuts.
There’s a part there that has microfluidic channels that start at 250 microns going all the way down to 3 microns. To create a microfluidic channel that’s 3 microns wide and deep, you have to create steel that is 3 microns wide and deep and high. That’s not easy to do in pre-hardened steel, just machining it.
The bigger challenge is that if you do manage to machine it, you do not destroy that steel when you try to mold the part because you’re injecting at very high temperatures and pressures. Even if you just wipe your finger on that mold, it’s possible to get rid of that steel. So the challenge there is being able to mold it without damaging the steel.
So parts, as you can see here, are getting more and more complex. Many of these parts, in fact most of the parts, are not standalone. They don’t have a standalone application. They go inside some kind of subassembly or assembly. And because the devices are getting smaller, more complex, and we need more functionality in the device, the tolerances are getting tighter and tighter.
In the past, in injection molding, you never wanted your tolerances less than plus or minus 50 microns. Now it is not uncommon for us to see part tolerances that are 25 microns or lower. Twenty-five microns is one thou. So it’s not uncommon for us to see part tolerances that are less than one thou.
Now when you get into tolerances that are this tight with parts that are complex, you have to double down on what you know about injection molding and control all the factors that affect the dimensions of the parts. We have a proprietary PFME process that we go through to ensure that we have control over all the factors that affect the dimensions of a molded part.
When you’re trying to achieve tolerances of plus or minus 8 microns, let’s say, on the molded part, your tooling needs to be submicron precision. Most tooling in the world that is built is built to a tolerance of plus or minus 5 microns. If you try to use that tooling and make a molded part with plus or minus 8 microns, you have no chance.
So the tooling, which is one of the most important factors, has to be less than plus or minus 1 micron. Now I’m showing these tolerances here. If you could just click, I’m going to show you the CPKs achieved on those parts. The target CPK is 1.33. When you follow this process and use submicron precision tooling, you can see the CPKs that are possible with these extremely tight tolerances.
Please don’t take this as a license to go tightening your tolerances, but this is mainly to show you that if it’s truly required for a lifesaving, life-changing device or technology, it is possible to achieve high CPKs on tight tolerances.
36:22 Injection Molding Automation Strategies
Vijay Kudchadkar
So going back to automation for injection molding, there are many levels of automation that can be used in injection molding, starting with simply auto-degating. So whenever a part is molded, the polymer has to enter the cavity through the gate. And in many applications, whether you’re using a tab gate or a fan gate, the whole cold runner gets ejected with the part, requiring secondary operations.
So one of the things that we can do early on when we’re designing a part is really think about where are we going to gate the part? How is this going to be gated? And during your DFM or DFA, if you’re able to allow for a tunnel gate or a valve gate or a thermal gate, then you have removed all those secondary operations that are required normally during degating.
Then when the part is molded, you have an option. You can open and close the mold, and every time it opens, the parts can free-fall, right? Or you can use a robot with end-of-arm tooling to grab that part out of the mold and place it either onto a conveyor belt, or you might have packaging built in so you place the part directly into packaging, taking manual steps out of it.
Now there’s other levels of automation which really help reduce the amount of secondary steps that are normally involved, starting with insert molding or overmolding. Many of the micro parts are usually molded and then taken away, and then you try to either laser weld or glue them together. But if you’re able to insert mold or overmold or use two-shot molding or multi-shot molding, you eliminate all those unnecessary steps that you have when you did not design the part for insert molding or two-shot molding, or if you did not have the ability to two-shot mold or insert mold extremely fragile geometries.
Another level of automation is trying to assemble the parts between the plates. With in-mold assembly, it’s possible to mold parts, spin the tools around, and when the molds come together, you assemble in the mold, or you have end-of-arm robots and end-of-arm tooling that grab the parts and assemble them during the cycle.
And one good strategy, as much as possible, is to try to do as much as you can while the parts are still inside the mold. Because when the mold opens, before you eject the parts, they are perfectly fixtured and there’s a lot you can do while the parts are still in the mold.
Now what’s important is to be aware of all these options and processes when you’re designing the part. If you’re aware of these options, then you could design your part and subassembly so that you can use insert molding, two-shot molding, or even in-mold assembly.
Next level of automation, you could try to get rid of secondary operations by doing things like in-mold labeling, where you can get rid of a lot of decoration steps later on by placing the label in the mold and molding the label into the part. You can also use cube or spin-stack tools where the mold opens and then it rotates to different positions while the mold closes again. You can have secondary operations at the different phases.
After that, when it comes to automation with injection molding, you could try to design your assembly so that you can do press-side assembly. So you have two molding machines running in parallel. The parts get ejected through end-of-arm tooling, they come together, and you’ve built press-side assembly operations.
And then the last form of automation is what Travis described earlier, where you build automation equipment. Parts are molded, transported to that assembly automation cell, and then they get assembled together with multiple operations.
Now one thing I want to say here is, when you design automation equipment, please make sure that the tooling for your automation equipment doesn’t require tighter tolerances than the molded part. I’ve seen this too many times where you could make a part to print, but then it doesn’t go through the automation equipment because the automation equipment was built to an even tighter spec. It becomes a nightmare for supplier engineers. They’re stuck in the middle. The molding supplier made the parts to spec, but now they’re getting yelled at because it’s not going through the automation line.
Yeah, that’s the importance of the DFA for sure. To bridge that issue.
Steve Maxson
Yeah. This is interesting, Vijay, about the in-mold processes that can reduce secondary operations. Right? I know you talked a little bit about some secondary, but in-mold assembly, the labeling’s pretty interesting as well. That’s a way to kind of speed things up.
Vijay Kudchadkar
Yeah. If you look at the part on the top right there, you can see you have already three different colors and different graphics because it’s all printed onto the label. So you load that label into the mold, and you mold over it.
It looks nice, but then you can think about how many steps you have eliminated because you did in-mold labeling. Right. And this is something Nissha specializes in, in developing these films for in-mold labeling. And then the molding process is quite tricky because you have to be able to load that film into the mold and then secure it before you inject plastic into the mold.
Steve Maxson
Yeah, tricky is an understatement for dealing with all these, especially the miniature components. Picking and placing them and handling them. That’s amazing.
Vijay Kudchadkar
Thanks. Yeah, so keeping in line with insert molding, it’s extremely difficult. So you can see some of the inserts there. They look big on the screen, but you can see we have grooves of a fingerprint for reference. So being able to handle those inserts, pick them up, place them into the mold, close the mold, and then inject plastic at high pressure around it without damaging those inserts, it’s possible to do with extremely fragile stainless steel needles.
We’ve also done extremely fragile materials like silicon wafers, loading them into the mold and molding around it. You have to be able to maintain that insert orientation.
Now this is where the question comes in. Do we automate or do we do it by hand? Because it’s possible to do insert molding with pickouts. You can place the inserts in the pickouts and then place them into the mold. So when the volumes are relatively low, that’s the preferred method. But then when it’s time to scale up, you have to be able to do this with automation, otherwise you’re not going to be competitive.
Anytime anyone’s designing a part for medical devices, especially in drug delivery, I always say, please imagine, visualize that your device is going to be a massive success. You’re going to need billions of parts. You’re going to have massive automation lines running. So design your part and assembly with that in mind, that one day it’s going to be running with multiple multi-cavitation tools and huge automation lines across the world running those parts.
And if you can design your parts with that in mind, you will save a lot of money and a lot of steps later on.
Vijay Kudchadkar
Two-shot molding is getting very popular. So two-shot molding has been around for a long time, but now two-shot micro molding is getting more and more popular. It’s always been difficult to make one micro part. Now in the same cycle, you’re injecting a micro part and then you’re injecting another layer on top of it, which is quite often smaller than the first shot.
So there you need to have, again, submicron precision tooling. You need to have the injection units that can handle those extremely small shot sizes. What had to be developed was custom precision rotary plates, because there was nothing in the market that was precise enough and compact enough for these applications.
And many of these parts are so critical for the device that normally AQL isn’t enough. So utilizing the developments in automation and vision inspection, it’s quite often important to develop cells where you have 100% vision inspection, measurement of every part that comes out, to reduce the risk when it’s used in its application.
Steve Maxson
Can there be an application where one of the shots or materials is a softer, lower durometer material?
Vijay Kudchadkar
Yes. That is possible.
And that’s one of the applications where you have a hard material and you have a soft material on it. Or it could be simply two hard materials that you normally glue together, and now you’re trying to reduce all those steps.
We had one application where there were two materials and normally there were 17 steps involved in trying to glue them together or join them. And all those steps were eliminated because we two-shotted that.
Steve Maxson
Gotcha.
Vijay Kudchadkar
So it comes out of the press fully assembled. But again, it depends on the application. Hard on soft, hard and hard, we’ve seen both.
I guess back to that, the challenge of handling submicron parts, if you add in a low durometer tacky type material, that makes it even more difficult, I would imagine.
It makes it more difficult. And then adhesion also becomes a challenge because you now have very little surface area. So you have to get creative in your design on how can I maximize the surface area? What materials are more compatible than others? And then pressure plays a big role with adhesion when it comes to two-shot molding. So what pressures can I achieve to get the bond that we need?
But often we’ve seen that by two-shotting it, the bond consistency and strength goes up, which reduces the scrap rates for the customer. They’ve reported to us that their consistency of the strength of the bond is now much better than what they had previously from trying to glue these parts together.
Vijay Kudchadkar
Right now, sometimes it’s not possible to get gluing out of the equation at all. So there are assemblies where gluing is required. So we try to automate that as much as possible.
So what you see on the screen, the entire assembly takes place in that black speck that fits in the groove of your fingerprint. That part is 1 French in size, 0.33 millimeters. That’s a part that’s taken, and itself is a huge challenge, picking something up that small, placing it to within 1.5 micron accuracy, then taking three leads, which are 25 microns in diameter, placing them on that wafer, dispensing nanoliters of epoxy, and then curing it.
This used to be done manually, and as you can imagine, the scrap rates and the cost of the part were through the roof. This is something, because of the labor content, the only way it’s affordable is if it’s done overseas. So the goal here was to develop a fully automated cell with 100% inspection.
So if you go to the next slide, you’ll get a glimpse of the automated cell. So eight stations that are, again, 100% automation. There’s no manual involvement at all, all the way from picking up the wafer to placing it, gluing it, and then packaging it. Eight stations, 100% inspection of each station.
For micro molding assembly, there are many other steps that are utilized. So either we try to automate all those steps as much as possible or try to do as many processes while the part is still within the plates.
Vijay Kudchadkar
One thing we enjoy doing is reducing the cost of automation by getting rid of the need for automation completely. This part that you see on the screen, when the customer came to us, they wanted a microplastic part with filters. They needed a filter inside the part, so whether that was going to be an insert-molded filter, a very fragile filter, or they wanted to laser drill these holes, that could have been built, but that would’ve been expensive.
What we figured is, using the technologies developed in micro molding, we have the ability to make 2 thou core pins. The key there is not just to make those 2 thou core pins, you have to also be able to support it. So utilizing the technology of micro molding, we were able to directly mold this part, completely removing the need for any automation or secondary operations after that.
Similarly, here’s an application where multiple steps were required to make this part. It’s a plastic cannula, and the conventional way to make it is to extrude it. As Steve knows, with experience in extrusion, even a single-lumen tube is not necessarily easy to make, but it’s easier to get a thinner wall section in extrusion than it is in injection molding.
So these tubes are extruded, then cut, flared, tipped on one end, and then there are multiple other steps to manufacture these cannulas. Cannulas are widely used in drug delivery and monitoring devices. They’re the only part of the device that actually goes below the skin, so it’s very important for them to be biocompatible as well as comfortable for the patients. That’s why you cannot increase the thickness of the wall too much.
Now trying to make hundreds of millions of these parts with this six- or seven-step process can be expensive. But nobody could mold these parts because of the extreme thin wall section, as well as the thin annular section, the core pin that’s required to make the annular section.
But now again, using the technology that was developed for micro molding—
Vijay Kudchadkar
We developed the ability to directly injection mold this part, achieving that 4 thou wall section as well as the 8 thou ID, 200 micron diameter core pin. The key to being successful on a part like this is being able to support that core pin. If you don’t support that core pin, it is going to break under the high pressure. So supporting the core pin was very important.
And now that it’s possible to injection mold these parts in high cavitation, you get rid of all those steps and you save a tremendous amount of money. You significantly reduce the cost of automation.
So that brings me to the end of my presentation. Happy to answer any questions.
47:52 Post-Molding Automation with MMT
Steve Maxson
Thanks, Vijay. Thanks, Travis.
We talked about automation as a lifecycle from early design decisions through stabilization and OEE, but automation doesn’t stop at the press. Post-processing, inspection, and assembly is where repeatability is either protected or lost. And that’s where an automation integration partner like MMT comes into play.
So let’s extend this conversation with Crew Feighery from MMT.
Steve Maxson
Hey Crew, thanks for joining the webinar.
Crew Feighery
Hey Steve, thanks for having me. Appreciate it.
Steve Maxson
Yeah, we just had a great conversation with Travis and Vijay about lights-out molding, and I thought it’d be appropriate to have you on to talk about some of the things that MMT does through their SOX division, automation division, in automating. And I know that you have some technology platforms, a wide range, right, portfolio, catheters and everything, but you also do some work in automating the attachment of a rigid proximal hub to a catheter shaft. So I wanted to talk to you a little bit about that.
Crew Feighery
Sure. Happy to do so.
When you’re thinking about bonding hubs onto a catheter shaft, obviously there’s all the important criteria with the design and manufacture of the mold itself for the hub and the features within. And then the things to think about there are, with the catheter going into that hub, you’re typically going to bond it in one of two ways. It’s either going to be with a solvent bond or a UV-curable adhesive. So those would be the most traditional.
With that, traditionally what you have is an operator who’s going to be applying the adhesive or the solvent. They’re going to be putting these pieces together in a manual process. But the challenge that you can face with these manual processes is you don’t have a really good way to understand exactly the amount of adhesive that you’ve dispensed, to make sure that was properly distributed on the part before you put it in. So you get that operator variability.
So the benefit of what our ICS division has done is they’ve automated that whole process. So picking and placing the hubs, applying a very specific measured amount of adhesive or solvent, pushing the parts together with an associated force, and then also doing the inspection of the part after it’s been bonded, whether it’s using vision or a mechanical pull-type test.
The thing to think about with a UV-cure adhesive, obviously that UV light has to get in there, so those would be more of the clear hubs that give you that capability. But for the ones that are more opaque, you have to use more of that solvent-type bond.
And again, because you can’t see in, you can’t see what’s happening inside of it, having that very reliable, repeatable automated process is key. And again, the benefit with automation is it’s done the same way every time when you’re putting the parts together.
But the other thing you want to think about is, you do have an operator who’s a great piece of automation, right? They have great dexterity in the hands. They can put the parts together, they can feel the forces, and more importantly, they can visually see what it is they’re working on.
So the thing that’s often overlooked when you look at automating a process is you have to account for that inspection, that in-process inspection during the sequence. Because if you don’t, what you can end up with is a whole bunch of parts that come out the other end, and your yields just look terrible because you had some sort of anomaly happen in the process.
So being able to visually inspect or mechanically inspect, or do it in a series of different ways, is super critical to automating a process and having a very robust and repeatable process out the other side.
Steve Maxson
Absolutely. Great point. That example you just shared, I assume it’s attaching a rigid hub, polycarbonate, ABS, whatever it might be. In MedTech we love soft materials too, right? Compliant materials because they’re compliant. But that can create a challenge in the manufacturing process, especially post-extrusion or molding, because of the handling. One is, it’s tacky, right? So there’s ways that you can kind of reduce the tack, but also the compliance that we want for the application makes it a little bit difficult from a manufacturing or automation standpoint, right?
Crew Feighery
Yeah, absolutely. When you get into the softer end of the spectrum, things get more challenging. So just like on the catheter side, same thing for these types of molded devices, whether it’s like a duckbill valve or a small silicone ocular cleaner that needs to have tiny holes in the end and needs to have the flash removed.
And flash is a key piece. Lower durometer, these thinner parts, you get flash from the parting lines, you get flash off the end of the tip. So that’s where we’ve been able to leverage some of our cutting and trimming technology that we’ve developed over the years to help remove some of that.
But things that you have to think about when you’re punching a hole or you’re doing cutting are, this soft material is a compliant material. As you cut it, it wants to move and deflect and deform. And if it deflects as you’re cutting it, you’re not going to have a clean cut. You’re not going to get that square or whatever type of dimension you need.
So the type of material you use as a backstop material or a sacrificial mandrel, or something that you’re punching against or cutting against, is really key in the process.
So if you think about these types of parts, like a duckbill valve, for example, it’s going to look like a bit of a pyramid. You need to put a slit right down the top of that. But even something as simple as where you put the slit in the part, where it’s positioned, how large that dimension is when you go to punch through it, is key to the performance of that product when it’s done.
So once you make that slit and you remove the blade, the valve closes back up as it’s supposed to, and it’s nearly impossible to inspect that. So doing things like a go/no-go automated inspection, to make sure that hole is large enough or the opening is large enough, but also once you have it open, now the part can be backlit and you can actually measure the part and use vision inspection to see that feature.
Similarly, if you need to punch a hole in a part, once that punch in the part has been made, you’ve removed the plug of material, you can inspect the dimension of that hole to make sure your flow rate is going to be correct, because that’s typically what it’s for. But also make sure you have a very clean cut, because these things are all going to be called out on the drawings.
So you want to make sure when you make these features into the part that you’re not just making them, but you’re also verifying that they’re correct. And so adding that vision inspection downstream of the automation is a key part of the process.
Steve Maxson
Absolutely. Excellent. Thanks for the insights, Crew.
Crew Feighery
Yeah. Thanks for having me, Steve. Appreciate it. And thanks for being a part of it.
54:36 Upcoming Events and Thank You
Steve Maxson
All right.
Before we close out, a quick look at what’s next from Chamfr. Head over to our new Resources Hub, your go-to place for practical R&D tips, new technologies, and sourcing trends to accelerate R&D, including MPP conferences, webinars, podcasts, technical articles, and more. Scan the QR code to check it out.
Also, we have a full slate of MPP conferences this year, starting with MPP West in April in Mountain View, California, MPP East in June in the Boston area, MPP Ireland in September in Galway, the day before MTI, and MPP Minnesota, back at our favorite golf course, Rush Creek Golf Club in Maple Grove, Minnesota.
We host webinars each month, and coming up next month, I’m really excited for my colleague Katie Karmelek. She’ll be co-hosting with Chang Wei of dsm-firmenich. They’ll be talking about the next generation of PFAS-free inner liner technology.
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Huge thank you to Travis and Vijay of Nissha Medical Technologies and Crew Feighery from MMT. Thank you, everyone.