Craig: Exactly and that’s I’ll just kinda get [00:02:00] uh, we’re very sensitive about sharing IP.
So, I can’t share any details the end product or anything, but we’ve actually done some needle molding at AccuMold where we’re molding needles with sharp points and I can just describe to you some of the splits that we do to where we can put split lines and specific areas on those parts and we can mold needles to sharp points we can do lots of different venting strategies.
So we’ll Do some custom vent channels very small lands. We’ll do like feather style venting to where we’re actually just modifying surface textures on our mold steel to strategically vent out of some of those very thin areas, very sharp micro sized features on our parts. So lots of different options we can do from the mold build and mold design side to accommodate a lot of those extremely small features.
Jeff: Yeah, I think that’s key is we definitely have the capability to put those features in the mold, but to get them to show up on the part requires a lot of what you’re talking about.
Craig is how do you get the [00:03:00] process and how do you control the process to get those features in there? Every shot, over millions of shots.
Craig: Yep, exactly. And we do a very thorough DOE process to establish the ideal processing windows on the molding side of things, as Jeff. And. There’s a lot more than just like venting and split lines that go into being able to do that in the mold builds too. It’s a lot of very strategic heating and cooling of mold features.
As you guys all know, I’m sure when it comes to molding, you need the plastic to be molten and flowing very well to be able to fill in at least thin walls and small features. And we have some very strategic ways to do that at Accumold where we’ve done some extreme materials for small mold cores, things like that, to superheat them and then super cool them very quickly within cycle.
Be able to fill the thin walls out and then also be able to, eject parts off some of these mold details and run the molds very quickly as well. So lots of different studies we’ve done to figure out what’s optimal and do that effectively.
Jeff: Yeah. And I, [00:04:00] Coming from the development side, I utilize our mold designers and mold team a lot and then represent the customer at AccuMold often and I’m able to show them, here’s the tolerances we’re able to hold and the feature sizes we’re able to hold and we’ll measure those parts, which provide the reports and the results are great. Amazing to me, you’re not having that tool making background like you do, Craig, to see those parts so pristine and be able to show the customer, Hey we’re in this range. So when we go to test the parts, we can do a lot of the testing at Accumold or send them to the customer and have the customer test them.
We know on that batch of parts or even across the batches. This is what you’re actually testing, and we know if you need to change something, we can change that extremely accurately and get exactly what you expect out of that part, [00:05:00] or if the change is to strengthen a rib or strengthen a feature you can be assured that we’re going to hit that dimension and those dimensions and make that perfect.
That part to print and it avoids the, are you troubleshooting the design? Are you troubleshooting the manufacturing process? You as product designers and developers, you want to be troubleshooting your design. You don’t want to have to worry about how the parts are coming to you. The parts should be coming to you as you design them.
Craig: I guess I didn’t really answer what our kind of most common question is, how thin we can go with a lot of these materials and, it’s it’s obviously very feature dependent and part design dependent, but. We get questions all the time as, Craig, I would really like to mold this part with peak, but I know that’s not possible.
And that’s where our upfront team usually can look at that component and reference some of the thousands of successful projects we’ve done and say, Hey, you know what? We actually can do that part with peak, it’s a 15 to one aspect ratio. We’ve done [00:06:00] this project and this project successfully with aspect ratios greater than that.
And We can do that. So…
Justin: That is the simplest question and it’s not a simple one, but I think maybe we should tackle that, which is how thin like that. Everybody wants to know how thin can you go and there are multiple answers to answering that with a lot of clarity.
Craig: There sure is. And it’s there’s a lot of experimentation that goes into really figuring out what the borderline is with that. And And anybody that really pays attention to Accumold’s advertisements, things like that knows that we mold a thin wall cannula component. We’ve put a lot of work into that at Accumold and we can share it.
We try to share that because it really shows some thin wall molding that we do. So if you’re unfamiliar, it’s a four thousandths thick wall that’s about three eighths of an inch long. So about a 90 to one aspect ratio. We’ve molded that with a couple dozen materials now lots of different variations of polypropylenes, polycarbonates FEPs, Teflons, [00:07:00] PBACs, good variety of different materials and we use information we get from doing parts like that, doing thin wall studies to figure out how far we can go.
So 90 to 1 and greater is very common with a lot of materials you get to some of the lower flow materials like peaks, all temps, things like that, it’s reduced from there, but. Very feature dependent,
Jeff: yeah, and one thing I found interesting about that project too is the concentricity of the outer diameter to the inner diameter is spot on a lot of those. I mean we’re like a half thousandths was is a huge amount when you’re talking to four thousandths wall or in trying to get that to hold that tight.
Craig: Yeah. Yeah. You’re very correct there and stuff we get a lot from our customers is, Hey, I know you can do that 90 to one aspect ratio, but that four thousands wall is way too thick for us.
Can you do one thousands? And a lot of projects like that, we’re actually more than happy to take [00:08:00] on, that everybody else out there in the molding world would probably laugh at ya, but we’ll take those on as a prototype, and we do a lot of, best effort studies to where we can start out with, the optimal scenario, knowing that, that 1, 000th wall is very unlikely to work well, and we work with a lot of our customers to do steel safe changes on their prototype molds to, Really dial in what’s possible and really optimize part designs.
Jeff: Yeah. Yeah. Craig, can you talk about like gates. Gates are a necessary feature on parts, but often not desirable. What are some things that. that you’ve seen that help hide those or keep those inconspicuous for the customers?
Craig: lots of different design strategies you can look at there. It’s not every gate needs to be directly into the side of a part in a parting line gate.
So we’ll see, gate recesses designed in a lot of people design in features to where we can drop gates into kind of the faces of [00:09:00] parts using either direct valve gating or three plate style molding. Get those gates in areas to where they’re not going to be on a cosmetic surface that’s visible on the end product.
We see a lot of different scenarios like that and have a lot of different work around. We love when customers bring that up and we can look at a design and kind of spin it around with them and figure out what’s going to be optimal.
Jeff: Yeah, and I think of wearables and such that cosmetic surface is usually large and flat And maybe contoured, but definitely no features on it.
So a lot of times you’re forced to put the gate on the other side where there are features and how do you get around working around those features when you’ve got a gate that you need to put in there?
Craig: Yep. A lot of that is gonna be totally part and mold design dependent, which is why we like to work up front with our customers and figure out how we’re gonna do that.
We look at the parts early on and determine where the best location for the gate’s gonna be. And we can design around that to be able to get gates in there to very [00:10:00] difficult areas where a lot of other suppliers don’t want to get into when it comes to reaching in with a small gate funnel.
So.
Jeff: And a lot of times that when that part comes out of the mold it’s finished, there’s no need to de gate it. And there’s no worry about debris or extra handling steps. It’s, it can be robotically picked and put in a package and not touched.
Craig: Exactly. And that’s key to really the high volume projects is not having any secondary operations to remove gates, so we’ll do either self shearing gates or use automation to shear the gates as they come out of the mold, but yeah, lots of different options there.
And gosh, something I would like to get into since we have you on here, Jeff and Jeff is really great. He works a lot with our light assembly team and the new product development at AccuMold. And, what are some of the most. Common techniques to be able to really shrink wearable devices down?
You’ve seen a lot of designers with our customers combining components or, thinking about ways to [00:11:00] integrate seals over mold stuff. You just
Jeff: Yeah, you just hit on a couple of them there, Craig.
Is how do you combine multiple features or multiple existing components into a single component? And you’ve already hit on the ability of the micro mold platform to create features that are scattered all over that part, not just up there by the gate and get crisp ones, but we can get nice features far away.
That, that’s a big thing, but with sealing of wearables is whether it’s water resistant or waterproof or has a really stringent moisture ingress requirement on it. That’s where we get into sealing and possibly using even like a, instead of purchasing an insulation. An additional seal, an external component as a seal, is we can overmold that seal right onto the component.
It’s a two step process, [00:12:00] but the nice thing about it is that overmold seal is exactly where the customer wants it. It’s filled out. We can put any type of sealing features on it, whether it’s multiple ribs or a round rib or thicker in this area and thinner in this area. Different ways to get that seal just and the nice thing about when we ship the part is that seals integrated into the one component.
So the customer’s assembly assembly lines, they’re purchasing, they handle one, one component and one component only, and everything’s integrated into it. And the amount of features for overmolding out there are enormous, just durometers permeability. It keeps coming up again and again, especially with wearables is how can we keep the moisture out of our electronic components that are inside this device?
A lot of that’s published, but we’re also at Accumold will, as Craig mentioned, do a lot of [00:13:00] prototyping and provide. Easy, easily prototype components to get to the customer for their testing. We do a lot of testing in house. The benefit of that is, is we can iterate extremely quickly identify problems, go to their design group.
They can recommend here’s what we need to do. And then we can go to the customer, not only with. Hey, there was a problem in this area, but here’s how we propose to fix it and Here’s when it can be implemented and do that iteration without having to send parts wait for lab results wait for a lot of Iterations on the product design we can get through that really quickly and get that device or that component to market So much quicker that way.
Justin: So as you guys keep tackling more questions, I just want to remind everybody listening today that at any time you can put your hand up or you can, there, there’s little icons in the bottom of your screen. If you’re on mobile, I’m not sure the experience on desktop, but you can put your hand up or [00:14:00] request to speak and that’ll allow us to bring you on stage where you can ask questions directly to Jeff and Craig, who are both in the studio.
As a reminder, for those that have just joined. We’re running everything through Craig’s channel. LinkedIn doesn’t allow us to split the channels in the way we’d like. So we’re all in the studio together and to get the best audio quality for you. We’re all going through Craig’s account. So Jeff is here.
Craig is here. I’m Justin in the Accumold communications team. And we do encourage all of you to put your hand up and request to speak. That way everybody else can learn from your expertise as well. Because if there’s one thing I think that Craig and Jeff will agree on, it’s that not only are you guys experts, but we work with experts.
In the field, like the engineers that you work with on a daily basis are the top engineers in the world. So I’ll let you get back to it. But if anybody wants to participate, we ask that you do and put your hand up at any time.
Craig: appreciate that, Justin, and you’re very correct. All of the engineers we work with that are different customers are. extremely skilled at what they do. [00:15:00] And to couple on what Jeff was talking about there, it made me think of another very common thing that we see here at Accumold, very common theme of the last, probably year or two is over molding electronics and keeping liquids out of those.
That’s something we’re very familiar with at Accumold, whether it’s small sensor wires, PCBAs things like that. Do you have any kind of strategies, Jeff, that you’ve seen that work well? Any materials that work well to overmold some of those very delicate electronics that we’re seeing in a lot of wearable devices?
Jeff: Yeah great question, Craig. And I think when we, as we’ve continued to get involved with that, we’re often looked at low pressure molding, our parts coming from the low pressure molding world, and, The question is asked can we use thermoplastics to overmold and still get some of the same Results or even improve stiffness and improve permeability With thermoplastics that we couldn’t get from low pressure molding and then on [00:16:00] the cost standpoint Thermoplastics the process to do that is so much faster As well, so the piece part price should be less as a result of that.
But yeah, they’re PCBAs and the components on them, whether it be like oscillators or standard resistors, capacitors, and even batteries really all have to be taken into account and strategies are goes back to the gating strategy for filling out features and where flash is at a lot of times. You want to keep that flow front as cool as possible and as low pressure as possible when it does reach those components.
So how we adjust the gate or gates to overmold like a PCBA or any type of electronic component is so critical. The interesting thing is with low pressure molding, those, the melt temps of those are very similar to say like a [00:17:00] polypropylene. So temperature isn’t necessarily the difference there.
But pressure is so on low pressure molding, you’re often looking at say 50 to 200 PSI with easy flowing thermal plastic, such as polypropylene, depending on the features. We could be, say, 100 to 1, 000 PSI, and that’s where Accumold can come in and help design those features so it doesn’t take so much pressure to fill out those features and cause damage to the PCB or whatever insert.
is in there. If those pressures need to be high, then there’s a lot of strategies on how to support those features. Not only from the pressure when the, Pressure builds inside the mold, but also that if you consider that flow front coming across the plastic flowing across all these components on a board, just a, I [00:18:00] envision it like a sandstorm coming over a city, it’s just barreling over the top of it and how you treat those components and keep them keep them safe from that flow front.
But the beauty of overmolding with thermal plastics is, especially plastics like polypropylene that are easily to flow, they’re super with moisture barrier, is that Once it’s over molded, you’re done, and there’s no need for another shot. Say if you’re using a softer material, like an LPM, a lot of times you’ll do a second shot over the top of it to stiffen it up to make it handable or able to be used by users in a rugged environment.
If we can do it in one shot, that, that’s ideal and thermoplastics can enable that.
Craig: That’s great, Jeff. Yeah. Appreciate all that insight and that’s all fantastic. And makes me think, what are the some of the most difficult substrates you’ve had to deal [00:19:00] with in regard to overmolding, not just electronics, maybe a small needle with a sharp point or a wire or a tube, or do you have anything in mind?
Jeff: Yeah, we’ve, The first one that comes to mind is a gold plated, anything, nothing sticks to gold. So that’s and not thermal plastics not adhesives. It’s really hard to seal against that. So that has to be a consideration if we have an exposed gold surface in the electronics or in the inside on getting that to seal is pretty difficult.
Probably going to require another operation, and that’s where the the elastomers come in. The elastomers can provide that seal around, around the goal to keep liquids or moistures from coming in. And then this, then the sensitive materials we had a customer with a few Really sensitive components where we had to shift our gates around to keep them from getting damaged, but we’ve always found supporting those components and locking them into the mold to support them [00:20:00] is absolutely critical.
And that’s that enables the overmolding of some pretty fine components. We have overmolded tiny wires that are, 200 microns in diameter. Not so hard overmolding, but getting them into the mold and holding them in place while the plastic is injected around them. That’s the trick.
And then we, Would measure position repeatability, retention force, how can that replace say a manual insertion or a post molding insertion process where glues or adhesives or some other method to hold that, hold those components in places are needed. If you overmold it, a lot of times the plastic will lock on it and And as
Justin: And as a reminder for those messaging questions, I think you did get one Craig? We won’t be using your name. We’re just going to assume if you’re messaging a question, [00:21:00] you don’t want your name being attached to the question you ask. So again, Craig is receiving messages right now. I think you do have one to go over. Unless you want your name said, we will assume that you don’t want your project being discussed and you don’t want your name being said.
Go ahead, Craig.
Craig: Yeah, definitely. So I’ll I’ll jump back into that conversation there, Jeff, in a second here. But question we had, how thin slash small can you go and what kind of material lends itself to the smaller features versus larger parts? So very common questions typically when we’re talking wall thickness, we’ve molded it.
Wall thickness is down to just two thousandths of an inch. Like I said, we’ve molded sharp points on things as well, so we can go extremely thin, extremely small. Materials, polycarbonates, polypropylenes.
Mold a lot of LSR, which probably gives you the most capability when it comes to thin features. But it, LCPs is very common.
There’s some very [00:22:00] high flow. Peaks that we actually do with some high density connectors that we’ve been very successful with flowing around a lot of small features and doing some extremely thin walls with some of those high flow peaks. There’s also some Alt Tems that work very well too, so then high temperature resistance applications.
There’s some medical grades of that we use for a lot of things too, lots of different materials we can work with. Typically what we like to do is just work with our customers on the front end, see what their characteristics are they’re looking for, and generally just given our amount of experience we have looking at other designs and molding parts in the past we can usually point you in the right direction with a couple suggestions and go from there.
Jeff: And I think one thing The DFM team has done is not just looked at the single component, but taken on the whole device if allowed by our customers to look at the whole device and how the different components are interacting and come up with creative solutions for [00:23:00] not just manufacturability, but even functionality and such
Justin: Looks like we do have we’re going to allow Aaron to come on the platform. I don’t know if they call it stage or what they call it here, but Aaron I have you on stage now. I want Jeff, I want you to go ahead and Oh, there we go. We got him. Aaron, can you guys hear Aaron? Okay, perfect. We can hear you just fine and go ahead and ask your question.
LinkedIn: I have two questions do you guys have any issues with like molding over molding with plated parts, like gold plated, nickel plated, or Palladium plated. And then my second question, can you hear me?
Craig: Yep
LinkedIn: And my second question would be do you have any like material recommendations or again, any issues with sealing methods like glue versus ultrasonic welding versus laser welding?
Craig: Yeah, I think I think Jeff over here could probably nail those questions. That’s a great question. Thank you very much, Aaron.
Jeff: Yeah, Aaron to talk about plated parts, [00:24:00] usually that, they’re no problem for us. If they’re, when they’re plated over a substrate the thickness of those is so small that it doesn’t interfere with our molds at all.
The usually the problem we run into, especially with gold, as I mentioned earlier, is getting it to stick to anything. So those you often require mechanical features to hold those in place whether on the lead frame, but most often on the lead frame or the gold plated part. And getting the plastic to flow around those features to lock it in place and hold it in place.
But as I mentioned, getting it to seal is extremely hard, especially against gold because nothing really wants to stick to it. So that’s where we come in with our elastomers and overmolding the ribs and such into the component before it’s assembled. As far as assembly goes We have a lot of experience with ultrasonic welding and primarily ultrasonics is because how quick it is and how, Relatively inexpensive.
The capital equipment [00:25:00] is for an assembler to put those together. So an ultrasonic welder compared to a laser welder is a huge difference in the capital equipment. Recent vast advancements in laser welding though as far as speed goes, cycle times have come way down. The cycle time to assemble two parts with a laser weld versus two parts with an ultrasonic weld.
There’s not much difference there anymore. It’s more of the capital equipment involved. For prototyping and quick development
we can do ultrasonics all day long. It’s really quite quick. The trick with this, One of the key features with molding features with ultrasonic welding is getting the features that actually weld together or melt as crisp and as accurate as possible.
Not only do they have to be all touching at about the same time when they start welding, but a lot of those rely on a very sharp point or [00:26:00] at least a consistent point. There’s some going to more of a rounded point. But it needs to be the same and to get the, and even melt all the way around that perimeter.
If you have a feature that’s not quite filled out at one end of the part and it’s really crisp on the other side, it’ll start melting where it’s crisp and may not melt at all or weld at all on the far end or where we don’t have features filled out.
Craig: Yeah, and I can attest to that on the front end of things. I see a lot of, uh, components that have been prototyped other places. Low cost prototype molders, things like that. And I’ll work with customers and they always tell me, Oh, my gosh, I did. The energy director is not very good on these parts, I can’t get them together, and it’s so I can attest to that being a common issue.
Jeff: Yeah. Yeah, so we also have worked with customers that do laser welding, and that, that’s a wonderful process. Especially with the electronic components, one of the things to keep in mind is that the ultrasonic welding does induce [00:27:00] vibration very high frequency, of course, a lot of times we’ll work directly with the ultrasonic welding people to design out the vibration effects onto the electronic components.
One of those includes making sure that electronic components on the non vibrating side, or the base side, And locked into the fixture. So it it’s not on the vibrating side. So you won’t see damage to the electronic components due to that.
If they can go higher frequency and lower amplitude, that really helps save prevents damage to the electronic components.
And a lot of those require finer features that right up my Accumolds alley with the really fine detailed energy directors that can really start melting that at the higher frequencies. And as far as adhesives go that’s also something we’ve, we work a lot with. With our customers in finding plastics that are compatible with their [00:28:00] adhesives and even to the point of doing a lot of the adhesive testing for them with the plastics that we do mold.
UV cured adhesives are by far the most attract, attractable to your contract manufacturers because there’s no real setup time. You don’t have to wait for the, you don’t have to hold the parts together while the parts cure for adhesion. Half hour or longer. It’s a pretty much an instantaneous cure.
So you can take two plastic components, put an adhesive bead around them, and then hold them together and hit them with ultrasonic or UV and get that to cure right away and onto the next part. So cycle times are much, much less with the UVs and we’re more than happy to source prototype quantities in production quantities of.
Yeah, that’s great, Jeff. Thanks for mentioning that. And it’s very common for testing, whether it’s full [00:29:00] strength, leak testing, things like that.
Craig: That’s great, Jeff. Thanks for mentioning that. And it’s very common for our customers to ask for testing, whether it’s pull strength, leak testing, things like that. And one thing that kind of popped into my head that’s very common for us to be asked these days is conductive materials.
That’s something that we’re being asked to talk about quite a bit and and look at and I was wondering if you have any kind of insight on how you see those being used to make med devices low profile.
Justin: And as you get ready to ask that, I also want to make sure, Aaron, I want to make sure you got your question answered and if, and to check if you had any followups,
LinkedIn: Nope, that helped.. Thanks a lot!
Justin: Perfect. You definitely welcome to stay on stage in case you have any more questions. And then we’ll go back to Jeff.
Jeff: Yeah the conductive plastics and probably more interesting are the conductive elastomers that have some flex to them, especially for contacts really interesting.
We, we’ve started with ESD [00:30:00] compliant shells, for with low amounts of conductivity just to Eliminate any ESD problems all the way to where we’re carrying currents for sensors through plastics or through elastomers. And that there’s a lot of variety out there with what is used for the conductive material inside the elastomer or the plastic all the way from.
nickel to carbon fibers to nickel coated carbon fibers. Some really high end materials. We’ll use silver beads with really outstanding conductivity results, but the cost of those is usually too high. So what We often work with customers on is how much carbon either fibers or powder do we put into a Resin and balance that out with the durometer.
So if it needs to have Some elasticity, [00:31:00] say for a seal or even for a contact to sensor to connect from one point to another maybe you need a software durometer. So in case the wearable flexes that you’re sure that elastomer stays in contact with the components you’re trying to connect there.
It’s really an innovative way to get around using a a steel lead frame that’s been plated. Sometimes you have to use that it’s hard to beat a gold plated lead frame from point A to point B. The resistance is negligible. Especially for batteries and such you’re probably gonna need that, but there’s been a lot of developments with how to load elastomers to maybe even connect, connect higher current carrying devices and inject those right into the the shell of a wearable.
During the molding process and when you get the component, you’ve got the seal and connector all built into one, one component.
Craig: Oh, that’s great, Jeff. And there’s a lot of things to think about there and a lot of kind of design options that a lot of people don’t really know are possible. So [00:32:00] great to hear things like that from a guy like you that works a lot on the front end with all of our different customers when it comes to designing new products, product development like that.
So really appreciate the insight there.
Justin: All right. Seeing is I think we worked through our message questions. Correct. Worked through all the questions. Worked through the questions on stage. We obviously appreciate everybody participating today. For those that are listening publicly and viewable, and for those that are hidden listeners, we appreciate everybody. I will say This will go back on accu-mold.com. The website will also be posting some select clips on link right here on LinkedIn.