Comparing Casting Production Processes
Which production process is right for me?
I think we can go ahead and get started. I had a few things to cover before we start. So, with that, I’m Taylor Topper, a content strategist here at Dynacast, and your hostess for today’s webinar. This is our fifth webinar, and our new metal solution series. So if you’ve missed any of our previous die casting or metal injection molding seminars, we do have the video recordings and the presentation slides available for free download on our website. It’s Dynacst.com/webinars, and before we get started, I’d like to go over a few items so you know how to participate in today’s event.
I see a lot of the familiar names, so thank you, everyone, for joining that have joined us before in other seminars, but in case you do not know how to participate today, everyone is muted to cut down on background noise, and you’ll have an opportunity to ask questions at the end of the seminar. I encourage everybody to ask questions throughout the seminar. You should see a screen that looks like this in your control panel. You can enter your questions here, and then we will get to them at the live Q and A session at the end. I’m also recording this seminar today, like usual.
I will send out the slides and the video recording by the end of the week, so be on the lookout for that email from me. With that, I’d like to introduce Daniel Perreault, one of our engineering managers here at Dynacast. He has been with Dynacast for over 26 years, and is currently responsible for all engineering and tooling related activities, from initial quote, to value-added, and value-engineering seminars, managing the APQP team, and design and build of new tooling programs, with additional responsibilities in overseeing ongoing repair and maintenance of production toolings to support manufacturing.
Daniel joined Dynacast in his early days as an intermediate tool designer, working his way up to program manager and then engineering and tooling manager while at Dynacast Montreal until its close in 2008. From there, Daniel took on a key support role and oversaw the engineering departments for both the Dynacast Lake Forest and Mexico facilities, traveling between both for over two years. Having departed from Dynacast for a short two-year period, Daniel rejoined Dynacast as the engineering manager for the Peterborough facility, where he maintains that role currently.
Daniel has extensive experience in working with customers in value-added, value-engineering designs for new programs, assisting customers in reducing costs on component parts and downstream operations. Daniel, thanks so much for joining us today and sharing your knowledge.
Well, thank you, Taylor, for the introduction and also hosting this webinar, and I would also like to say big thank you to all who are online and taking the time away from your busy schedules to partake in this seminar.
Great. Daniel, before we get started, I have a quick poll for everybody. Since this is a seminar comparing other production processing to die casting, I just wanted to launch this quick poll, if everybody could take just a quick second to answer it. What type of process are you currently using to create your components, whether that’s die casting, powdered metal, machining, plastic injection molding, or other?
I know that there’s quite a few different ones. I thought this would be an interesting way to start the seminar. Here are results for everybody who is on this seminar today. Plastic injection molding, not surprising. Daniel, we were discussing that powdered metal only at 7 percent, which I think is a pretty interesting percentage. With that, we’ll go back to Daniel and the agenda, and I’ll hide these.
Well, thank you very much Taylor. So, basically, today in this webinar, we’ll cover conversion opportunities resulting from mainly six processes. So the first one will be plastic injection molding to die cast, and forging modern metals, machining, overmold IMA, and minimum investment casting. So, from there, we’ll go to start on the process here. So wanted to have a quick review of the die cast technology for those who may not be aware of the process and how it works. So the first main part of the die casting process, we got two main processes.
We got a hot chamber and the cold chamber. The hot chamber is used for lower melting alloys, such as zinc or a little higher, as well, for magnesium, and the way the process works is that you have an injection type molding machine. So it’s a die cast machine with a fixed platen, a movable platen, and in between the platen sits the die cast tool itself. In front of the machine over here, we have a molten pot where we have the zinc alloy, where we have a gooseneck which is submerged into the molten zinc connected to what we call here a nozzle, introducing the alloy into the die cast tool.
On the shot end side or the gooseneck above that, we have what we call here a plunger which is activated through a hydraulic cylinder with pressure over here. So what happens is that, as we make a shot, the hydraulic cylinder will come down at very high speed...sorry, as we make a shot, before shot, we pull up this hydraulic cylinder, and we will suck in the molten alloy or zinc into the gooseneck. Then, as the plunger goes down, it will close off the entry valve or fork, and it will push the molten zinc up to the gooseneck into the die cast tool.
Once the molten alloy in the tool is frozen, die cast tool will open up, and then we will inject it. Die cast, it also has a unique technology which is four-slide hot chamber process. The back end or shot end of the machine is similar to what I just described minutes ago, but we have the unique technology of having a cross head on our machines over here which can encapsulate four movements right into the tool on the machine. There’s no need to design and build mechanical core pulls or hydraulic core pulls as auxiliary slides that are required in a die cast tool on the conventional side.
So this allows for very precise tooling at high speeds and also lower tooling costs. The next part of the process capabilities for the die casting is a cold chamber process. Cold chamber process is mainly used for aluminum alloys where the melting pot temperature is much higher. So in terms of the machine itself over here, it’s the same type of machine, except for the shot end. Typically, what happens on the cold temperature machine, we have a crucible, which is not connected to the machine, which is offline, where we have the molten alloy, aluminum alloys into the molten bath.
From there, there is a connection from the crucible to the machine by means of what we call a ladle, which is actuated by mechanical means, with the ladle going to the molten bath, scoop the alloy, come over, tip over, and fill in the shot sleeve over here with the molten alloy aluminum. From there, the hydraulic cylinder will move forward, bring the piston forward, and inject the aluminum into the die cast tool itself under high intensification to make sure that we have a good filled part. So that’s a quick overview of the die cast process in the hot chamber and a cold chamber.
When we compare the die cast process and the injection molding machine, in terms of the machine front end self in terms of the plastic and the tool, which is referred to a mold, it’s pretty much the same process where we do have differences on the machine, where the plastic is fed into the tool, but typically, an injection molding machine is actuated with a screw with a hopper on top. So the plastic granules are either put in the hopper and fed down by gravity or by a vacuum system. The granules will go into the screw. They are heated up, and it goes into a molded state, and the screw will turn and fill the cavity until the plastic is solidified.
Plastic Injection Molding
So let’s start with some of our conversion opportunities. The first conversion opportunity I would like to talk about is a plastic or injection molded part to a die cast. This is a customer which came to us not too long ago. They were launching a new product to the market, and they were failing, having issues preventing them from going to the market. The main failure, there were two components, and there were issues with the strength of the injection molded components. So what we did with the customer, we sat down, and we learned about their application, and we designed a part for the die casting process.
So we worked with them. We worked with the 3D models. We provide them 3D models of all the changes for flats for gating, for part lines, and so forth, and before going into cutting actual production tools, they would need to validate this, as this was a high-profile program with major testing that had to happen prior to launch to the market. So what we did with the customer is we worked with them through VAV design 3D models, and then offered to them a prototype solution.
So, with them, there are multiple ways we can prototype zinc die cast components prior to hard tooling. In this case here, what we did is we worked with them and provided them a spin cast solution rubber mold. So we went ahead, and we made 150 components of both parts and got them plated internally here and provided them with these samples here. With this, we were able to do some assemblies, design and validation tests to quantify the design was okay for the die cast process. From there, there were small, minor tweaks, but I’m pretty up front with them and did a pretty good job in designing the part for die cast process.
Once we had all their validation complete and so forth, we were able to go ahead and build production tooling, and what you see here on the right-hand side are the actual die cast parts themselves as a finished state with the plating. These parts are in Zamak 3, and they have to pass a 240-hour salt spray test, and these were plated with a yellow gold super seal alloy for 240-hour salt spray test. You’ll notice that these parts are pretty much right off the machine.
There’s no secondary, so they come out very, very clean, flash free. These holes here are very, very small, as you can see here, 32 by 25 thousandths of an inch, and there are four of those, and those are very critical to the customer. As the gases flow through there, and they have to past through so many cubic millimeters per minute to be able to have a product that will work on the market. So we helped customer resolve their failures and be able to launch to the market by converting an injection mold component to a die cast component.
The other areas which were successful and can do conversions from forgings to die casting. Forging is a slower process than die cast. Typically, it’s not as precise dimensionally. It’s also a slower process. However, you do get some very, very high density depending on the application that you’re looking for. In this case here, this is an automotive dust cover for customer. The parts were forged, and then they had to do a lot of secondaries with the threads over here on the outside.
So I’ve been working with them through VAV, understanding what the application was and knowing what was critical, what’s not critical. We designed a part for the die cast process for the end gate injection and tooling. This part here, as you see, this is right off the machine. These parts are die cast and are the multi-slide machines. They come out of the machine, and they pretty much fall in the box, and then we go out, and then get the thread sealant applied on the outside, but as you can notice over here, there’s an O-ring that goes in here.
The faint line over here, that is your part line. These threads over here are not machine. They come right off the die cast machine, so it’s die cast in the box. We add the sealant. Then it goes to the customer. So we’re getting a net-shaped part out of the die cast tool, okay? It’s really what we really aim for when we work with customers up front. In this case here, this is an M34 by 1.0 6g thread as cast no interruptions, and this part line here flash or bur, we need to maintain that at 0.05 millimeters or less.
The other process we’ll talk about or conversion is from machining to die cast. Machining is used extensively, as we all know, but as you machine, you got to start from a platten material that chips away, so you have a lot of wasted material. It’s a slow process. Screw machine can, however, compare in terms of cycle times to die casting, but again, you got a lot of chips that need to be cut to be able to come to the finished part. This is a machined aluminum die cast part, which was made of 6061 aluminum, which we convert to die casting process. So the customer was experiencing a few issues.
First one was the lead times to get these components machined with the high cost, and as we learned more and more with the customer as to what the part was that was functioning, we learned that they were having issues on the field with this screw over here. This part here is a locked mechanism, and the depth of the thread needs to be kept very, very tight. They were not able to maintain a constant depth on the thread, and they were having field failures and also customer dissatisfaction due to poor performance. So as we found out that this was the case, we sat down with them, and then we redesigned the part or adaptation part with the square hole through adding a slide in the tool.
So now when it happens that when we come in tap it is not critical any longer. We just have a screw that is forced to come out, and they now have a full repeatability on the screw here within one-thousandth of an inch part to part, which has eliminated our quality issues and customer satisfaction issues. This part also had large cost savings to them, as you can imagine, machining this from a piece of block aluminum to net shape die casting. So this tool is being built right now.
The next example is an overmolded die cast assembly, which we convert to a one-piece die cast. This is an automotive seat adjustor. The customer were casting the spin in here very early on in stages, and they were setting this out to be overmolded with this gear over here. They were experiencing wear issues on the gear, but also noise issues as the gear worn out. So what we did is, in working with them, we redesigned the assembly and came up with a one-piece solution. The one-piece spinning gear eliminated the wear issue.
The noise issues also went away, and we also eliminated, you know, the logistics of working with second supplier, of freight, inventory levels, and so forth. The internal diameter over here, as you can see, is a plus minus 0.01 millimeters, and we cast that to size. These parts over here are manufactured in multi-slide equipment, and we’re able to size this right at the machine. So, again, this is a die cast and in the box as the die cast machine. So there’s very little, or there is no post-casting labor or processes required, which makes the part very, very cost effective with very high cycle times.
The next case is a powdered metal to die cast. It’s an automotive locking nut. By visiting their customer about eight months ago, we were walking their lines and doing some...review some programs, and we came across this part that was a powdered metal on the floor, and looked at it, and said, well, why can we not look at this as a conversion opportunity? So we sat down with them, and they were very interested in looking at this because it was a high cost item for them, and they also had to do secondaries on the thread.
So we sat down and ran some numbers for them and came back with this solution over here. It’s an M90 thread, so it’s a fairly big part. It’s about, you know, three and a half, almost four inches in diameter, and we’re able to provide to them a die cast finished component. So it comes out of the die cast machine. It is degated and right in the box. M90 by 1.5. So what they’re doing right now is we were able to provide to them some process by mean as producing a prototype tool.
These parts have been going under test now for about six months. The die cast parts which are net using 5 have met or exceeded the current powdered metal part in terms of performance. It’s going through a last test right now for creep Actually there is creep test, and that should complete in the next month or so. This part over here conversion is resulting into a half a million dollar US in annual savings based on one new piece a year.
So by us walking their facility and being able to see what they produce on the floor, we’re able to bring up an opportunity for them to give them a savings of a thousand dollars on one part, and there’s a second part right now which we reviewed, and it will move ahead as well, which will also represent an next 450 thousand dollars in parts as the sales savings-per-year basis. The tooling for this program investment will bring to the customer a six-week return on investment for this program based on the cost savings.
Overmold to IMA Assembly
The next example is an overmolded shaft to IMA assembly. This is a part that was injection molded with a shaft into it. The customer was having issues with a part due to size loads where the shaft was going out of axis alignment, and the parts were failing in the assembly, and so what we did is we worked with the customer, redesigned the part for the IMA process and tools, and so forth, and we were able to provide to them a same diecast part overmolded with a steel shaft. So that has eliminated the performance issues and failures they were having in the injection overmolded to steel shaft.
The next one, this is a dual conversion PMI, powdered metal injection molded. This is a part for the medical industry. It’s a dispenser for drugs, for insulin. This part over here, the gear itself up to the back over here is a powdered metal, or was a powdered metal part, and then they would overmold this cap over here. Now, you don’t see it over here, but the reason what they were overmolding this cap is because in the back over here, you got some undercuts. You got some spherical domes which is required for the dispensing of the units.
They were also experiencing premature wear in their assemblies with the parts because the powdered metal part had the part line cross over here, and it was eating away at the plastic. So we worked with them extensively, redesigned the part, and were able to provide them this one-piece solution with an added advantage of no part line right on the teeth. We were able to design a tool with the part lines on the outside, and there’s no part lines flash or burrs.
These parts, again, come out of the die cast machine right in the box and have some very, very tight parts, as you can see over here. The teerh are 6 thousands radius with plus minus one fifth and again, the advantage of having this in the one slide gives us a net shape operations. So it was a cost savings to the customer and also a very high increase in terms of performance for the dispenser.
So that covers all the examples that we have. This slide here is kind of interesting. It shows you where different processes can come in as being exciting to your selves.
On the left-hand side here, you got the volume over here and then the part complexity. As you get more and more to higher volume and complexity, then the MIM, or metal injection molding process, gets to be very interesting. Dynacast, besides the die cast process, can also offer two other processes. One of them is MIM, and the other one is investment casting. The MIM process, this is our sister facility. They were able to work with the customer to convert from machine to MIM.
And they were able to consolidate three parts as one, which we use the assembly cost, increased productivity, and came back with a savings of up to 1 million dollars per year to the customer. The other area we can also support you is with investment casting. Dynacast made an acquisition earlier this year of a company called Signicast, a large investment casting facility, and this is one example that they were able to work with a customer from, on the left-hand side, with a machine part, and by working the design with them, we were able to eliminate machining assemblies staffing and result in 22 dollars savings per part number.
Initial processes where Dynacast comes into very good hands is with plastics, although die castings are stronger. We can run faster cycle times, heat resistant, and chilling properties. Sand castings, die castings provide better tolerances, better surface finish, and less labor cost per casting. In terms of forgings, die casting can produce more complex parts, shapes, thinner, and holes can be cored. For stampings, die castings have better part-to-part uniformity, less trap and closer tolerances, and through machining, die castings have fewer operations, less trap, faster cycle times, and offer better part-to-part uniformity.
So what makes a good conversion to die cast? Complex machine parts where you need a lot of material out, Die casting can be very, very competitive, and it presents some very good cost savings. Converting multiple parts into one piece net shape. So if we get involved with our customers up front early and get to know the application and your downstream operations, we really excel at working with our customers in redesigning the part, and can eliminate multiple parts or processes down the road. Parts requiring high strength mechanical properties. Multiple alloys are available, which we’ll cover here shortly for those properties.
Design for manufacturing assembly looking at operations for assembly and how we can eliminate some components that you may have to purchase through design of innovative die cast design. Part-to-part repeatability, quality, and very tight tolerances. Very high Cpk data can be held on a lot of parts, and part-to-part repeatability is very, very high. One thing that Dynacast is kind of unique about it shit material selector, and I’ll just go offline over here for a second here and bring this up. This is our Dynacast homepage which has some very valuable engineering information, and if you scroll our page over here, as you see here, this is our multi-slide machine, our small A2 machine.
You could see the cycle times that these machines are producing. This is live cycle times, and we can run one cavity up, in some cases 10 to 12 cavities. Some of these tools will run up to 50, 60 cycles per minute. So very, very fast cycle times, and a very, very high part-to-part repeatability. So if you keep on scrolling down over here, you’ll come up to our process metal selector. If you click on this page over here, this tab, you’ll come up to this page here, what’s called the dynamic process metal selector. What this allows you to do...my computer’s a little slow over here for some reason. Here we go.
You can take these here and drag these along over here to the mechanical properties you’re looking for, and you click on show results. That’ll give you all the die cast alloys that will fill or meet those properties which you’ve dialed in on top of here. So it’s a great tool for the engineers to look at, based on the mechanical tensile and so forth, what best alloy can I go with. You click on the die cast metals here, it will briefly talk to you about three alloys that we can provide. Hot chamber, which is zinc, aluminum for the cold chamber process, and magnesium through the hot chamber process.
If you want specific information in regards to the physical properties, then the die cast metal properties sheet over here will talk about all the alloys with the mechanical properties, and you keep on going down onto physical properties, compositions, and so forth. This is a great reference, as well. A lot of people do ask, you know, how do you control porosity or mimic, you know, the die casting process up front when you do the design, especially on high cosmetic parts or high strength, low porosity parts.
We do have tools that we work with, and one of them is a flow simulaton program, and I just want to present this real quick. So on parts on all those tools that we design and build in house here, we will run a MAGMA Flow Analysis, and it’ll help us predict the flow path, also determine where the air pockets or if there’s any air entrapment. So before we cut any steel on the tool, we’re able to simulate the flow pattern, make any adjustments on the tooling in 3D, reevaluate that, and confirm that through this MAGMA process over here. So very, very strong tool for us which allows us to first time with the tool be extremely close to where we need to be in terms of the finished product. Go back here to this presentation, and back to you, Taylor.
Thanks so much, Daniel. That was so great. I have just two questions, and right now, actually, I answered a few during the presentation, but just as a reminder, everyone, any questions that you have, you can input them here on the questions pane. We’re going into our live Q and A section of the seminar, which I always think offers a wealth of knowledge. So, with the first one, I think we kind of already answered it from the website, but what materials can you die cast?
I’d encourage everybody to take a look at our website. We have a lot of information I think compared to a lot of other die casting companies. We have a knowledge center with case studies. We have our metal selector tool. We have white papers. There’s just a ton of information that you can gather on there, but Daniel, I don't know if you want to add to the different materials that we already went over or if you think we can skip that one.