The Problem With Mass Production Metal 3D Printing

There are a couple of reasons metal 3D printing hasn't caught on. The way it was hyped a few years back and we're going to talk about that a little bit. Metal 3D printing has gained a lot of hype. So much hype that I cannot go into a meeting where we talk about FMD 3D printing,  mass production, and 3D printer farms without somebody asking “Are you ever going to do metal?” and the answer is at this moment no. 

We really don't anticipate doing metal but there's a reason for this. Metal 3D printing still has a very large technological hurdle and the problem is it is not necessarily an engineering technological hurdle. It's almost a scientific-technological hurdle. The difference between those is an engineering hurdle you can see and you can say okay if we work at that here's kind of a solution we'll figure it out there's a pathway to it. a scientific-technological hurdle is we have got to figure out how to do fusion. There's some fundamental piece of science that isn't figured out or so complex that it doesn't really work.

 With metal printing whether of all the processes that exist ultimately what they always come down to is you have metal powder suspended in a resin a binder you then print out the part which is then a green part which is just a glued together metal powder you then take that glued together metal powder and you either D bind it you get rid of the resin out of it and then it holds its shape and then you put that into a centering oven. The centering oven melts all the particles of metal together. You eventually end up with what is essentially a cast metal part that could either be machined down a little bit more or something along those lines. Here is the problem the first part of the process the binder jetting or the bound powder that's fine that works great that's very well proven in fact we print parts like that very often the D binding is also not a problem the binding and removing that binding material is very easy heck you can put it into the center and just have it burn off. The problem is in the centering of it. Here is the thing in order to center apart reliably you have to know every single detail about that part and that part needs to be exposed in an oven to the perfect amount of heat but not too much.

 If you have something like a dumbbell or a kettlebell that you see at the gym it has a handle on top of the ball of metal on the bottom if you are making a part like that in a centering oven you run into a problem of the inconsistency in the geometry itself to where the handle is going to heat up and bind much more quickly than the big old mass of metal down at the bottom. You have to design for the centering process so that the whole thing can be baked at a regular level. Another analogy to this is cooking cookies if you have a bunch of small cookies they will all bake in 15 minutes but then if some kid comes along and puts a little dollop of dough on your dish now you have to bake it for a half hour to get all the stuff cooked and bound together. the baking of metal parts is causing a lot of problems because the rules change with each new part. If you're doing watch faces you can load up a thousand watch faces and figure out what is the formula and the recipe for baking those watch faces a thousand at a time inside of that oven but then if you take it down to 500 well the rules of making then change or if you change to a different watch face or a different type of part then the rules of cooking change again and this is the problem that metal 3d printing has had. The science of what is the correct way to bake something comes down to art like a lot of 3D printing. The guys eyeball it and they're like ah it's not quite done cooking yet we got to cook that for a little bit longer. There's not enough intelligence or enough science available to really quantify every possible variation that 3D printing can create and what has happened is that for companies that are pursuing mass production of 3D printed parts they work fine and they can do it but the problem is they are not very flexible because they're able to do a thousand watch faces but you can only run a thousand watch faces at a time. That's how the line is set up you print them over here you do bind them and then you bake them and that oven is set up for a thousand watch faces at a time and nothing else. If you ever change what you're making the change might be a bit easier than doing a new cast of new bowls and that kind of thing. It is a big change because you have to recreate a new recipe for the new part and this is what's slowing down metal 3D printing adoption.

The current process of metal 3D printing works fine at a smaller scale for shops and even hobbyists. It's not that big of a deal because again you can eyeball. It's part of the gig machine in itself and sometimes has some creative and artistic flair to it. It's not necessarily a hard science, but for a process to reach mass production, it has to be hard science. If it wants to hit the goal of 3D printing which is high flexibility then it really has to know the science. Metal just isn't there yet and it's a fundamental problem that the industry has to solve before it's really scalable and to replace molding or casting at a large scale. because it has no more flexibility. The 3D printed metal machines for mass production are essentially large metal injection molding machines so unless you're making a part with a unique geometry that requires printing to create that geometry there are very few benefits to it over regular casting. We keep an eye on it and we're really excited about what everybody is doing with metal but it is just still too early and it has this fundamental problem of how to cook a part and do it flexibly and reliably that just hasn't been flushed out yet.

 That's kind of the problem with metal 3D printing. Comment down below if there are other components of 3D printing or other parts of the industry that you want to talk about and we'll try to get them answered. 

Happy Printing!