Is 3D Printing The FUTURE of Manufacturing?November 25, 2017, 11:36 am
November 25, 2017, 11:36 am
December 8, 2017, 11:05 am
Thu July 9, 2020, 3:07 pm
Thu July 9, 2020, 3:07 pm
3D Prining is about to to take over traditional machining the same way CNC Machining took over manual machining.
Eventually 3D printing will replace casting too.
Since 3D Printing does not require complicated setup and programming, this in turn will lead to massive loss of machining-related jobs.
Read more to see if this is true!
There is an interesting topic over at Practical Machinist forums that I took a small part in.
The topic itself is quite a long read, so I decided to compile different opinions into one small article.
First of all. For those who are not familiar with the term....
What is 3D Printing.
(Valve block Courtesy of www.vttresearch.com)
3D Printing (later in this article as printing) is a process of producing a part by adding layers of material (contrary to machining) from bottom to top.
It is also known by a broader term as additive manufacturing.
What are PRO's of Printing and why do we need it at all?
Since very few people make a living machining plastics, we will discuss relatively new Metal 3D Printing.
One of the main benefits of Printing is ability to create shapes that are not otherwise possible to create by other means.
High-performance car manufacturers and aerospace companies (NASA 3D Printed rocket engine in the thumbnail) manufacture parts that have internal support structures that are near impossible to cast or machine by other means.
Medical prosthetics companies manufacture artificial titanium and plastic custom-made limbs that and light and strong at the same time.
You must have noticed the trend: Printing is great very small volume manufacturing, where complex shape of parts and design complexity make other forms of manufacturing not viable.
But that is not it!
Lately several companies are making headway in increasing the scalability of production metal Printing.
Scalability is the ability to quickly increase the number of produced parts with minimal increases in production equipment.
Injection molding, for example, scales great. Molding machine can pop out multiple parts per cycle with each cycle taking very short time. (depending on many parameters like size, material, cooling etc. but measured in seconds).
Want to produce more parts per cycle? Simply add more mold cavities!
CNC Machining, on the other hand does not scale well. A single spindle can produce only one part any any given time. If you want to make double the number of parts you need to double the number of spindles. And there are 2 spindle machines for that.
So where is Printing on scalability?
Not surprisingly Printing does not scale well.
Not only parts take longer time (hours not minutes) to produce. But you also get the same issue as CNC machining - one machine can produce only one part at any given time
And this is where some companies are promising huge advancements lately.
Check out this one for example: https://www.desktopmetal.com/products/production/
They claim to be close to providing technology, that really looks like traditional inkjet printing. This allows the carriage that deposits the material (and also applies binder and dries) layer by layer to print multiple parts per pass. So printing 10 parts versus one part will not take that much more time.
(Image courtesy of desktopmetal.com)
So just how strong the Printed parts are? Are they able to withstand high pressures, vibrations and all kinds of loads that parts in demanding applications face?
Well, apparently they are.
Check out this promo page showing the characteristics of the materials they can print: Direct Metal Laser Sintering Materials
These numbers are indeed very close to normal bar stock, that is provided by a foundry.
Also check out this article in MMS Online (page 70) about CIMP-3D using laser fusion 3d printing in manufacturing flight-critical part for a Navy helicopter.
If you check the article, however, you will notice that in this particular case the printed part almost defeats the whole purpose of printing:
(Before and after machining. Image Courtesy of MMS Online)
It is easy to see that the printed part has only rough features and requires considerable after-machining to get all the surface finishes and sizes just right. The as-printed part is no where near the condition that would let in anywhere near a helicopter engine!
To be fair this part was just a proof of concept that a 3D printed part can be approved to be used in such a high-demand application.
The elephant in the room that Printing companies do not want to talk about is the subsequent after-machining, that many printed parts require in order to get them ready for shipping to customer.
This is the reason that not some machine manufacturers (Mazak, Mori, Matsuura) produce printers that combine traditional machining and 3D printing.
It is no secret that inhaling fine metallic dust used by most printers may not be very good for ones health.
Yet there will be need for someone to handle such dust.
And there will be a lot of that need on many stages of producing the part. From preparing the raw material, to subsequent sanding and machining to recycling.
So considerable investments in developing a safe workplace will need to be made.
After research this topic I believe 3D Printing has its place in a machine shop. But it is nowhere near the point where it is going to cost machinists their jobs an masse.
Just like Investment Casting for example.