We have been doing this for years, yet I still get excited when the new prototype parts arrive. It does not matter if they are 3D Printing or CNC, or like these, MJF. All are the parts of 2 new custom machines.
In these few weeks a lot of special parts for the new custom machines are arriving. They look just like the CAD models, of course, yet holding them in your hand, gives a sense of accomplishment. Today some more of the rapid prototype parts arrived, all neatly packaged, and they are pretty cool.
The Cool Factor extends beyond having the physical parts. Certainly, part of the Cool Factor is doing things with these parts - relatively inexpensively - to accomplish complex functions in a super clean and wonderful way. While these are made with prototyping processes, these are machine parts that will run for a long time. That is Cool.
Prototype Parts For New Custom Machine
The current big projects at Synthesis include 2 new Purpose Built Machines. A smaller-ish one that will become a production product at some point (made in quantity), and a larger one that will probably remain as the only one of its kind in the world. (It will quietly pump out parts for this customer the next many years.)
While I can't get into the details of what these machines do, I can say the bigger machine will speed up a process so our customer can respond more quickly to filling the needs of their customers. They have a time and space consuming process identified as a bottleneck in serving their customers, and making their parts. After discussing it with us, a new custom machine is an excellent solution. It is not a simple machine, but it will drastically change the time, space and accuracy of their process.
This is why we love designing and building custom machines.
The prototype parts shown in the images are pieces of a new machine. While rapid prototype parts like SLS are getting better with new equipment, we must still consider how they are used. These particular pieces are made with HP's MJF 3D Printing to hold and locate sensors, and to attach a motor.
Strength of the material is important, as is longevity of these prototype parts. But they are up to it. Reinforced with steel liners, this part made with 3D printing technology is so much faster and cheaper than making something CNC, for instance. - And we can add some style to make it look nice without any extra cost.
This process has proven itself with us many times with one-off parts like these. Cost and time do not even compare. Extra function is easily added to make the parts do more with less.
Solutions By Mixing Technologies
MJF is a nylon base, so the parts are pretty strong. If they are thin, then they are somewhat flexy, but thicker and with ribs, the parts become quite stiff. The fun thing with rapid prototype (RP) parts like this, we do not have to worry about one area being thick or thin with respect to other areas.
We also do not worry about moldability or machinability or those kinds of things. As you can see, none of these parts would be easy to machine or to mold.
The downside is they are still plastic, and less stable with less strength than full molded plastic parts. Our task, then, is to use the prototype parts in ways that enhance the material, and make sure we are not asking it do do something it will not do well.
Strength is a misnomer here. True, the prototype materials are not as strong - given a typical thickness - but we can just make them thicker, and add ribs for strength and stiffness in ways that are not possible in molding. So here, these parts are actually stronger than similar molded parts.
In the motor mount, we want the complexity that is easy with RP, but we do not trust the long term stability. The motor has some weight that will rest on the mount, so stability over time and under load is important. Certainly we could design the mount in aluminum or another CNC style, yet RP offers time and cost saving for these complex pieces.
So, the solution is a mix of 3D Printing and CNC Machining. Note the steel sleeves that support the loads.
Building With Prototype Parts
To get the best of both worlds, we simply design the part with steel sleeves that glue into the MJF. The sleeves hold the bolt loads - and therefore the cantilever weight of the motor. Then, the RP material will set the location and carry the motor reaction torque. The MJF then gives the opportunity to put some style into the shielding and other functional features into the prototype parts.
The mixed materials approach allows us to make the simple metal pieces to hold the motor weight and bolting loads without worrying about creep for plastic in the prototype parts. The MJF will do great with the transient torque loads. By combining the prototype technologies, we will get the stability of metal with the easy complexity of 3D Printing. And, we still do not have to obey the rules of making the parts manufacturable!
Besides being a cool looking prototype, these are quite functional and make it easy to solve some interesting challenges of the new custom machines. For us, this is all part of Product Design and Development in serving our customers. Win all around.
Let's hear it for technology advancements, and for creative thinking to get more for less.
Leave your comments below. We would love to hear about your successes as well.