3D Printing Assemblies (How Do They Do That?)

I'm pretty sure they 3D print the parts and then assemble them.

Difficult to do with the extruded material type of printer but not with the laser fused powder or liquid type. You can drop the platform down to allow a layer of powder or liquid to cover the part surface, then start creating the loose part within the overall assembly. Some features may need anchoring webs to hold them in position & these will have to be removed later. Example here this particular printer can also print supports in wax within the assembly so that they can be melted out afterwards.

Zcorp 3D Printer 650by AmboTechnologies1,363,302 views

When stereolithography was in its infancy back in 1980's a gearset similar to the one shown was used as a demonstration of the capabilities of the new technology.

I was one of the original applications engineers hired when 3D Systems opened the first three regional sales and support offices. In the 3 years I spent with them there was no way the first two iterations of SLA machines could practically build even a semi-functional mechanical assembly. That gear-set was not a part of our standard demonstration repertoire in that time period.

Even the simple ball in a cage toy we used as giveaways was built as a single piece with the ball cut loose and the ball building supports hand finished out of the assembly.

I've been out of touch for a long time so I don't know when, or even if, SLA systems were made capable of building operating assemblies. That facility certainly wasn't available in the 20th century.

And no, we didn't have colors available then, either. I don't think that option became available until well into the 90's and even then it was one color only per build. The resin vat in the machine had to be changed out to change colors. Any parts that were finished in color in my time were done in a model shop atmosphere. Both of us AE's in the eastern region office were journeyman machinists and quite capable of replicating commercial products in the SLA and post processing.

Hooker

The part to which I referred was all one color.

I did not witness its manufacture.

Maybe the engineer who brought it to show to us was not truthful.

I don't know.

I would put it up to misunderstanding. All of us AE's were making too much on the commission side to risk it by lying. There were 9 of us AE's at the beginning and I would have trusted any of them.

Now, regarding the salesmen!! That's a different story. We all know what they say about a salesman's lips moving, right?

No doubt poor memory. It was almost 40 years ago. But, I do remember that it impressed all of us jaded engineers.

We thought we were hot stuff, building secret satellites and spy gear. It was a very cool job. (Couldn't even tell the wife what we're working on)

I have a sample from one of our local machine shops which consists of a 6 way cross trapped inside a cube shaped cage. All outer corners are chamfered & all faces engraved. The cross is loose inside the cube but does not come out (we've tried hard). This is machined from aluminium on a conventional CNC machining centre. The final cut across the end face releases the cross.

Yeah, I've made plenty of those, usually when commissioning a new multi-axis machine or when demo'ing for a new potential customer. They seemed to be a standard testing program delivered with the machines way back when.

Like this in titanium from Oak Ridge.

https://youtu.be/0yq9jhHklRo

I was at a 3D printer demo meeting last week and they print a sugar based "support" material as well as the plastic. This allows free moving gears, unsupported angles, and very complex parts. Wash the final product in hot water and presto! wheel on a shaft inside a closed shape and it is free to turn.