VPI 3D tonearm

Dear Lew,
In welding......the norm is not to use 'foreign' materials but to create a homogeneous 'whole' by melting together identical materials. The strength of these welds can be designed to be identical to (or even stronger than) the two pieces being welded.
However....there is a chance that there are changes at the molecular level of the 'welded joint' which, whilst not affecting strength, performance or visuals......could possibly affect the acoustic properties or integrity of the whole?
With 'gluing'......I admit that there would be an acoustic change at the interface of the adhesive medium.
Points taken :-)

Much depends on the nature of the joint. An abrupt change in section will have acoustic consequences, either good or bad, whatever the method - 3D printing, welding, gluing or otherwise.

In the case of some 3D printing, lasers are used to fuse the materials which is not much different from welding.

Some glues are stronger than the materials on each side of the joint, some are flexible. Some are solvents which allow the material to dissolve and reform...

Anyway, Two things are certain: (1) The early adapters will be ecstatic over this tonearm, and (2) we'll be arguing over why that is.

What I find so interesting is that HP (VPI) is judged so harshly. I don't think anyone has had such success in such a niche market. Success/failure of this arm will be better evaluated in time. With all this interest on these and other audiophile pages, I'm sure everyone will be given a voice.

As far as material is concerned, isn't Continuum tonearm using similar type of material? I thought somebody even mentioned in the past that Copperhead arm may actually be the first 3D printing arm or at least used some earlier technology along 3D printing line?

I don't know where you appear to have obtained your 'information' as there have been numerous reviews and articles about the Cobra and Copperhead arms over the last 8 years with not one of them ever mentioning '3D Printing'?

The Cobra and Copperhead armwands are 'Reshape' Shape Optimised, Resonance Tuned Compound Curve Wands from proprietary woven fibre technology pioneered by Continuum Audio Labs.
The wands are unique monocoque construction using advanced fibre and resin technology proprietary to Continuum Audio Labs.

"Woven fibre and resin technology" is currently not able to be utilised in 3D printing.

If Continuum HAD in fact developed the first 3D printed tonearms......Harry Weisfeld would look pretty silly making such a 'song and dance' about it 10 years down the track?!