Pressing Blanks from pvc Compound

[leethal]

A forum search turned up very little for me so I'll ask the great unwashed. Has anybody attempted pressing blanks for lathing from pvc compound? Seems like a great way to make a few dollars, and cheaper than the better alternatives I've seen ie souri etc I'm wondering why pressing plants dont do this already....Surely the sound quality would e better than cnc'd poly and acrylic.

What do you think would be critical/prudent when attempting blank plates? Silvered and nickeled stampers copied from a disc of glass? Or simply a highly polished disc of stainless steel?

[The Shank]

Surely the sound quality would e better than cnc'd poly and acrylic.

Why?

[leethal]

Well because it would be the proper pvc compound containing conditioners and such, without the inpurities of regular plastic...

of course I could be wrong but thats what this discussion is all about, fleshing out the experiences and intuitions of others

[The Shank]

Co-extrusion is needed to get the best blank for cutting. No way to do that with a press.
At best you would get a product that would ruin your stylus after few cuts (if not at the first cut)... And forget to do that with sapphir.

[leethal]

Interesting, could you elaborate on what 'co-extrusion' is please?

[The Shank]

Google is your friend :

Coextrusion is the extrusion of multiple layers of material simultaneously. This type of extrusion utilizes two or more extruders to melt and deliver a steady volumetric throughput of different viscous plastics to a single extrusion head (die) which will extrude the materials in the desired form. This technology is used on any of the processes described above (blown film, overjacketing, tubing, sheet). The layer thicknesses are controlled by the relative speeds and sizes of the individual extruders delivering the materials.

In many real-world scenarios, a single polymer cannot meet all demands for an application. Coextrusion allows for mediation of this problem, optimizing a wide range of properties such as oxygen permeability, strength, stiffness, and wear resistance.

[leethal]

Are you saying that a single layer of pressed pvc compound will over harden/be too weak/retain oxygen/break stylis?

I would have guessed that it would be a suitable cutting medium, up til a certain date when it hardens....

I believe what you are telling me, but it seems counterintuitive. Well that answers my question about plants not making them.

[tragwag]

also keep in mind the contour of pressed blanks.
you would need a "flat" pressed blank.

[leethal]

Excellent point, I suppose a thicker plate omitting the label detent would be prudent

[opcode66]

The shape of the label area is a result of the part that holds the plate in the press. Not sure that can be eliminated....