Is home-etching of vinyl records possible in any manner?

This doesn't seem practical to me. The grooves on a record are not etched or cut on the vinyl--they are cut into a lacquer disk that then has nickel electrically deposited on its surface, and this master metal disk is pressed onto the vinyl disks with 100 tons of force to make the records. http://www.youtube.com/watch?v=H342sImBY1s of how records are made. There would be nothing much left of a vinyl record after you lathed off the current recording.

I used to work with vanity presses in Nashville making custom records for various people and organizations. Actually, most cutting masters are aluminum or glass discs, with a thin coating of lacquer, which is melted/cut by the heated stylus of the cutting head of the lathe. Common sizes still in use today (and http://www.rmeinc.com/Searchresult.aspx?CategoryID=90) are 10" and 14" cutting discs, which make 45RPM and 33 & 1/3 RPM LP vinyl record finished products. Cut lacquer masters can be "played back" a limited number of times with ordinary playback phono cartridges/styli, but they are mechanically much softer than commercial vinyl pressings, and the sound fidelity degrades quickly within a few playback cycles. Cutting masters are usually sent out directly from cutting to be electroplated and perhaps duplicated into one or more production stampers, which will be the "dies" for stamping out finished two sided vinyl records. There are usually 2 cutting masters and at least 2 stampers required for each commercial record, to make the "A" and "B" sides of the record. As expensive as cutting masters may seem ($20 to $25 per master), they're cheap compared to the finished stampers, which, with their electroplating, and ancillary machine work to make them "press ready," will typically cost around $1000 per side. So, a vanity press in Nashville typically charges upwards of $5000 to make masters, stampers, and deliver a small quantity (say 1000 copies) of a vinyl LP pressing in plain paper jackets.

Ack! The first two paragraphs got switched.. if a mod could correct that it would be nifty..

[Think I fixed it, hit us at the contact form if not. ]

(FWIW, http://en.wikipedia.org/wiki/Acetate_disc, a.k.a. "dubplates," are cut directly and can be played on a record player.)

I can't speak to your specific memory, but as you already know, lathe cut records are a thing. More than that, many field recorders of the old days (1950s-1960s) used acetate cutting machines that were portable and worked in the field. The Witmark Demos by Bob Dylan are a an example of commercial demos cut directly to acetate disc rather than to tape. The big question here is whether there is enough wax on a commercial record these days to cut something else on top. I would say that except for "collector" releases (160-180g vinyl) there is not. But older, studier vinyl records I could see having enough wax to cut another groove. I have no idea whether this would actually work given the limitations of cutters and records. You might want to search YouTube for "lathe cut records." I have toyed with making a post about them, but basically, you can easily cut a playable record without too much fuss, right in your own living room. They don't sound great, but you can cut a record on a yogurt lid.

I have a similarly vague memory that might be partly imagination, but in my memory/imagination, the vinyl record is melted smooth. So I guess it would be more like casting a new black using an old record as recycled material. I'd think it would be enough of a hassle/bother that few would bother.

http://www.youtube.com/watch?v=m5Cn6wUuNqk when looking at the sidebar of some "lathe cut records" videos that OmieWise recommended.. It would appear that there was SOME manner of consumer level home record etcher.. probably an impossible find, however..

I have one of these portable lathes, somewhere--a http://www.vinylengine.com/library/rek-o-kut/turntables-and-lathes.shtml. I never managed to find blank records, but I wasn't enterprising enough to try melting a commercial release (I don't think the material is the same, so it might not even work). The sound quality I was able to achieve as an amateur engineer was...not awesome.