New to record cutting, exploring possible meterials

[Radioiron]

A while back I bought an old silvertone record player and recorder (the same model actually as they use in the recording scene in The King's Speech), The radio turned out to be too much of a basket case to restore. I harvested the electronics to restore other projects and shortened the cabinet down so that it would just hold the recorder, and I overhauled the whole machine down to the rubber bushings on the recording head.
I am getting some styli and acetate disks for recording select music, but I am trying to research plastics for inexpensive, but sturdy recordings. I tried to cut a record with a handmade tool steel stylus and plexiglas sheet, but my tool is not an acceptable cutter, so I am waiting on some old stock styli.
My experiment with polycarbonate and research and reading other's experiments, I have written it off as too hard. I've been searching one of the best suppliers I can find and comparing plastic properties, and believe I have come up with some alternatives to try.
McMaster-Carr supplies sheets of plastic 12 inches square and 1/32 or 1/16 thick made of many different types.
With data on hardness and tensile strength I referenced PVC (which is too hard for the average home recorder to cut, and Cellulose acetate (which the recorders work well on). Unfortunately I can't get sheets of acetate, but comparing properties I think I've found a good substitute, HDPE has very similar tensile strength and hardness a tad on the softer side. At $3 a sheet it seems like a very good material to try.
http://www.mcmaster.com/#standard-plastic-sheets/=m0c75j
Does anyone here have any experience cutting polypropylene? I've read on here about using plastic plates, which I believe are either LDPE or HDPE, how does it cut and how is the surface noise?

[DjMikiRia]

I now have access to a Koobik Zerkoniah stone. LOL that is how I say it anyway . It does have a 45 degree angle and I counted 22 facets in the side I intend to emboss with on my homemade lathe. Factors are mounting (angle, stability). Purchased another 25 set of Sony CDRs for this experiment. Will upload results if they are worthy enough LOL. Input welcome. glass on polycarbonate http://www.youtube.com/watch?v=_5xjY9jZNms

[DjMikiRia]

cubic zirconia stylus on CDR, a jam special remix for The Secret Society of Lathe Trolls
http://kiwi6.com/file/v2plb02157 or direct mp3 link: http://k007.kiwi6.com/hotlink/v2plb02157/original_polycarbonate_jam.mp3

[chaosbc]

I never heard about glass stylus before.
Where did you bought it ? how much is it ?
Thanks

[DjMikiRia]

You see, you take a thin mirror, score it at 45 degrees of the edge. Place on counter edge, then break off LOL. That is how I get replacement glass styli.
http://kiwi6.com/file/uai94fap6v was embossed on CDR so you can not say "it does not work well". Most of my highest frequencies have resulted from using glass.

[chaosbc]

I works pretty nice ! Congratulations !
could you show us on a photo what your stylus looks like ?

[DjMikiRia]

just ordinary glass at this time, but I am willing to give "Pyrex" a try. Any kind that will keep that "syringe" sharp point.

[opcode66]

The tip of the stylus should be a 90 degree angle. Otherwise you won't get proper stereo modulation. It should match the orientation of the two coils in the cutterhead.

Also, the rough edges of your cutting stylus likely account for some of the background noise you have. Without smooth facets on the side your embossed groove wall won't be smooth thereby causing noise when played. Maybe we should send you some old sapphire styli?

[DjMikiRia]

On embossing on a CDR, I am getting some interesting results from a piece of new surgical steel razor that is actually at 45 degrees (90 to each side). The "attack" angle is about 10 degrees in direction of rotation. I will post audio results as soon as I get off work and get home.

[DjMikiRia]

Ok, I discovered after home I had nothing to emboss to LOL, so here is a "reEmboss" over a previous attempt. Pay no attention to pops and crackles as those are distortions caused by pre-existing groove. My focus on this attempt was frequency response using new surgical steel razor on a CDR:

"Chobits On ReEmbossed Polycarbonate"
http://kiwi6.com/file/9o259z5v97

Input/Feedback is always welcome

[opcode66]

Can you buy plasti picnic plates? They can be used.

[DjMikiRia]

Question: Anyone know why I am getting surface noise after changing my surgical steel razor stylus? Nothing has been altered (other than CDR brand), it is even from the same lot number of razors that until now were impressively quiet. I am increasing the angle to almost level with the disc surface (5 degrees) to see if that makes a difference.

signed,
Desperate

[Angus McCarthy]

Well, we are dealing with tolerances on the minuscule scale, here. Even if the blade came from the same stock, there's no guarantee the edge is exactly the same. Even surgical razors are not always honed with the same exactness as a purpose-cut stylus. It could very well just be the different brand of CDR - the polycarbonate mixture can vary significantly among manufacturers.

[opcode66]

She is going from a broken piece of glass to this surgical knife. So, there wasn't anything exacting about what she was using before. In fact, less so with what she was using before.

DjMikiRia: I think the issue is really with the edges. Typically, worn or chipped edges will start to make noise. So, I'm thinking the blade is not quite as fine an edge as the glass is. Also, the blade, if very thin, could be flexing at the thinnest parts and therefore vibrating and therefore adding noise.