Resharpening of cutting styli

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Maistrow
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Resharpening of cutting styli

Post: # 30669Unread post Maistrow
Thu Jul 10, 2014 8:55 pm

Hello Trolls,

Does anyone know of a service that does resharpening of cutting styli?
I received a few of the Micro Point ruby styli along with the cutting system that I
Just purchased. Is the resharpening worth doing? Does anyone know if it works?
Perhaps some time ago, this topic was mentioned on this forum.
Thanks
Maistrow

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Steve E.
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Re: Resharpening of cutting styli

Post: # 30701Unread post Steve E.
Mon Jul 14, 2014 12:44 pm

Nobody resharpens sapphires. Nobody knows how anymore. Capps used to.

Opcode66 is resharpening diamonds.

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opcode66
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Re: Resharpening of cutting styli

Post: # 30705Unread post opcode66
Mon Jul 14, 2014 5:56 pm

Modern micro-point sapphires are very hard to make. The facets are different than earlier sapphires. The facets are also different than on diamonds. Diamonds have no burnishing facets, so easier to make. See videos below.

The burnishing facet is the most difficult facet to grind. 4 microns wide. That is no joke when cutting stones. Very small. The only company I found willing to take the work mostly does contract work for the military if that tells you anything.

I think back in the day, when resharpening, they probably didn't bother with burnishing facts. I'm not exactly sure what decade burnishing facets became the norm. I'm guessing not until the advent of the micro-point stylus. If you don't worry about the burnishing facets, then sapphires are relatively easy to grind and regrind. Which is why I think it was more prevalent in the past. We read about it up to a certain time period.

I only resharpen diamonds purchased from me. Sorry. Otherwise I can't guarantee the quality of the stone or orientation of the stone's crystal lattices relative to the grinds for the facets.

Apollo can sell a sapphire for $95 only because they have the lacquer business. I hate to be the bringer of bad news here. But, I think everyone on the forum and actively cutting records absolutely needs to understand this. The sapphires you are purchasing are being subsidized by the other part of Apollo's business. It literally costs more than $95 to make these ladies and gentlemen. But, Apollo wouldn't sell many lacquers without supplying styli to cut them with.... So, that is the business model as far as I can tell. There is no confirmation other than my research into having sapphire styli made.
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Stevie342000
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Re: Resharpening of cutting styli

Post: # 30707Unread post Stevie342000
Mon Jul 14, 2014 6:37 pm

I seem to remember seeing profiles of cutting styli in some of the BBC research documents done in the 1940s I think 1944 comes to mind. You may find the BBC research papers by searching BBC Research Documents in this forum. It might tell you whether the cutting styli back then had burnishing facets, I think it is mentioned.

More information would be found in the Capps documents which can be found in the Boden book and I think online as well, probably again in this forum. Other sources with be AES documents, some are free but the main cutting ones are not they are available from AES.

The BBC documents I looked at recently I think were on surface noise in discs but from memory can not remember which one I saw it in. Burnishing facets may well not have become the norm until micro-groove recording came in in 1947 - 1949. Research may have pre-dated their actual usage per-Se.

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opcode66
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Re: Resharpening of cutting styli

Post: # 30708Unread post opcode66
Mon Jul 14, 2014 7:54 pm

Thanks for the additional information!

It is neat to see exactly how small the burnishing facet is in the video above. I have to zoom way in just to see it. To be clear, it is what we are starting to see at 0:08 in the movie.

The sapphire 3d design is accurate. It is made from precise specifications.
Cutting, Inventing & Innovating
Groove Graphics, VMS Halfnuts, MIDI Automation, Professional Stereo Feedback Cutterheads, and Pesto 1-D Cutterhead Clones
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rsimms3
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Re: Resharpening of cutting styli

Post: # 30709Unread post rsimms3
Mon Jul 14, 2014 7:58 pm

According to a patent search on Google, the first patent for a burnished facet cutting stylus was filed in 1947.

https://www.google.com/patents/US2530284?dq=burnishing+facet+stylus&hl=en&sa=X&ei=3m3EU5aVGtiiyAT3kYCYBw&ved=0CBwQ6AEwAA

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