The Secret Society of Lathe Trolls

Can you tell us about your screw drive motor and controller? We're in the initial stages of modifying a Scully for variable pitch.

It depends on whether your Manley transfer console is transformer coupled or not. In the past, audio electronics standards were based on telephone technology, where the input and output impedances were matched. A driving circuit with 150 ohm output impedance was supposed to be driven into a 150 ohm ...

EmAtChapterV wrote:FYou just can't send a Presto to do a Westrex's job...

Indeed. I'm still learning to make my Westrex do a Westrex's job

Out of curiosity - when someone is intentionally making a locked groove with audio (for DJ work I assume), is there a lead in to that locked groove, or do you just drop in, then remove the cutting stylus without any advance?

I'm a little puzzled by this "scaping" sound you describe. Doesn't every record have a noticeable noise at the run-out groove loop? It's such a well known record artifact, DJ's have recorded the sound into their dance mixes for years.

Also, some motor frames (which are made of laminated sheet metal) separate with age and start to hum and vibrate when AC electricity is applied to them.

Does the motor mount use rubber shock mounts? It's possible they have aged to the point where they no longer isolate vibration, but carry it on through to the frame.

I don't know about Neumann or Ortofon heads, but from my experience with Westrex 3B and 3DIIa heads, I see they cut full excursion tracks with quite minimal power input. A couple of watts is normally sufficient to drive a reasonably lively track; all that extra power in the amp rack is for the occas...

My feeling is - you can't be legally covered for anything. If they wanna nail you for throwing your toenail clippings in the recycling bin instead of the trash, they'll do it.

Unless you're a major league banker, in which case the law is whatever you say it is...

Serif, of course you're correct. We normally shoot for groove width of 2.6 to 3.0 mil, and widen it further when dealing with program material that has phase angle issues (as seen on some client projects where left and right channel have separate bass tracks - what a headache!)

Our Scully model 501 weighs about as much as 4 or 5 hipsters stacked on top of each other. But doesn't smell as bad...

We get occasional problems of chip wandering off onto the lacquer, usually it comes down to a partial blockage in one of a half dozens sections of the vacuum hose system, which lowers vacuum pressure. After ten or fifteen minutes of poking around and cleaning tubes, we find a rat's nest of chip nest...

When applying heat to the stylus on our machine, we also run the vacuum system simultaneously, so as not to allow overheating of the stylus. I have seen at least one stylus damaged from excessive heat. We use a double pole switch that engages both the heater circuit and the vacuum system when switch...

Hello, we've got a Scully 1940 era lathe (S/N 423) that may be a model 501. It's a gearbox style transmission. As shown it has a Westrex 3DIIa cutting head (using 1700 transistor electronics), but right now we're using a 3B head, which works just as well. As for pitch as marked on the panel versus r...

As for myself, I've never bootlegged anything, copied cassettes, listened to songs on the radio more than once, or driven over the speed limit. Almost all those things are illegal, don't ya know?

So - do you have the machine running? Are you cutting discs now? How's it work?

I discovered that the pilot hole spindle on our Scully lathe (which is spring loaded) presses up on discs being cut and causes the discs to not sit flat.

I use 3 looped pads of Scotch tape (about 1-2" from the spindle) to hold the disc from sliding. It is a much simpler solution than my previous attempts (including drilling the pilot hole, which got aluminum filings all over the disks).

I'm using an M-Audio Fast Track Pro. It may not be the highest of fi, but beats most of the original material I'm working with. I'm confused about some folks' claims of high LPI's with available land. At 400 LPI, the groove spacing is 2.5 mils - subtract 2 mils for groove width and there's only a ha...

That looks nice. I use an old Sears vacuum cleaner, running at 85VAC off the variac - it works just as well and didn't cost a dime. The extension hose to reach from my chip collecting bucket to the vacuum did cost a bit, but the guy at the vac supply house was able to fabricate just what I needed.