new guy here a few questions

[Soulbear]

Hey Fred,
Fantastic progress on your Project, and in such a short space of time, well done. Did you consider a different motor rather than the "Fixed 2-Speeds" to advance the "Overhead"?? One which you could perhaps regulate the Speed ?? The little PWM "Speed Controller" I used in my own project is not in least expensive, and the Display gives you an indicated % allowing you when needed, to quickly visually repeat any settings you make. Whilst not giving "Variable Pitch" it does however allow you to set the Cutterhead moving at "Different Speeds" allowing you to optimise the Distance "Cut" on your Recordings to both the Maximum Level and Lengths of what you're actually Recording. On a 45RPM Blank for instance, without pushing things to ridiculous extremes, I found I could vary the Time taken to fill the available "Space on the Blank" in a range between 5m:40s and 1m:47s. This Changing L.P.I. has of course an impact on the Recording Levels, and for a quite small additional outlay, it may give you many more "Recording" options on your own project.
Regards Soulbear

[fredbissnette]

so far its working out ok but i could check that out where did you get yours?

cheers

[grooveguy]

Good idea, Soulbear,

I hadn't realized that Fred's was just a 2-speed motor. I picked up a nice little gearmotor off eBay, and a board to run it. Here's the combination:

Snap3.jpg

http://www.ebay.com/itm/252213628132?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Snap2.jpg

http://www.ebay.com/itm/201425352210?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Each piece was less than US $6, postpaid directly from China in a small packet. Took about 2 weeks or less to get here. The motor is really tiny, but it has a serious step-down planetary gear drive that provides more than enough torque to drive a leadscrew or geared toothed belt. I found that with the little pot on the board, I could adjust the speed reliably anywhere between about 3 and 45 r.p.m., with good speed regulation as I grabbed the shaft to slow it down. It does NOT use the hall sensor in the motor, although there is one there. Instead it regulates speed by sensing the back-emf in the windings. I don't think this method of motor control is accurate enough to maintain a steady turntable speed, even if the motor were beefier. But for moving the carriage it ought to be just fine. My initial thought was to use this very motor to drive a leadscrew, hoping for enough speed range both to record and spiral. But the speed ratio is only about 15:1, so if I'm cutting at, say, 200 lpi, then my spiral would be only 13 lpi, not quite wide enough for a good lead-out groove. If you try to run the motor slower than the slowest setting I found, the PWM drive is evidently of such a short duty cycle that the circuit can't sense the back-emf and calculate what the drive should be, so it starts to buck. It's too bad, really, because the motor is very quiet, and could probably be mounted on the overhead, perhaps with a rubber O-ring belt to filter any torque ripple.

I have only yesterday sent away for the stepper-motor equivalent of this combination, for about twice the price. The stepper motor has 200 steps per revolution, and the controller can "micro-step" with a resolution improvement of 8X. This means that instead of 1.8-degree steps, they would be 0.225-degree ones. Again, a stretchy belt ought to smooth this out. And the stepper ought to be able to run over a 100:1 speed range. I can't wait to try this.

You know, Fred's success at a quickly-built lathe has inspired me to realize my longtime dream and build something from scratch also. Both eBay and Amazon have linear drive mechanisms intended for 3D printers, all at really good prices. Right now I'm looking for a local machinist who can turn some things on a lathe for me, something I have never mastered, beyond holding a file against something chucked-up in the drill press! There are various amateur machinist groups over here, a couple or three in my area. But most of those guys are into model railroading or small-scale steam engines, and a commercial machine shop charges the proverbial arm and leg. Help!

[fredbissnette]

im really not concerned about a lead in groove as most of the people i would make a record for would know what they are getting into and i always cut about ten seconds of non modulated grooves before and after the audio

it will always be a continuous process of improving the lathe tho so any ideas or help is greatly appreciated

shared knowledge is a good thing

cheers

[fredbissnette]

and my motor is a 1 speed geared mirror ball motor

i have two cogs on the other end of the belt to switch the speeds similar to a manual belt drive hi fi turntable does

[grooveguy]

That's great, Fred,

As long as you are happy with the lpi, and can get all of a song on a side, you're good to go. Just to satisfy my own curiosity, can you tell me how many minutes you get for every inch of music on the disc? I like to know what pitch other Trolls are recording at.

[fredbissnette]

with a 12 inch disc cutting to the standard label size i get 12:30 on my smaller gear lpi and 20:30 with my larger gear as a microgroove

so the math would be 10cm label so 4 inches minus 12/2 so 4 inches of space approx 3.2 min per inch
and at 20 per side roughly 5 min i guess

https://www.youtube.com/watch?v=dl_qZigJ0G0&feature=youtu.be
heres some cuts i made today after replacing my needle

[fredbissnette]

once i get going i plan to only cut on 10 and 7 inch discs as cdrs are a pain in the ass and track horribly towards the center

[fredbissnette]

although cdrs make a great test cut material and i will use them to make test cuts before i ruin perfectly good blanks

[fredbissnette]

i made a site for my work

http://styluspressure.my-free.website/

[grooveguy]

Good for you, Fred!

By all means, use that Website to promote your services, and to demonstrate or show-off your equipment and your work. But be sure to keep on the Lathe Trolls group as well; we are eager to know what you are up to and to share our common knowledge.

[fredbissnette]

all my technical work will be shown here on lt

cheers

[fredbissnette]

ive been thinking about needles and im aware peter king uses readily available victrola needles and im aware there are also needles available on ebay for embossing , i was thinking tungsten dart tips would be a great long lasting cutter needle for embossing

im going to try this soon

right now im using sharpened and polished nails and they work ok so far for raw needles

[CCR]

Great project, fredbissnette! What turntable did you use as a cuttable? Is it direct drive?

[grooveguy]

Hey, Fred,

I have a reprint of an article that goes into the embossing tip in some technical detail, with a conclusion that the physics of embossing has certain limitations that can't be easily overcome. Nevertheless, many Trolls here have had very good results, and I believe a lot of it has to do with the geometry of the embossing tip. Sharpening to a needle point may not be the best idea, as a radiused tip, rounded on the bottom, has much less tendency to tear material from the groove. But the tip radius and included angle of the taper needs to be fine enough that a playback stylus still rides on the groove walls and not rattle around in the bottom of the groove. Some Trolls have found success with a regular cutting stylus mounted backward, so that the angled part opposite the cutting face meets the disc material 'gently,' forcing a groove into the material without actually cutting anything. All this requires experimentation, so whatever you try, be sure to let us know of both your successes and failures.

[fredbissnette]

my turntable is a gemini xl 500 it has almost the same torque as a 1200

[Soulbear]

Hi Fred,

right now im using sharpened and polished nails and they work ok so far for raw needles

Have you thought about these for embossing??

Gramophone Needles-1.jpg

Gramophone Needles-2.jpg

At about £5/$6 for 100 they wont break the bank, and might give you even better outcomes than the pretty good results you're already getting. They're available here :-
http://www.m-p.co.uk/muk/parts/gramophone-other.htm
Regards Soulbear

[fredbissnette]

probably my next purchase

[fredbissnette]

my playback deck
this was the initial deck i used for my lathe, then when i decided to use the direct drive i had to build a deck out of this one because i had removed the arm from this one, i cut out a hole with a jig saw to mount the gemini tonearm and added a switch to manually turn on this deck plus i added some tennis balls for added feedback rejection and stability
cart is a basic audio technica diamond conical and i have 2 spare carts as well
once i got this together i painted it flat black with a brush for fun
i rip audio from my lathe cuts to my computer with this deck



the record on the deck is a serato control vinyl which i use to play digital music files off my computer using a recording interface and a basic dj program it plays files at any pitch its spinning at, funny cause now i can record digital files to discs and play them with the same deck.

[Fatrecco]

can you play your records backward/reverse by hand ? or is the needle jumping in another groove ? <-