Plans, blueprints, documentation of vintage record lathes?

[fusionkid]

Hello all,
I haven't posted here for months, I got fed up with the "go and find it yourself" responses, so i did, but this post is quite refreshing!
Been working on my own design for recording lathe with a feedback cutterhead for the past year. My aim was to make a machine able to produce usable one-off records, with a durable material, something that would stand up on a night club pa system, or just listened to at home.
For DJ's producers, enthusiasts this would be must have kit....for under £1000. I come from electro-mechanical background, it would be p**s easy to make a Neumann or Scully type lathe if the people with the answers would tell you. . . . what type of coil wire is used and why, and where to buy it, or what materials and dimensions to use to avoid resonances etc etc but they wont' because A) they spent years finding out themselves And B) they gonna use the knowledge to take peoples money £ $. So it's clearly priveleged information!
I now have all parts of my machine working although not assembled yet, the truth will be in the cut!!! i never cut a record before!!! but i have cut single revolutions, unmodulated with mock steel stylus and a diamond tip scriber - heated!! Inspected using 300XMag on kids microscope i picked up for £3. The results filled me with confidence :->
Why has everyone jumped on to lexan for disc material ?? there's other suitable types of sheet plastics available

[Aussie0zborn]

Good idea and good luck with it. I would think you would need to get hold of some cutterheads and work with an electo-mechinical genius to develop your own.

Lexan is easy to get and inexpensive. What material are you thinking of cutting on?

[fraggle]

yeah i would like to know this as well?
I was wrong when i said souri plates are poylcarbonate.
i have tested it and I don't believe this anymore.shame on me hehe
anyway i realized the cuts are pretty good with polycarbonate but more background noeise than with the souri plates. and souri plates are harder.
cheers

[fusionkid]

The vinyl recorder uses what i believe is pvc, i have used and inspected some 7" discs cut on the vinyl recorder. I believe they are pvc discs pressed in the usual way but with no recording on. I've been buying using and DJing vinyl for nearly 25 yrs so i am confident in my assesment.
Some of my tests were done on some UK 12" dance pressings, quite often on 12" singles you can find blank sides, or 1 side may be like a 10" cut on a 12" disc etc. giving you a bit to play with! I struggled to get the heat and pressure right so that it would cut at all.
So i tried a US pressed 12" hip hop, I'm not sure why but US 12" esp. hip hop the vinyl seems a lot softer, but i believe this is FOR DJs because you can bend these records slightly so that they grip the deck just right for scratching/DJing and not too tight so the deck slows, or too loose so that it spins away. This is not possible on UK pressings (in my experience) the vinyl is far more rigid. Also the soft US ones are a slighly grey looking black pvc that has slightly dull looking surface, whereas the harder UK type is very hard and with a very shiny surface.
The US one's i managed to cut with ease in fact it's a very fine balancing act trying to cut and not melt a groove in the disc. Infact i got a cheap kids microscope with 300X mag. everyone with an interest in disc cutting should get one with 300X mag. i have been inspecting many vinyl LP's etc. and it's interesting to see even major labels/ co's have discs that don't appear to be cut properly. You can clearly see either side of the groove a slightly raised bit at the top of the walls. The same effect i got when i was melting rather cutting a groove, these discs when you play them the needle often needs a nudge to get over the raised bit and into the groove.
I have a 60's 7inch that you can put the needle on the record, it will move across disc to the centre without falling in to the groove at all! But plays fine if you drop needle directly into the groove, or nudge it in.
So i think vinyl recorder discs are a pvc somewhere between the two types i have discussed, based on my research anyway! can anyone shed any light on these different types of pvc?

[dvandervort]

Hi Darren,

I've been thinking about experimenting with a PZT element head design. How hard would it be to get deflections of up to +/- .003" with a PZT element? I suspect you would have to couple the PZT to a lever of some sort to increase defection. Would this end up lowering the mechanical impedance as seen at the stylus and lower the system resonsance? As I understand, piezo positioning systems are used for very small deflections.

Mark

Hey Mark,

As for the amount of deflection, I don't think any system I have seen had just one crystal element, they were stacked to get the desired deflection. I don't think the elements I have seen were that high though. Not saying they don't exist, but a lever mechanism might be needed.

I would assume this would lower the mechanical imedance, the resonance of these crystals(in my experience) is measured in hundreds of khz so it might be OK.

Are the grooves really .003in wide? (feel free to assume I am completely ignorant of these things because I am.)

Cheers,
Darren

[markrob]

Hi Darren,

The width of the groove in not the issue. That is created by the geometry of the cutting stylus. The maximum deflection of the groove is the specification that needs to be met. I've read about stacking the elements to get more deflection and my concern is that the doing this and/or adding a lever type mechanism to increase movement would lower the resonance into the upper audio range. I think that was one of the big issues for the older crystal cutters of the 1940's and 50's. I think ideally, you would like to have the cutter be of much higher mechanical impedance in the audio range as compared to the material to be cut so that the media has little or no effect on the overall system response.

My sense is that piezo based micro-positioning systems tend to be used in applications that work at DC and low frequencies or in higher speed applications at very small defections. Is this true?

Mark

[MEGAMIKE]

piezo..
then it would be 100volt line not watts..
and from memory having 160 tin horns at a sports carnival the impedance of each amp was low..

[dvandervort]

My sense is that piezo based micro-positioning systems tend to be used in applications that work at DC and low frequencies or in higher speed applications at very small defections. Is this true?

Mark

Unless they do a type of inchworm type movement they are small deflection. What made me think of them first is they are usually used in high speed applications.

Darren

[motorino]

I know the black souri blank, and i know the black and the dark blue from harmodisk (vestax)

Are technics resines, a plastification of different resines and aditives, isnt pvc like water pipe tubes

mmm.. I've never dived inside this teme

Cheers

[fraggle]

you might be right.
I just cut the b side of a pressed record and it sounds almost the same like souri's. also the chip has the same characteristics. I would say the hardness is pretty much the same too.
I cut on a blue record made in germany.
so of course they stopped making the bloody vestax blanks yes?
cheers

[fusionkid]

Further to my last post about plastic blanks, after looking at some disks cut on a VinylRecorder machine, i have now seen two types, one like a pressed record that was 7" which from reading the latest posts i assume would be a Vestax blank and a 10" that looks to be cut from sheet plastic, presumably Souris'.
As for getting more blanks, i was looking at a sheet plastic suppliers website, the range is massive, and the plastics have a wide range of specs too. You must be able to get a suitable pvc type material off the shelf, just need to work out the required properties for your cutter. PVC would surely be better, less noisy than polycarbonate?

Also why has this thread ground to a halt?? I completely disagree that the task of building your own lathe is impossible, or that a genius is needed, i hope to demonstrate this!
What i have found is that there is minimal knowledge in the public domain, those with the knowledge (quite rightly) use it for their own personal gain. But for hobbyists and enthusiasts, this is a problem. What needs to happen is for this nut to be cracked open! So the knowledge is freely available, hobbyists like me are not going to buy Flos' cutter for $1000 or $1500 because that's not what it's about. It's about the science, knowledge and understanding. If people where more open with information i think it can only benefit the entire business. What i find annoying is that all the engineering principles employed in an recording lathe are seen all the time in other applications. If people would share some knowldege, thus avoding time and money spent on experimentation and research a lathe could definitely be built relatively cheaply. And those more serious about it could, i'm sure even make advances on the exsisting technology. The VinylRecorder for instance, is very much like the sort of thing engineering students would come up with.

[fraggle]

hey mate,
I spend hours searching for black poly and could not find it calling up companies in Germany & Australia. I called up Bayer too.
You can get in the states. I also spend hours trying to find black pvc gloss finish in 1.5mm thickness the same thing...
I can't be fu... anymore.
Vinylike is coming up with black discs soon & Cymbalism can get you some too. Not sure about PVC.
Yes you are right with the vinylrecorder.
The problem is you need time and a money!
Souri's has a workshop so he does not have to spend much.
Supply me a milling machine & Lathe & grinder and I machine you the parts. To get things machined cost a fortune where I am.
I could spend 3 monthly wages on that not included the motors just the steel parts.
If you find black PVC let me know I wanna try it too.
Cheers

[fraggle]

I don't think souri's discs are printed.
They have a protection foil.
It must be sheeting.
Look it's not a problem to get the bloody discs done.
You just have to call up a manufacturer tell him exactly what you want and they make it.
But you have to buy a lot. At least 3 tons or something like that.
Cheers

[mossboss]

Hey Man
I have a couple of lathes a milling machine a cylindrical grinder and a whole host of other engineering type gear gathering dust and a bit of rust Not the latest models but good enough to do a fairly good job
The only thing missing so as to undertake this task is a surface grinder which is no big deal any way I can get one anytime
What the fark are you doing? When are you ready to START doing it Place is full of gear and no one to use it Besides where we are the place is full of other engineering shops all willing to chip in for the hard stuff we cannot handle
So here you go say the word
Cheers

[markrob]

Also why has this thread ground to a halt?? I completely disagree that the task of building your own lathe is impossible, or that a genius is needed, i hope to demonstrate this!
What i have found is that there is minimal knowledge in the public domain, those with the knowledge (quite rightly) use it for their own personal gain. But for hobbyists and enthusiasts, this is a problem. What needs to happen is for this nut to be cracked open! So the knowledge is freely available, hobbyists like me are not going to buy Flos' cutter for $1000 or $1500 because that's not what it's about. It's about the science, knowledge and understanding. If people where more open with information i think it can only benefit the entire business. What i find annoying is that all the engineering principles employed in an recording lathe are seen all the time in other applications. If people would share some knowldege, thus avoding time and money spent on experimentation and research a lathe could definitely be built relatively cheaply. And those more serious about it could, i'm sure even make advances on the exsisting technology. The VinylRecorder for instance, is very much like the sort of thing engineering students would come up with.

Hi,

I agree with you. However, I don't think there is that much technical knowledge floating around as you might think.

The basics of moving a cutting head across a spining platter are pretty straightforward. The question is how to do it with aceptable quality on a very low budget. Being clever is the key. Using off the shelf solutions designed for this will be too costly. A new and different approach is required.

On the head design end, I suspect most, if not all of the engineers that did the work on this are long gone. There is not too much published on this subject other than patents. In my reasearch, I do have some interesting papers. The JAES Disk Recording anthology are a great start. The Maxfield and Harrison paper: "Methods of High Quality Recording and Reproducing of Music and Speech based on Telephone Reasearch" from 1926 is really good. We have to re-invent the wheel. I've done a fair amount of experimentation with decent results, but as yet, nothing I would hold out as high quality. When my work load lessens a bit, I really want to give it another shot.

Mark

[flozki]

i would say it is not easy but you can build no problem.
and i dont agree that people dont share their knowledge for their personal gain... i mean if i invest 100s of hours and lots of money to develope something it is just right that i can sell a product.
if i do it public domain then i have something else for making my living...
which is the case for me at the moment but dont expect that those few people who live from it will share all their knowlede. i am glad to see how much is shared these days. if i compare like 20 years ago this forum is paradise for someone who wants to build his own cutting lathe...

all important info is here on this forum.

if i quickly remember my older posts i think i gave you infos how to build a nice head, a good cutterhead suspension, schematics about encoder, feedback controller, motor controller. hints and tips which motors, what to use.
my disc-o-mat is completly made out of material you can order or build yourself (except the grampian. but thats just because i have it laying around and its bullet proof...
all the secrets are shared and very well explained.

so just make your own cutter....
there are a few people on this forum who are doing it or did already quite successfully.
...

and everybody is happy to see constructive input is coming back...

[emidisc]

Inspired by this site I have almost completed my diy stereo cutter head - cost approx £15
used basically hand tools as you can see!!
but not sure how to upload piccies otherwise would reveal all........