New Project- Presto 14B / Caruso

[symatic]

some pics


the lathe in its new home




with a 12" on it for scale, 5c head attached for picture



microscope!



and a view through the microscope. 4x magnification. you can just make out there is a scale etched into the microscope lens, but its out of focus in this pic

[symatic]

So I got Impatient a while ago and ended up opening up the 5C cutting head to see inside.

It was probably my fault but one of the thin voice coil wires was broken.
I tried to solder it but ended up just damaging the coil.

It was all so dirty and messy anyway I figured it's best to replace anyway.

here's some pics so you can see the inside of the Presto 5C


In this one, the bendy bit of wire in the middle - anyone know what that is? it kinda just fell out. I dunno where its supposed to fit....

[Jccc]

Hello, that bendy wire your talking about goes on top of the magnet and it holds the magnet in place.

[symatic]

Hello, that bendy wire your talking about goes on top of the magnet and it holds the magnet in place.

ahaaaaaa


thanks man!

[symatic]

UPDATE TIME

sorry it's been so long since we updated but it all ground to a halt for a while because we had to get motor and head repairs done.

First up, Todd at Deepgrooves did an excellent job restoring our 5C head : heres his video of the process

https://www.youtube.com/watch?v=MCCCqHOI4rk&feature=youtu.be


So once that was back and our motor for the platter was fixed (it was making horrible rattling sounds) we could get on with seeing if it actually worked!

- It still turns at the wrong speed - we need to get a step-down transformer because the motors are american and we're in the uk.
- we cut some white noise with no riaa to see what happened, and we also installed a 1/2 amp fuse on the head.
- we cut some music with a very crude riaa eq on it - i just vaguely copied the graphs i could find online with fabfilter pro q. Is there any preset or anything i should use? i don't know what the best way of doing this is really.
- i think we put the stylus on backwards! we got a horrid whistling sound when we recorded music, and we had set the metal stylus up with the flat part facing forwards, and the angled part of the stylus facing the oncoming record, like it was a ship cutting through water, thats what made sense to us. we looked at manuals but even though all the diagrams said we should do it the other way, the words in the manual seemed to say we had to have the flat side facing away like that - thinking about it and looking at other manuals since, i think we cocked it up

heres a vid:

https://www.youtube.com/edit?video_id=s_E1Be7AwwI&video_referrer=watch

so next time I get a chance to play with this in a week or so i'll be trying the stylus the other way round, and also trying a polycarbonate stylus too.

i need to order some blanks from myshank.......

massive thanks to Todd for getting us off the ground, and NMCP studio in russia for advice and help!

[symatic]

we've now made a much better cut using the same setup, 5c head with a metal stylus for acetates, and we actually set the stylus the correct way round this time!

much better, but there is still some hiss, like an old 78 record or something. I don't know if this is what to expect from this equpiment though...

Could anyone advise me on the best way to set up the stylus?
are there any tools or techniques to getting the shank aligned perfectly?

also I am currently just making a crude RIAA curve using FabFilter. Are there any templates for settings to do this or should I just be looking for a bit of hardware for inverse RIAA?

We also tried a quick cut with one of MyShank's plastic dubs. we barely cut into the surface though - I think I need a heat lamp to cut those.....

[The Shank]

We also tried a quick cut with one of MyShank's plastic dubs. we barely cut into the surface though - I think I need a heat lamp to cut those.....

With a diamond stylus instead of a lamp would be a better choice IMHO.

[symatic]

We also tried a quick cut with one of MyShank's plastic dubs. we barely cut into the surface though - I think I need a heat lamp to cut those.....

With a diamond stylus instead of a lamp would be a better choice IMHO.

ah nice one man - i was gonna contact you and ask.... i'll email you

[symatic]

Hi guys

I'm looking for som advice on Motors for this beast....

we have a pair of motors that both work, one's geared for 45 and one for 33 but they are both the same spec of motor.

the problem is that thay are designed for American Power supply so even with a step-down transformer they are still turning too slow because they are receiving the wrong frequency (60Hz when it should be 50Hz)

So I've been told I need a Frequency Converter - from 50hz to 60 hz, but I have no idea what I'm looking for really! does anyone have any advice?
so far the ones I'm seeing are anywhere from £100 to £1500, and I don't know If they all do the same thing or how high spec I need.

here is a picture of our motor's specs:



It's an AC motor and here's those specs:

Volts: 115
Amps: 1.0
Duty: Cont
PH: 1
HP: 1/25
RPM: 1500/1860
Cycle: 50/60
Temperature Rise: 40°C
Type NYC-34

[markrob]

Hi,

The cheapy solution would be buy a true sine wave power inverter meant for the US market. This will take 12Vdc in (from an external power supply you provide) and output 120 Vac 60Hz. You don't need a high power unit 100 Watt is more than enough. The only issue you might run into if if the frequency of the inverter if off, then the speed will also be off. Might good to check with the manufacturer to see if they spec the accuracy.

https://www.amazon.com/dp/B00153EYX0?ref_=ams_ad_dp_asin_2

Mark

[EpicenterBryan]

So I've been told I need a Frequency Converter - from 50hz to 60 hz, but I have no idea what I'm looking for really! does anyone have any advice?

You might want to look over the last posts on this thread:
http://lathetrolls.com/viewtopic.php?f=1&t=5217&p=31447&hilit=vfd#p31447

I'm using a VFD with the same motor (NYC-34). This solution works for me, but I will be switching things over to a servo at some point.

You will need a different model than what I used because of the of the 240vac / 120vac issue... You will also want to make sure the VFD you pick is compatible with PSC & Shaded Pole Single Phase Motors.


Bryan

[symatic]

thanks mark and bryan!

will let you know how i get on

[Soulbear]

Hi Symatic,
Maybe you could check this out for your motor supply :- https://www.youtube.com/watch?v=_dgO0HdPMds This technique has been mentioned here on the Forum before I think, but the Video actually shows the U.K. Guy successfully running U.S. spec gear, here in the U.K. Hope this Helps Soulbear

[symatic]

nice one soulbear! that explains a lot.... we have the step down and the inverter, just need the power supply he has there...

I'm interested in Bryans solution too, i saw some similar products but didn't really understand what they did.

but perhaps that would be the simplest and perhaps most accurate way of doing this? the idea of being able to adjust the speed seems to be appealing. especially as half speed cutting is something we want to look at doing as a lot of the records we'll be cutting will technically be 16.66 rpm.....

[markrob]

Hi,

The VFD is the way to go because you can compensate for any small errors in the ratio of the drive system. For example, you might need to run at 59 hz instead of 60 hz to get the correct speed. Use a strobe disc to tune as needed.

Mark

[symatic]

Hi guys

finally got an update on this project:

I ended up phoning round a bunch of motor specialists and getting a new motor and a control unit that will allow me to control the speed.

the problem was that the new motor was different dimensions to the old one, there was no way round that as theres about half a century between the two motors so things have clearly changed in that time !

So we ended up going to an engineering company who made a (probably ridiculously over-specced) new bracket for us.

I gave them the original motor and its bracket so they could use it as a starting point, and to make sure it was all going to fin in the same space.

So here is a £35 motor mounted on a £300 bracket (ouch) but it looks like it'll do the job nicely. Gonna fit it next weekend and see where we are....

[markrob]

Hi,

Looks like a really nice job. Let us know how it works out. You can recoup some of the money spent by selling the NYC-34 to somebody here in the states.

Mark

[symatic]

yeah i've actually already had enquiries about the old motors!

it'll be a short while till i know if the new motor is doing the job correctly, and then I can think about it. But this Lathe is a group project so i would need to check with the rest of the team too.

One thing I forgot to add about the new Motor: they made us a nice sleeve/collar for the motor shaft as the old one was 9mm Keyed shaft and the new motor is 11mm diameter with different shape key, their solution is excellent and removable should i ever want to use the motor for somehthing else......

[symatic]

So, heres the old motor.....



and here's the new one all fitted nice with it's new bracket!



you can see the connection from the drive shaft of the motor into the mechanism for the platter is missing a screw in the pic, but its fitted now, and we just had those bits of cardboard under there to fit it, theyre out of there now. look like its a nice fit!

now we just have to figure out how to wire it up to the Invertek drive that will deliver the correct power and give us speed control

here's a pic of the whole thing as it is now.... the shelf that the motor and drive mechanism sits on has always been wonky - dunno how bad this is yet but we'l lfind out soon i hope

[Jccc]

awesome set up! Are you gonna be cutting skipless scratch records with the lathe?