Automatic groove speed controller for VR

[afro7]

Someone should bundle it up with the PERFECT GROOVE software that was made free a year ago or so, that would be amazing, it would analyze and you could set the PITCH gates through your daw that directly would work on the variable DC bench supply.

I mean this isn't that big of a cake to do or?

[duomo]

Or even better with the simulathe vst because it’s easier to use in real time

[Dub Studio]

I am really excited about this thread!

BUT.... does that port only allow two options, follow the LPI pot or function at full speed?

I'm also curious about that. Is it possible to make variable pitch by using this port?

Thanks,
Bob

Yes, normally there is a jumper... pull it out and it bypasses the pot.

[Dub Studio]

Hi,

Yep! I'm not sure if the motor is expected to operate over the 100:1 or more speed range needed to run all LPI's e.g lead-in's and lead-out up to 300 lpi during cutting.

Mark

You'd be lucky... dc motors give 10:1 at best I think?

[dmills]

You can do a bit better then that given some form of encoder that can produce speed feedback to close the loop, but 100:1 would be a big ask even there.

The right answer here is a coreless BLDC with an encoder, those have a speed range mostly determined by how good your driver software is.

[mushroomjesus]

GM1 Disk Mastering Lathe Control System


or you could just buy this....

https://sawasoundengineering.com/product/gm1/

[HannesFTL]

I did some multi meter measurements on the motor voltage out while adding voltage to the shorting port, markrob is very much right on this one

When the motor is spinning freely it's just enough to do lead ins and marks

I tried using midi to cv with s-trig (shorting) to control lead in and marks only by a midi note. Worked fine for a while, but somehow my power unit died on me shortly after (maybe coincidence)

Cc to voltage is the way for total pitch control. I didn't bother as I'm mostly interested in marks, maybe future

[Dub Studio]

DC motors just aren't ideal for the range needed.

For a start, they don't work well at low rpms, so they need turn fast and be geared down, which introduces noise.

Even if you could get the ratios required, the noise coming from that thing at the highest speed would just be off the chart.

The solution that dmills describes is a much better one because the driver can sense (and therefore control) the speed of a bldc motor. This means it can work at much much lower speeds, without using gearing, and therefore won't start shaking to pieces during the lead out. The only issue is that bldc motors commonly have laminated metal cores in their stators, which will cause the motor to vibrate as the rotor magnets pass by them. The way to get around that is to use damping, or better still, coreless motors. The stators consist of just copper winding, with no laminated metal core, so there is much less vibration.

[Handcutzvinyl]

also wondering if anyone has manage to build one of these for VR .. souri doesnt seem to sell them anymore

[Thelatheofus]

https://phonolabheavyindustries.com/products/vr-t560-midi-automation-system
There is this option that looks nice

Still 2.2k and 3.5k€ is more than I would be willing to spend for something that can be built so easilly. If I managed to make something similar that works (it doesn't go as deep of course) with absolutely no knowledge on the topic I guess any lathe troll could.

Buying a 3D printer and all the parts would cost less than 400€. If you have time on your hands do it yourself.

[flozki]

if you just midi automation of the buttons of whatever lathecontroller.

i am not big fan of more knobs than needed and i dont like fancy touch screen and unnecessary displays. so my stuff is always as minimal as it can be.
same for the midi2lathe interface. well it has 4 unnecessary LEDS to show the different notes.
the optocouplers should work for

get my midi2lathe pcb here ( in trade for a nice record ,a coffee or whatever you think could be a nice trade. ) or build your own. plus arduino derivate. from 5-20.- and max 10.- for the parts.
i can provide programmed and tested: for CHF300 plus shipping. because i dont have the time to do .

its basically a arduino nano or similar and 4 optocouplers . it was made for Pitch98/13/18
its so simple you can even hand wire it.
https://github.com/flokasonaudio/pitch/blob/main/midi2lathe_pcb_preview1.png
then add a midi track in your DAW.
code. not very nice but does the job
https://github.com/flokasonaudio/pitch/blob/main/midi2lathe_0518.ino

if you want more than buttons. do a search in the lathe trolls archives. i think vienna based turntable artist Dieb13 once posted here an open source pitch controller for vinyl recorder. i think around. 2008-2010. sorry cant remember. VR is not my business and far far away.

happy cutting. f

[boryo]

if you just midi automation of the buttons of whatever lathecontroller.

i am not big fan of more knobs than needed and i dont like fancy touch screen and unnecessary displays. so my stuff is always as minimal as it can be.
same for the midi2lathe interface. well it has 4 unnecessary LEDS to show the different notes.
the optocouplers should work for

get my midi2lathe pcb here ( in trade for a nice record ,a coffee or whatever you think could be a nice trade. ) or build your own. plus arduino derivate. from 5-20.- and max 10.- for the parts.
i can provide programmed and tested: for CHF300 plus shipping. because i dont have the time to do .

its basically a arduino nano or similar and 4 optocouplers . it was made for Pitch98/13/18
its so simple you can even hand wire it.
https://github.com/flokasonaudio/pitch/blob/main/midi2lathe_pcb_preview1.png
then add a midi track in your DAW.
code. not very nice but does the job
https://github.com/flokasonaudio/pitch/blob/main/midi2lathe_0518.ino

if you want more than buttons. do a search in the lathe trolls archives. i think vienna based turntable artist Dieb13 once posted here an open source pitch controller for vinyl recorder. i think around. 2008-2010. sorry cant remember. VR is not my business and far far away.

happy cutting. f

is the chain like PC -> your device -> arduino? i dont know electronics so i wrote an entire program to play the music and send control signals to the arduino, which then controls the motor. im curious to try to make it work your way...
thanks!

[diy_cutter]

For linear movement in cutters, the best option is a servo motor. The required power is selected depending on your "trolley". In my case, it rotates the shaft on a precision Hiwin linear drive, Delta A2/B2 100W motor, torque 0.32 kg/cm, 17-bit encoder, 131072 pulses/sec. Such motors work great at low speeds, are very quiet, do not transmit vibration.

Mine is directly connected to the shaft through a coupling. It is not audible, at all. Even on the instruments.

Then you can set it up for individual buttons or program it to work in your system. Works smoothly from 0.1 rpm.

But you need to master the 400-page manual .

[Fattcamp]

Hey diy_cutter,

Where did you get that funky little red laser cross? Any time my kids are in the studio, they fiddle with things and I'm forever having to realign the overhead. I'm just been using a cardboard cutout on the platter with straight lines drawn, but a laser would be a bit more elegant (until the head blocks it's view from above at least).

Dave

[Thelatheofus]

I looked for "line laser" on amazon and got 2 separated ones that just projects a line. I 3D printed brackets to hold them so one laser highlights the diameter of my turntable's platter, and the other is aligned with the plane of my blanks. This way when I wheigh my cutterhead I can see if the stylus is aligned with both lasers : I have a scale on a platter that can go up and down, I rest a part of the cutting head on the scale, and I move that platter up or down. When I see that the stylus touches both beams I know I'm aligned on both planes (on height and depth).

It helps but I still need to re-calibrate them often. More robust metal brackts wouldn't hurt for this job. The lines of my lasers are a few mm thick so that doesn't help either, but it helps to check overall alignement.

[Fattcamp]

Nice! Thelatheofus, do you have any pics of that setup? My janky calibration method works, but it would be nice to improve for sure.

Dave

[farmersplow]

... More robust metal brackts wouldn't hurt for this job...

Attention: most cross lasers are connected to the + pole on the housing! If you mount the laser in a metal holder, you must ensure that this metal is not connected to GND (otherwise there will be a short circuit)! Only a few laser housings are insulated.
That's what happened to me.

Otherwise: Great solution for the laser and the drive!

Thomas

[diy_cutter]

Fattcamp
We bought this laser as a regular linear beam laser. It is not needed on a permanent basis and we gave it power from 18650 batteries, mounted it on a gooseneck and a magnetic base to easily use it on different machines.

Attention: most cross lasers are connected to the + pole on the housing! If you mount the laser in a metal holder, you must ensure that this metal is not connected to GND (otherwise there will be a short circuit)! Only a few laser housings are insulated.
That's what happened to me.

I completely agree with Thomas, we have several of these and only one had an insulated case.

Otherwise: Great solution for the laser and the drive!

Thank you, I hope these small improvements can make life easier for cutters and cutting machine makers.

[farmersplow]

Fattcamp
We bought this laser as a regular linear beam laser. It is not needed on a permanent basis and we gave it power from 18650 batteries, mounted it on a gooseneck and a magnetic base to easily use it on different machines.

Attention: most cross lasers are connected to the + pole on the housing! If you mount the laser in a metal holder, you must ensure that this metal is not connected to GND (otherwise there will be a short circuit)! Only a few laser housings are insulated.
That's what happened to me.

I completely agree with Thomas, we have several of these and only one had an insulated case.

Otherwise: Great solution for the laser and the drive!

Thank you, I hope these small improvements can make life easier for cutters and cutting machine makers.

I had built something similar with the cross laser back then. However, I mounted the laser on the side to set up the diamond. Here are a few pictures and a video from 2021/2022.

2021 CH-2 Laser Video.mp4

2021 CH-2 Laser Video.mp4

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2021 CH-2 Laser

2021 CH-2 Laser.jpg

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2022 Prototype one Laser 1

2022 Prototype one Laser 1.jpg

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2022 Prototype one Laser 2

2022 Prototype one Laser 2.jpg

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2023 CH-6 Laser 1

2023 CH-6 Laser 1.jpg

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2023 CH-6 Laser 2

2023 CH-6 Laser 2.jpg

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2023 CH-8 Laser 1

2023 CH-8 Laser 1.jpg

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2023 CH-8 Laser 2

2023 CH-8 Laser 2.jpg

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2023 Prototype two Laser 2

2023 Prototype two Laser 2.jpg

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Thomas