The amp is an ordinary domestic hi-fi separate, 85 W per channel.

@@davidseannelson thanks for answer man I try the made this machine in the past . You know how is the minimum watts from a amp that I need to make a good emboss on polycarbonate disc? . I love this machine man congratulations 👏

@@Mirellarecords The two drivers in my cutter head are rated at 2 W continuous, but the extra headroom supplied by the 85 W amplifier is needed for short (a few ms) high-frequency peaks, such as in percussion. If the peaks are short enough the drivers will handle them without being destroyed - but it's wise to install a fuse in the line to each driver, just in case! Even the professional heads can only handle about 10 W continuous, but their amplifiers can be in the hundreds of watts.

@@davidseannelson thank you so much !!!

Yes, the motor is for use in UK, so has a shaft machined for 50 Hz mains and runs on a 240 V supply. There is an 80 V tap from the motor windings - this is not used.

@@davidseannelson Thank you I have the same Autoslim but the markings on the motor are not clear

That's right! The two drivers are wired in antiphase. The idea being that, when a mono signal is fed to them, one 'pushes' the stylus while the other 'pulls' - yielding side-to-side excursion, which is what we want. If the drivers were in phase, the recording would be vertical-cut, or 'hill-and-dale'. Such records are playable, but would need a differently wired cartridge to reproduce properly.

It depends on how far apart you want the groove windings to be... Generally I use between 70 and 110 lines/cm, depending on programme length and space available. As an example, let's take 80 lines/cm as your groove pitch. This means that the cutter head carriage has to advance by 1 mm in the time it takes the platter to rotate eight times. (Assume 1:1 gearing and a linear actuator thread pitch of 1 mm.) Then for a 33 rpm record, this would take 1.8 x 8 = 14.4 s, indicating a carriage motor speed of 4.17 rpm. For a 45 rpm record, the calculation would be 1.33 x 8 = 10.67 s, meaning that the motor would turn at 5.625 rpm.

Citation needed.

The groove pitch is set for each track on a side. Given the very limited excursion (lateral stylus movement) for embossed records, there is no real need to worry about shortage of space. I can get about 8 minutes, sometimes quite a bit more, on one side of a 7-inch 45.