Cutting acetate blank on T560

[808fiend]

Had a search on here about this and could not find much but have seen it mentioned and seen some cutting places offering to do it so it got me wondering

My question -

I have a blank 10" acetate that is at least 20 years old and not in the best condition (dust and very light scratches) that I was given

I am wondering if it is possible to cut on this using my vinylrecorder - bog standard with no modifications

Good idea or bad idea?

Has anyone had any luck doing this or will it result in broken stylus or other damage?

Thanks

[tragwag]

you can definitely do it! do you have just a single acetate? or do you have some scraps around for testing?
I would suggest doing a few tests to dial in the right head weight and angle for the acetate vs your usual plastic settings.

[808fiend]

you can definitely do it! do you have just a single acetate? or do you have some scraps around for testing?
I would suggest doing a few tests to dial in the right head weight and angle for the acetate vs your usual plastic settings.

Yes only got the one here unfortunately

Any tips for head weight or angle anywhere? Not even sure if it would need heating and to what temp

[boogievan]

Lacquers need a hot stylus to preclude groove hiss and to minimize the treble loss that normally occurs with decreasing disk diameter. The stylus heater wire would normally be passing around 1/2 of an Ampere of charge to make the right heat. You can dial in the correct heat by ear. Cut silence while simultaneously playing back the living groove. Crank up the phono pre (just) enough to be able to hear the hiss from the lacquer groove while the heat is still low. Gradually increase the heat while listening to the simultaneous pickup from speakers (or headphones). At some point, the hiss will get much lower than when cutting cold. Increasing the heat beyond that will produce no further reduction in remaining hiss. Dial back the heat to where the hiss noise first lowered significantly. That's your heat setting...


The vertical cutting angle needs to be whatever it needs to be in order for the pickup cart to scan well when it's designed for 15 degrees VTA. Ortofon found that the lacquer spring-back and the stylus-holder flexion, each, require 5 degrees of increased vertical cutting angle (VCA) to result in a groove that best serves a 15-degree VTA on pickup. So, they made 25 degrees VCA (= 15 + 5 + 5)...

Normally, the depth should be determined by the combination of the actual weight of the cutter (in air) plus the depth coil voltage applied that, together, make the width of the groove match what you're trying to cut. A nice width for silence in lacquer is 2,5 mils (i.e., 63.5 µm). A microscope with reticle eye piece is great for checking this...

Try cutting the non-preferred side, first - the one with the impressed serial number. That will usually have the worst evenness of the coating. Once you have the parameters sorted, flip it over and cut the intended program. ...and remember - it's Hammer Time. 'We've got to pray, just to make it today'...

[Dub Bull]

While that, all, may be true, it's not convenient to adjust a cutter's vertical tracking angle without adjusting its stylus rake angle. The Ortofon cutters that have been adapted for 25 degree VCA still have the stylus rake angle of just 1.8 degrees more 'scratching into the lacquer' than 90... The OP's cutter may not be able to make 25 degrees VCA while maintaining the nearly-orthogonal stylus orientation suitable for lacquers it why I mention it. MC Hammer in the house... (or even MM);

[Dub Studio]

Yes you can do it, the only difficulty is finding a sapphire stylus that will fit. If it’s a bit loose, stuff the gap with a tiny amount of cotton wool and it will be ok for testing.

Acetates are also thinner than vinyl dubs, so you need to adjust the weight and possibly the proximity of the stylus to the suction tube.

Apart from that, cutting acetate is practically the same. Use the same weight, and whatever heat gives you a quiet cut.

Old acetates often sound really good, just be wary of any cracks or peeling.

[Dub Studio]

Sorry for the short, late-night, phone reply... here is the long version. Cutting acetates on a T560 is possible, but not without a mod (the stylus) and some adjustments (heat and weight).

BTW old acetates do crop up quite often, and most of the time they are quite usable, so if you don't end up having much success using the one you have, you can probably find more. A couple of things to watch out for: palmitic acid, and cracking. Its normal for acetates of a certain age to start leaching palmitic acid (a greasy white substance that looks a bit like mildew) but you can probably still use them. There are detailed descriptions out there about what the acid is, and what to do about it, so I won't duplicate that here. Cracking is a serious issue caused by improper storage where a disc has been allowed to expand and contract with extremes of temperature and nothing can be done to fix this. Avoid.

Next, let's address the stylus issue. Using a T560 diamond stylus will work, but there will be a surprising amount of surface noise. This is odd considering that acetate is a relatively soft compared to what you are used to. I am not sure why this is, but I understand there are diamond styluses out there designed for use on acetate. I only cut a few acetates a week and sapphire styluses are relatively cheap and easy to get hold of, so I didn't pursue that idea any further. If you end up cutting a lot of acetates, it could be worth looking into.

If you don’t have a sapphire stylus handy, and you can put up with a little more surface noise than usual, go for it. The diamond should be OK, but be careful not to go too hot and heavy, otherwise you might penetrate the lacquer and cut into the metal substrate. I have had this happen and although the stylus did survive and I was able to remove the lump of melted aluminium from the tip, its not something I would wish to repeat. There is not much point using any heat with a diamond stylus anyway, as you won’t get rid of the surface noise no matter how much you apply.

Regarding the adjustments, I find using the same angle is fine, but you might need to adjust for the thickness of the disc and the length of the stylus. I frequently swap between diamond and sapphire, so I ensure that I have the lathe set up in such a way that it can accommodate both extremes (a long diamond stylus and a thick dub, versus a short sapphire stylus and a thin dub). It takes a bit of tweaking to avoid the stylus being too near or too far from the suction tube.

If you do get hold of a sapphire stylus, heating is crucial in order to get clean quiet cuts. The stones are generally quite short, so they can only accommodate a few turns of heating wire compared to a T560 which is much longer and can take many more turns. So whereas the T560 might need 20-30 on the dial, a sapphire could go up to as much as 50 or more before you start to hear the noise go down.

Cutting with no heat will be OK for tests, but you will probably hear a bit of crackling and hissing, so for finished work you will need to add heat until this is reduced. I do this by ear using headphones. Turn up the gain until you can hear what’s going on, and then slowly raise the temperature. The warning light will probably come on, but don’t worry, just remember to turn it back down when you swap back to diamond.

Adamant Kogyo / Namiki / Orbray styluses also have a slightly different taper on the shank which means they are not readily compatible with a T560. A fudge is to stuff a tiny whisp of cotton wool into the gap and push the shank down into it. This will usually keep it nice and snug, but if it wobbles or doesn’t go all the way in, you probably used too much.

A final word on whether this is all worth the trouble: the answer is yes. At least from my experience, acetate is a joy to work with once you get it going. Not only does it not need messy surface treatment (it works straight out of the box) the styluses are also cheaper and last for ages. But the main difference is that it is so pleasing on the ear! A lot of the criticisms that are aimed at the T560 actually relate more to the material being used than the lathe itself. Once you get the noise floor under control they are much quieter than vinyl discs, and you get a lot less distortion too, but the sound quality is so good! I love using them for my clients because the detail really comes out, but I also love cutting them for myself because they sound so sweet.