Capstan shaft sleeve 60-50Hz/transformer - UK Vintage Radio Repair and Restoration Discussion Forum

jascha · 10th Dec 2005, 7:55 pm

Hi, this is my very first post on this forum. So hello to all first of all. Very glad to see that such forums esist and there is still so much interest in these machines.

I have a tape machine from the 50s called Niccol that can be operated anywhere and has the different tappings on the transformer and the AC motor that run directly from AC runs at 100HZ. This machine has a sleeve on the capstan shaft to make the machine run at the right speed where the mains frequency is 50HZ and removed when in countries who's mains frequency is 60HZ. So far so good.

I have just purchased an identical machine, exactly the same, the only difference is that this one is made for the USA so the only difference there is is that it has a different brand name, the mains transformer has not got the different mains tappings and the capstan shaft has not got the sleeve that my other one has.

I need to have a capstan sleeve manufactured to fit this machine too, an identical sleeve to the other machine i have, the only problems i have is that the other machine is in a different country to where i am living. How can i properly calculate the different diameter of capstan shaft that i need to fit in this machine to be able for it to run at the right speed? I have an idea of what to do but i am not 100% sure it is correct:
If the current capstan shaft's diameter is x mm and i multiply by 60 and divide by 50, would that give me the right diameter i need? Is it a cae of a simple proportion with the difference in mains frequencies?

Obviously i need to have it made in the UK, although i have anoption to do it in Malta where i come from.

The other question is that the mains transformer has the following tappings:
110v primary, 100v for the ac motor, 5.5v, 5V and 6V for the valve heaters and 290v for the anode volts. Can i have this transformer rewound somewhere so i keep the same tappings but to be able to run it directly from mains voltage of 240v in this country (UK)? Is it only a case of doubling the primary windings of the transformer roughly?

Many many thanks and sorry for such a long message.
Regards

Station X · 10th Dec 2005, 8:11 pm

Hello Jascha. Welcome to the forums.

I'm not a tape recorder expert, but it seems to me that rather than have the mains transformer rewound it would be better to use an external step down transformer of suitable rating. These are sold in the UK and are fitted with UK mains plugs and US type sockets. Some of them are autotransformers, so won't provide isolation.

If a 60 Hz machine is powered from 50 Hz mains, then it will run more slowly, so a bigger capstan is needed. Measure the capstan diameter with a micrometer then multiply by 60 and divide by 50.

Making the sleeve is child's play for anyone with a lathe. The problem is that if the sleeve is made from steel it is sure to rust, so it would need to be plated in some way. Stainless steel might be better, but it's a pig to machine. I'm not sure if brass is suitable, but I expect someone else on here can advise.

Graham.

reel-to-reel-man · 10th Dec 2005, 9:09 pm

When I worked for Naples Coombe, they had a machine shop, one of the guys there made several 15ips sleeves for my Brenell's he used Brass and it caused no problems, most of the early Ferrograph also had a brass Pinch roller (The rubber was on the capstan not the pinch roller). Hope that helps

BTW nice little recorder, do you collect reel to reels?

Station X · 10th Dec 2005, 9:24 pm

Jascha.

You say in your original posting that the motor runs at 100 Hz. Is this indeed the case? If so how is the frequency doubling done?

I assume the machine in the photos is the 60 Hz version without a sleeve? What I thought was the sleeve looks far too big and I assume that I am looking at a capstan which rotates on a shaft. What holds the sleeve in place?

Graham.

jascha · 10th Dec 2005, 11:01 pm

Thanks to all who replied. Firstly i correct my mistake. It is a 100volts motor not a 100HZ. It can run at 60Hz or 50Hz no problems. As it is in the picture above is for it to run at the right speed in the USA. The picture i attached of the capstan shaft is of the capstan shaft itself that sits on top of a big flywheel. What the machine needs is a little brass sleeve that fits very tightly (slips into) onto the shaft shown in the picture. So the actual tightness of the fit is what holds the sleeve onto the shaft, but actually there is also a threaded metal head that secures everything in place but it is not shown in the picture. The sleeve will correct the speed for use in the UK and brings it up to the right speed as at the moment it runs like 20% slower.

I am already using the machine of course with a step down transformer but it would be much nicer just to connect the machine straight to a wall socket like i do with the one at home. To be able to use the machine until i sort the speed problem i record tapes using my Studer A807 and record with the varispeed reduced by 20%. Just a temporary thing of course.

It is a very nice machine and i love it (particularly the smell it emits due to its age and the valves). It has a fantastic sound . For me this particular machine has a sentimental value as the one i have in Malta i played with 32 years ago when i was just 2 years old so i love reel to reel very much. I do not really collect machines, but in my collection i have 2 Studer A807 II and a Lucor B561 (another Japanese machine made for USA). In Malta i have a Revox B77 II and the Niccol machine i mentioned which is identical to the one in the picture i attached but has black plastics instead of grey.
I used to have also a Revox A 77 (3 speed version) and also a Studer A 810 and an Ampex ATR 100. I think now i stick to the machines i have . I feel happy with them.

I also love collecting different spools and boxes. Anybody has any particular favourites?? I like the old Basf and Scotch reels and boxes with different coloured boxes. Also National Golden tape (which you can see in the attached picture). Quite a rare one!!!

Many thanks

Station X · 10th Dec 2005, 11:31 pm

You are correct in saying that to operate off UK supplies it would be necessary to double the number of turns on the primary winding. The problem with this is that the primary windings are generally the first to be put on to the core, so all the other windings have to be removed to reach them. This means there is almost as much work involved as there is in making a new transformer.

Is there room to fit a step down transformer inside the machine?

There are some transformer manufacturers listed in this post:-

https://www.vintage-radio.net/forum/...t=transformers

I'm afraid that such items are not cheap.

Graham.

10th Dec 2005, 7:55 pm	#1
jascha Hexode Join Date: Nov 2005 Location: Kent, UK. Posts: 332	Capstan shaft sleeve 60-50Hz/transformer Hi, this is my very first post on this forum. So hello to all first of all. Very glad to see that such forums esist and there is still so much interest in these machines. I have a tape machine from the 50s called Niccol that can be operated anywhere and has the different tappings on the transformer and the AC motor that run directly from AC runs at 100HZ. This machine has a sleeve on the capstan shaft to make the machine run at the right speed where the mains frequency is 50HZ and removed when in countries who's mains frequency is 60HZ. So far so good. I have just purchased an identical machine, exactly the same, the only difference is that this one is made for the USA so the only difference there is is that it has a different brand name, the mains transformer has not got the different mains tappings and the capstan shaft has not got the sleeve that my other one has. I need to have a capstan sleeve manufactured to fit this machine too, an identical sleeve to the other machine i have, the only problems i have is that the other machine is in a different country to where i am living. How can i properly calculate the different diameter of capstan shaft that i need to fit in this machine to be able for it to run at the right speed? I have an idea of what to do but i am not 100% sure it is correct: If the current capstan shaft's diameter is x mm and i multiply by 60 and divide by 50, would that give me the right diameter i need? Is it a cae of a simple proportion with the difference in mains frequencies? Obviously i need to have it made in the UK, although i have anoption to do it in Malta where i come from. The other question is that the mains transformer has the following tappings: 110v primary, 100v for the ac motor, 5.5v, 5V and 6V for the valve heaters and 290v for the anode volts. Can i have this transformer rewound somewhere so i keep the same tappings but to be able to run it directly from mains voltage of 240v in this country (UK)? Is it only a case of doubling the primary windings of the transformer roughly? Many many thanks and sorry for such a long message. Regards Attached Thumbnails

10th Dec 2005, 8:11 pm	#2
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Capstan shaft sleeve 60-50Hz/transformer Hello Jascha. Welcome to the forums. I'm not a tape recorder expert, but it seems to me that rather than have the mains transformer rewound it would be better to use an external step down transformer of suitable rating. These are sold in the UK and are fitted with UK mains plugs and US type sockets. Some of them are autotransformers, so won't provide isolation. If a 60 Hz machine is powered from 50 Hz mains, then it will run more slowly, so a bigger capstan is needed. Measure the capstan diameter with a micrometer then multiply by 60 and divide by 50. Making the sleeve is child's play for anyone with a lathe. The problem is that if the sleeve is made from steel it is sure to rust, so it would need to be plated in some way. Stainless steel might be better, but it's a pig to machine. I'm not sure if brass is suitable, but I expect someone else on here can advise. Graham.

10th Dec 2005, 9:09 pm	#3
reel-to-reel-man Heptode Join Date: Jan 2005 Location: Paignton, Devon, UK. Posts: 805	Re: Capstan shaft sleeve 60-50Hz/transformer When I worked for Naples Coombe, they had a machine shop, one of the guys there made several 15ips sleeves for my Brenell's he used Brass and it caused no problems, most of the early Ferrograph also had a brass Pinch roller (The rubber was on the capstan not the pinch roller). Hope that helps BTW nice little recorder, do you collect reel to reels? __________________ Vintage recorder collector www.vintagerecorders.co.uk

10th Dec 2005, 9:24 pm	#4
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Capstan shaft sleeve 60-50Hz/transformer Jascha. You say in your original posting that the motor runs at 100 Hz. Is this indeed the case? If so how is the frequency doubling done? I assume the machine in the photos is the 60 Hz version without a sleeve? What I thought was the sleeve looks far too big and I assume that I am looking at a capstan which rotates on a shaft. What holds the sleeve in place? Graham.

10th Dec 2005, 11:01 pm	#5
jascha Hexode Join Date: Nov 2005 Location: Kent, UK. Posts: 332	Re: Capstan shaft sleeve 60-50Hz/transformer Thanks to all who replied. Firstly i correct my mistake. It is a 100volts motor not a 100HZ. It can run at 60Hz or 50Hz no problems. As it is in the picture above is for it to run at the right speed in the USA. The picture i attached of the capstan shaft is of the capstan shaft itself that sits on top of a big flywheel. What the machine needs is a little brass sleeve that fits very tightly (slips into) onto the shaft shown in the picture. So the actual tightness of the fit is what holds the sleeve onto the shaft, but actually there is also a threaded metal head that secures everything in place but it is not shown in the picture. The sleeve will correct the speed for use in the UK and brings it up to the right speed as at the moment it runs like 20% slower. I am already using the machine of course with a step down transformer but it would be much nicer just to connect the machine straight to a wall socket like i do with the one at home. To be able to use the machine until i sort the speed problem i record tapes using my Studer A807 and record with the varispeed reduced by 20%. Just a temporary thing of course. It is a very nice machine and i love it (particularly the smell it emits due to its age and the valves). It has a fantastic sound . For me this particular machine has a sentimental value as the one i have in Malta i played with 32 years ago when i was just 2 years old so i love reel to reel very much. I do not really collect machines, but in my collection i have 2 Studer A807 II and a Lucor B561 (another Japanese machine made for USA). In Malta i have a Revox B77 II and the Niccol machine i mentioned which is identical to the one in the picture i attached but has black plastics instead of grey. I used to have also a Revox A 77 (3 speed version) and also a Studer A 810 and an Ampex ATR 100. I think now i stick to the machines i have . I feel happy with them. I also love collecting different spools and boxes. Anybody has any particular favourites?? I like the old Basf and Scotch reels and boxes with different coloured boxes. Also National Golden tape (which you can see in the attached picture). Quite a rare one!!! Many thanks Attached Thumbnails Last edited by jascha; 10th Dec 2005 at 11:13 pm.

10th Dec 2005, 11:31 pm	#6
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Capstan shaft sleeve 60-50Hz/transformer You are correct in saying that to operate off UK supplies it would be necessary to double the number of turns on the primary winding. The problem with this is that the primary windings are generally the first to be put on to the core, so all the other windings have to be removed to reach them. This means there is almost as much work involved as there is in making a new transformer. Is there room to fit a step down transformer inside the machine? There are some transformer manufacturers listed in this post:- https://www.vintage-radio.net/forum/...t=transformers I'm afraid that such items are not cheap. Graham.