|
Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment. |
|
Thread Tools |
14th Nov 2017, 4:58 pm | #1 |
Retired Dormant Member
Join Date: Nov 2017
Location: Barnstaple, Devon, UK.
Posts: 2
|
Sony HMK 70 stereo speed issues
Hi I'm trying to restore an HMK 70 Sony Stereo. I'm in need of a Thrust ball bearing for it please could anyone advise me where I can get one from or what size to search for? I'm new to all this so please have a little patience with me! I have managed to get about 2 minutes of record play before (at the same point each time) the speed drops... any advice would be appreciated. Thanks.
|
14th Nov 2017, 6:01 pm | #2 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,335
|
Re: Sony HMK 70 stereo speed issues
The fault you describe does necessarily correlate.
Before we all start making assumptions, you say you are new to all this, but do you actually mean you have stripped this all down to the point of turntable removal and the opening up of the thrust race to find just one ball bearing missing?
__________________
Edward. |
16th Nov 2017, 7:43 pm | #3 |
Heptode
Join Date: Mar 2011
Location: Dorset, UK.
Posts: 521
|
Re: Sony HMK 70 stereo speed issues
Hi,
HMK70 turntable is model TTS360. There is no separate ball bearing in the shaft bearing assembly, but an integral part of turntable shaft. Of course if the auto-stop slider steel ball bearing (4mm diameter) is missing that might cause a problem. Now a very, very common fault is for the bearing 'thrust washer' located at the base to break up. If this has happened you will notice the turntable itself is almost touching the chassis. In the past have used nothing more than a 5mm thick disc made of Delrin. You will need to remove the screw shown to allow the shaft to be released from the housing and effect repair. Rich
__________________
To an optimist a glass is half full; a pessimist half empty; an engineer twice as big as need be! |
16th Nov 2017, 8:47 pm | #4 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,853
|
Re: Sony HMK 70 stereo speed issues
I'm sure I even used a coin in a late 1970s Sony (PS1150 or similar) which had the problem Rich described.
|
18th Nov 2017, 2:24 am | #5 |
Octode
Join Date: Aug 2003
Location: Welwyn Garden City, Herts. UK.
Posts: 1,906
|
Re: Sony HMK 70 stereo speed issues
There is a piece of hard spongy rubber which deteriorates at the bottom of the bearing.
just put small washers down there to bring the turntable up to the correct height. |
18th Nov 2017, 10:08 am | #6 |
Retired Dormant Member
Join Date: Nov 2017
Location: Barnstaple, Devon, UK.
Posts: 2
|
Re: Sony HMK 70 stereo speed issues
Thanks to all. The diagram is really helpful..the thrust washer is definitely missing. I have put some small washers to bring the turntable back up to the right height. I will try and make the thrust washer but I'm running out of hope!
|
19th Nov 2017, 7:35 am | #7 |
Octode
Join Date: Aug 2003
Location: Welwyn Garden City, Herts. UK.
Posts: 1,906
|
Re: Sony HMK 70 stereo speed issues
What you have done is all you need to do
|