Sharp SG400E - UK Vintage Radio Repair and Restoration Discussion Forum

dsergeant · 14th Oct 2016, 10:52 am

This nice 70s radio/cassette/record deck needs new bits on its cassette deck. Belts should not be a problem, and I will change the turntable belt at the same time even though that looks OK. I see from previous posts that the pinchroller, somewhat worn, is also available (CPC AV1722 and same from ebay). The main issue is that the rubber band on the supply wheel (turntable, part 8 in the service manual) is very badly worn as is also the rewind roller (part 9) that runs against it. I have been unable to source a supply of these and suspect they are unavailable from anywhere.

Any suggestions? The unit is in good nick and it would be a shame not to be able to sort it out.

Dave

'LIVEWIRE?' · 14th Oct 2016, 1:12 pm

CPC did at one time stock tyres for idler wheels, etc. Whether they still do, or have suitable diameter tyres for the rewind & takeup spools of an SG400 I know not, but it might me worth checking their website.

camtechman · 15th Oct 2016, 6:52 am

Sometimes, especially when the rubber tyre has an indent, or worn, I turn them inside out...a bit tricky but when achieved, it works.

sp10mk11 · 15th Oct 2016, 3:02 pm

I cannot remember if the 400 tape transport uses the slim tubing on the capstan shaft to drive the take up idler/hub.
If it does it is not impossible to replace with some model aircraft silicon fuel line, though the size escaped me at present.
These are well built systems and worth getting going.
CPC can supply suitable pinch rollers for it, the one with a 2mm hole is suitable, the other is the same overall size but has a 2.5 mm hole.
Gary

sp10mk11 · 16th Oct 2016, 2:19 pm

If you can take a picture of the tape transport from the top I can see what sort of take up drive it uses
Gary

dsergeant · 17th Oct 2016, 10:58 am

Photos of deck below. After a second look I realised the black stuff on the supply reel was just rubber debris from the rewind roller. I think the main problem is just a slipping capstan belt, it had a very badly chewed cassette stuck in it.

Dave

sp10mk11 · 18th Oct 2016, 4:54 pm

This transport uses the rubber sleeve on the capstan shaft to turn the take up hub, these generally fail after some years,So when you press play, the right hand hub and pinch roller turn ok?
Gary

dsergeant · 19th Oct 2016, 11:04 am

Gary, I think you are right. Capstan belt and pinchroller replaced (CPC bits) and it is basically working but the takeup hub is jerky due to a combination of the rubber sleeve on the capstan and the play idler. Not sure what the answer is - I am sure I have a bottle of that rubber restore fluid somewhere but can't find it. It may be possible to reverse the tyre on the idler but the capstan one is not so simple.

Dave

sp10mk11 · 19th Oct 2016, 5:15 pm

For the capstan rubber you need slilcon tubing about 2mm internal diameter and about 4mm outside try a model aircraft petrol engine supplies, the old could well have turned to goo and will be a sod to clean out, but as others will tell you on here meths, acetone, brake fluid helps to clean it off.
You will need to guess the length, remove the capstan and clean all up, cut a piece to fit in the gap, then re-insert the capstan sharft so that it slides through the tubing that should be all you have to do, you might need to move the tubing up or down or a mm or two but that is basically the repair.
Gary

14th Oct 2016, 10:52 am	#1
dsergeant Octode Join Date: Mar 2006 Location: Bracknell, Berkshire,UK. Posts: 1,172	Sharp SG400E This nice 70s radio/cassette/record deck needs new bits on its cassette deck. Belts should not be a problem, and I will change the turntable belt at the same time even though that looks OK. I see from previous posts that the pinchroller, somewhat worn, is also available (CPC AV1722 and same from ebay). The main issue is that the rubber band on the supply wheel (turntable, part 8 in the service manual) is very badly worn as is also the rewind roller (part 9) that runs against it. I have been unable to source a supply of these and suspect they are unavailable from anywhere. Any suggestions? The unit is in good nick and it would be a shame not to be able to sort it out. Dave

14th Oct 2016, 1:12 pm	#2
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: Sharp SG400E CPC did at one time stock tyres for idler wheels, etc. Whether they still do, or have suitable diameter tyres for the rewind & takeup spools of an SG400 I know not, but it might me worth checking their website.

15th Oct 2016, 6:52 am	#3
camtechman Nonode Join Date: Jan 2008 Location: Milton Keynes, Bucks. UK. Posts: 2,552	Re: Sharp SG400E Sometimes, especially when the rubber tyre has an indent, or worn, I turn them inside out...a bit tricky but when achieved, it works. __________________ When I die, please don't let my Wife sell my collection for the amount I told her I paid for it!

15th Oct 2016, 3:02 pm	#4
sp10mk11 Octode Join Date: Feb 2009 Location: Cornwall, UK. Posts: 1,275	Re: Sharp SG400E I cannot remember if the 400 tape transport uses the slim tubing on the capstan shaft to drive the take up idler/hub. If it does it is not impossible to replace with some model aircraft silicon fuel line, though the size escaped me at present. These are well built systems and worth getting going. CPC can supply suitable pinch rollers for it, the one with a 2mm hole is suitable, the other is the same overall size but has a 2.5 mm hole. Gary

16th Oct 2016, 2:19 pm	#5
sp10mk11 Octode Join Date: Feb 2009 Location: Cornwall, UK. Posts: 1,275	Re: Sharp SG400E If you can take a picture of the tape transport from the top I can see what sort of take up drive it uses Gary

17th Oct 2016, 10:58 am	#6
dsergeant Octode Join Date: Mar 2006 Location: Bracknell, Berkshire,UK. Posts: 1,172	Re: Sharp SG400E Photos of deck below. After a second look I realised the black stuff on the supply reel was just rubber debris from the rewind roller. I think the main problem is just a slipping capstan belt, it had a very badly chewed cassette stuck in it. Dave Attached Thumbnails

18th Oct 2016, 4:54 pm	#7
sp10mk11 Octode Join Date: Feb 2009 Location: Cornwall, UK. Posts: 1,275	Re: Sharp SG400E This transport uses the rubber sleeve on the capstan shaft to turn the take up hub, these generally fail after some years,So when you press play, the right hand hub and pinch roller turn ok? Gary

19th Oct 2016, 11:04 am	#8
dsergeant Octode Join Date: Mar 2006 Location: Bracknell, Berkshire,UK. Posts: 1,172	Re: Sharp SG400E Gary, I think you are right. Capstan belt and pinchroller replaced (CPC bits) and it is basically working but the takeup hub is jerky due to a combination of the rubber sleeve on the capstan and the play idler. Not sure what the answer is - I am sure I have a bottle of that rubber restore fluid somewhere but can't find it. It may be possible to reverse the tyre on the idler but the capstan one is not so simple. Dave

19th Oct 2016, 5:15 pm	#9
sp10mk11 Octode Join Date: Feb 2009 Location: Cornwall, UK. Posts: 1,275	Re: Sharp SG400E For the capstan rubber you need slilcon tubing about 2mm internal diameter and about 4mm outside try a model aircraft petrol engine supplies, the old could well have turned to goo and will be a sod to clean out, but as others will tell you on here meths, acetone, brake fluid helps to clean it off. You will need to guess the length, remove the capstan and clean all up, cut a piece to fit in the gap, then re-insert the capstan sharft so that it slides through the tubing that should be all you have to do, you might need to move the tubing up or down or a mm or two but that is basically the repair. Gary