R.107 tuning drive

[HMV 1120]

It hates me. And what is even more infuriating is that it was working perfectly when I received the set. The small (fine) tuning control is essential to the operation of this set, yet it has ceased to operate. Turning the small knob does absolutely nothing unless it is forcefully pushed in and rotated slowly until it 'catches', and then only at certain positions on the dial. And then it will sometimes only work in one direction.

Any pointers? I've had a look in the set but nothing has caught my eye. The tuning drive seems untouched. Are there any components that might wear out? I am wondering if the spring assembly needs replacement - although any repair would involve invasive surgery.

Yours exasperatedly, Robs.

[Sean Williams]

Rob,

It needs stripping and cleaning!

From memory it is an epicyclic drive - a small shaft, that drives three concentric ball bearings via friction, this in turn drives an outer collar, which is coupled to the tuning capacitor.....

Pull it to bits, and have a go!

Pity you arent closer, or I would have looked at it with you

Cheers
Sean

[HMV 1120]

'It needs stripping and cleaning'

I can see it now... it'll all go 'PING!'

Well, if thats what it needs... would it benefit from a very light oil? The stuff I have for a clock movement?

I'll move it to Cambridge tomorrow, then start the fun.

Regards, Robs.

[RobinBirch]

Be careful if you lubricate this. It may need greasing with a thixotropic grease such as hylomar which will give you a stiff drive when slowly rotating.

Robin

[Sean Williams]

Rob, Cambridge is a bit closer to me.....

Cheers
Sean

[RobinBirch]

Whoops, wrong gloop. The grease type is kilopoise, hylomar sticks cylinder heads on

Robin

Originally Posted by RobinBirch

Be careful if you lubricate this. It may need greasing with a thixotropic grease such as hylomar which will give you a stiff drive when slowly rotating.

Robin

[HMV 1120]

Glad to hear it Sean. So I won't be the only nutter round here then...?

The set is currently banished to the shed until I get some Emery cloth and Hammerite. According to mum I live in a bedroom and not a scrap heap. Hmm... One mans rubbish is another mans treasure...

Luckily the Radar set is quite tidy. I'll be sneaking it past customs in a few weeks ( Currently it's in devon), so I have plenty of time to get this one up to scratch.

thanks all and kind regards, Robs.

[Sean Williams]

Please, no hammerite! - it looks flipping awful!

Nice drop of olive green cellulose!

Cheers
Sean

[HMV 1120]

But hammerite is cheaper!! and it's in the garage. How about a satin coat afterwards?

[Sean Williams]

Its 'orrible - what a mean thing to do to a wonderful radio!

Seriously, if you must repaint it then do try something that looks right.

Although not rare, they arent as common as they used to be!

[HMV 1120]

Fair enough. I'll add to my list of things to buy, Money permitting. Funny thing, that list. It never seems to get shorter.

So, Cellulose paint in bright pink then?

[Skywave]

Originally Posted by Sean Williams

Please, no hammerite! - it looks flipping awful!
Nice drop of olive green cellulose!
Cheers
Sean

All a question of personal taste, Sean.

Personally, I think drab olive green looks awful & would go for grey or silver Hammerite every time. After all, grey Hammerite - or something very much like it - was good enough for Eddystone (thinks of his S888A receiver).

Al.

[Herald1360]

Originally Posted by HMV 1120

Fair enough. I'll add to my list of things to buy, Money permitting. Funny thing, that list. It never seems to get shorter.

So, Cellulose paint in bright pink then?

Only if it's luminous- it has to glow in the dark, remember?