UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Television and Video

Notices

Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

Closed Thread
 
Thread Tools
Old 13th May 2022, 8:22 pm   #1
Helder Crespo
Hexode
 
Helder Crespo's Avatar
 
Join Date: Sep 2019
Location: Crystal Palace, Bromley, London, UK.
Posts: 417
Default Plating on Bush TV22 steel parts and screws?

Hi,
Does anyone know which type of plating was used for steel parts and screws in the Bush TV22 (and surely in many other TVs and radios of the same period)? The photo below shows parts from the TV22 Mk.2. Some of the parts have a yellow tint to them (they all came from a late Mk.2 scrap chassis). Now, I tend to clean parts that have excessive rust (mostly screws), usually by wire brushing and sometimes sanding, which removes the rust but also the remains of the original plating. Today I was thinking that doing this can actually be dangerous in case the screws are cadmium plated.
- Helder
Attached Thumbnails
Click image for larger version

Name:	IMG_2211.jpg
Views:	188
Size:	123.6 KB
ID:	257109  
Helder Crespo is offline  
Old 13th May 2022, 8:43 pm   #2
HamishBoxer
Dekatron
 
HamishBoxer's Avatar
 
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
Default Re: Plating on Bush TV22 steel parts and screws?

Do not think those bits are cadmium plated, unless someone knows better?
__________________
G8JET BVWS Archivist and Member V.M.A.R.S
HamishBoxer is offline  
Old 13th May 2022, 9:01 pm   #3
Freya
Octode
 
Freya's Avatar
 
Join Date: Jan 2009
Location: Falmouth, Cornwall, UK.
Posts: 1,987
Default Re: Plating on Bush TV22 steel parts and screws?

Could equally be zinc plated with a chromate element, this produces the same yellowing effect and was widely used.
__________________
Stephen
_________"It`s only an old telly" ___
Freya is offline  
Old 13th May 2022, 9:11 pm   #4
Helder Crespo
Hexode
 
Helder Crespo's Avatar
 
Join Date: Sep 2019
Location: Crystal Palace, Bromley, London, UK.
Posts: 417
Default Re: Plating on Bush TV22 steel parts and screws?

Quote:
Originally Posted by Freya View Post
Could equally be zinc plated with a chromate element, this produces the same yellowing effect and was widely used.
The yellowing seems to be oxidation, as there are parts that don't show it on the back.
Helder Crespo is offline  
Old 13th May 2022, 11:10 pm   #5
emeritus
Dekatron
 
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
Posts: 5,316
Default Re: Plating on Bush TV22 steel parts and screws?

I still have a few NOS cadmium plated bolts and their finish looks nothing like the items in the photo.
emeritus is offline  
Old 15th May 2022, 9:43 am   #6
Helder Crespo
Hexode
 
Helder Crespo's Avatar
 
Join Date: Sep 2019
Location: Crystal Palace, Bromley, London, UK.
Posts: 417
Default Re: Plating on Bush TV22 steel parts and screws?

Quote:
Originally Posted by emeritus View Post
I still have a few NOS cadmium plated bolts and their finish looks nothing like the items in the photo.
Thanks, but there also seem to be cadmium plated NOS bolts with a finish that looks very much like that on the 2BA bolts and washers in my TV22s, e.g., here:
https://www.ebay.co.uk/itm/154516616...mis&media=COPY
I guess that in practice it may be hard to distinguish old/dull zinc from old/dull cadmium. Perhaps the best way to test this (other than by X-ray spectroscopy) is by building a small "battery" with the help of some electrolyte and another metal with a well-known electrode potential - I remember reading about this somewhere (perhaps here on the forum).
- Helder
Helder Crespo is offline  
Old 15th May 2022, 9:57 am   #7
stevehertz
Dekatron
 
stevehertz's Avatar
 
Join Date: Sep 2011
Location: Rugeley, Staffordshire, UK.
Posts: 8,809
Default Re: Plating on Bush TV22 steel parts and screws?

In my Thorn Automation days the company made equipment for the admiralty and the standard finish for all chassis parts was 'cad & pass', in other words cadmium plated and passivate dip. It looked a gold/yellowish colour with a 'petrol on water' kind of rainbow effect here and there. My guess is that is what you have there. In fact now I think about it there was an album by the band Family in the early 70s called 'Bandstand' where the cover was a true photo of a Bush TV 22 front and back, it even had a 'celluloid' screen!. And on the back cover the rainbow effect on the chassis is plain to see.
__________________
A digital radio is the latest thing, but a vintage wireless is forever..
stevehertz is offline  
Old 15th May 2022, 10:17 am   #8
Helder Crespo
Hexode
 
Helder Crespo's Avatar
 
Join Date: Sep 2019
Location: Crystal Palace, Bromley, London, UK.
Posts: 417
Default Re: Plating on Bush TV22 steel parts and screws?

Quote:
Originally Posted by stevehertz View Post
In my Thorn Automation days the company made equipment for the admiralty and the standard finish for all chassis parts was 'cad & pass', in other words cadmium plated and passivate dip. It looked a gold/yellowish colour with a 'petrol on water' kind of rainbow effect here and there. My guess is that is what you have there. In fact now I think about it there was an album by the band Family in the early 70s called 'Bandstand' where the cover was a true photo of a Bush TV 22 front and back, it even had a 'celluloid' screen!. And on the back cover the rainbow effect on the chassis is plain to see.
Thanks, but I think the effect seen in the album photo is mostly due to colour grading / artistic liberty from the sleeve designers, as it is mostly noticeable in the chassis itself but the chassis is plain aluminium in all TV22 vintages/models.
- Helder
Attached Thumbnails
Click image for larger version

Name:	21849074074_fdddd9bd2d_h.jpg
Views:	84
Size:	81.8 KB
ID:	257192  
Helder Crespo is offline  
Old 15th May 2022, 10:20 am   #9
Heatercathodeshort
Dekatron
 
Heatercathodeshort's Avatar
 
Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 9,145
Default Re: Plating on Bush TV22 steel parts and screws?

The finish code for EMI 1937. Bush probably used the least expensive bolts just for light assembly. J.
Attached Thumbnails
Click image for larger version

Name:	Finish.jpg
Views:	96
Size:	86.5 KB
ID:	257193  
Heatercathodeshort is offline  
Old 15th May 2022, 10:32 am   #10
Helder Crespo
Hexode
 
Helder Crespo's Avatar
 
Join Date: Sep 2019
Location: Crystal Palace, Bromley, London, UK.
Posts: 417
Default Re: Plating on Bush TV22 steel parts and screws?

Quote:
Originally Posted by Heatercathodeshort View Post
The finish code for EMI 1937. Bush probably used the least expensive bolts just for light assembly. J.
Thanks John. So most parts are plain, others WN, and only a couple of them C&P (quite possibly the cadmium + passivate dip mentioned by stevehertz); there are also some Red xyz. Any idea on what WN means? Something nickel perhaps?
- Helder

p.s. - Just noticed the finishing codes below...

Last edited by Helder Crespo; 15th May 2022 at 10:34 am. Reason: added p.s.
Helder Crespo is offline  
Old 16th May 2022, 9:31 pm   #11
peter_scott
Dekatron
 
peter_scott's Avatar
 
Join Date: May 2003
Location: Edinburgh, UK.
Posts: 3,273
Default Re: Plating on Bush TV22 steel parts and screws?

Hi Helder,

Thanks to Jac Janssen we do have the complete set of EMI finishes.

Oops, John got there first.

Peter
Attached Thumbnails
Click image for larger version

Name:	EMI finish codes.jpg
Views:	69
Size:	30.0 KB
ID:	257303  
peter_scott is offline  
Old 16th May 2022, 10:23 pm   #12
Helder Crespo
Hexode
 
Helder Crespo's Avatar
 
Join Date: Sep 2019
Location: Crystal Palace, Bromley, London, UK.
Posts: 417
Default Re: Plating on Bush TV22 steel parts and screws?

Quote:
Originally Posted by peter_scott View Post
Hi Helder,

Thanks to Jac Janssen we do have the complete set of EMI finishes.

Oops, John got there first.

Peter
Thanks Peter!
This is even more comprehensive than John's table. Is Bush/Rank supposed to have followed EMI's finishes? If so, then i believe the most likely finish for the parts I mentioned is White Nickel.
- Helder
Helder Crespo is offline  
Old 17th May 2022, 6:43 pm   #13
Heatercathodeshort
Dekatron
 
Heatercathodeshort's Avatar
 
Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 9,145
Default Re: Plating on Bush TV22 steel parts and screws?

EMI were crazy with their over the top detail for something that was obsolete after 10 years. It probably had a lot to do with their collapse of domestic radio and TV production. J.
Heatercathodeshort is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 11:12 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.