How to restore metal parts in HMV 101 model? - UK Vintage Radio Repair and Restoration Discussion Forum

Roel_NLD · 12th Oct 2023, 6:52 pm

Hello,

I'm planning to rebuild my HMV 101 model entirely, as the outside and woodwork is slowly but surely falling apart. The wood work is something I'm familiar with, and I'll happily share the final design once I've reached that point. As I won't be rebuilding it 1 to 1, but change the design substantially.

As I've never restored anything with metal parts, I have no idea what is wisdom here. Nor do I know which terms I should google for, as restoration is as far as I get with my limited knowledge on the topic.

So my main question is: What are the best options to clean the shiny metal parts (speedometer, on off mechanism, shown tube of the horn?) but also what is a good way of cleaning and refurbishing the inside of the horn that is visible?

I've attached an image of the model I have, curious to any of your thoughts and suggestions.

Thanks,
Roel

Bazz4CQJ · 12th Oct 2023, 8:39 pm

Hi, welcome to the forum.

When it comes to cleaning anything you really need to know what the metal is and what the "dirt" is. Remember also, many components may be plated metal.

It's always wise to start off with the mildest cleaning agents and progress (if necessary) to more reactive ones.

In my view, any cleaning agent containing chlorides has no place in restoration work, and very many domestic cleaning products contain chlorides, often as thickening agents.

B

The Philpott · 13th Oct 2023, 1:16 pm

I believe a lot of those parts (at least those in the picture) are probably nickel plated- can anyone confirm?

If so, and if the underlying metal is brass a speckled finish is sometimes corrosion rather than dirt and it might not polish up very well, but Bazz' comments in the previous post apply regardless.

Dave

Bazz4CQJ · 13th Oct 2023, 1:32 pm

Cannot say for sure, but my first guess would also be nickel-plated brass. Some pictures at higher mags would be good.

B

stevehertz · 13th Oct 2023, 3:25 pm

Yes I agree, nickel plated.

Don't start off using 'abrasive' metal polishes, use warm water and soap/detergent to remove years of airborne grease and grime, using your finger tips and thumb to ease away the build up. Then rinse in clean water and dry thoroughly in a warm dry place or use a hair dryer. THEN, start to use a 'light' metal polish to bring back the shine. You need to avoid rubbing too hard so as not to rub through the nickel plating, easy goes it. If the nickel is rubbed away in places, personally I would leave it as it is. Getting nickel plating done is not easy and in any case the re-plated part(s) may then not match the remaining parts. best of luck.

Audio1950 · 13th Oct 2023, 9:19 pm

Quote:

Originally Posted by The Philpott

I believe a lot of those parts (at least those in the picture) are probably nickel plated- can anyone confirm?

This is a late version of the 101, having an automatic brake. As such, it may be chromium plate, rather than nickel.

Barry

Roel_NLD · 14th Oct 2023, 9:08 am

Thank you all for the input. Warm water and soap I've got!

Regarding the inside of the horn, it looks like it was coated at some point and that has kind of let go over the years. The extreme option that comes to mind is sandblasting, however not something I have in my shed... Any recommendations on this part?

And of course, once it's done I'll gladly showcase the end result. But this will be a few more months at the least!

The Philpott · 14th Oct 2023, 9:53 am

Any sort of media blasting (even gentle) will give a permanent dull pearlescent finish, so i would not consider that. If the coating must be removed, then a solvent for it needs to be found by experimentation (or by suggestion from someone who thinks they know what it is..) Pictures would be helpful.

Dave

Bazz4CQJ · 14th Oct 2023, 4:33 pm

Sandblasting is the "thermo-nuclear" level of metal cleaning in this context.
In the UK, there is a fine metal polish called Solvol Autochrome and I think a few of us on this forum have found that useful.

B

Audio1950 · 16th Oct 2023, 2:33 pm

Quote:

Originally Posted by Roel_NLD

Regarding the inside of the horn, it looks like it was coated at some point and that has kind of let go over the years. The extreme option that comes to mind is sandblasting, however not something I have in my shed... Any recommendations on this part?

I've restored quite a few internal horns over the years. The coating is very thin, and all that's needed is a rub down with fine wet and dry or emery paper, which will remove any loose or bubbling paint. Wipe over with a clean, damp cloth, and when dry, give the horn a couple of coats of black spray paint from any car accessories shop, either matt or satin finish.

Barry

Uncle Bulgaria · 17th Oct 2023, 12:08 pm

I looked into DIY nickel plating to the extent that I have some nickel bars and got an assurance from the local 'household waste recycling centre' that they would accept the resultant nickel acetate solution if clearly labelled. However, what with one thing and another I haven't actually done the plating yet.

It's possible, if you want to try your hand at returning the finish to 'very shiny' status.

stevehertz · 17th Oct 2023, 1:25 pm

Quote:

Originally Posted by Uncle Bulgaria

I looked into DIY nickel plating to the extent that I have some nickel bars and got an assurance from the local 'household waste recycling centre' that they would accept the resultant nickel acetate solution if clearly labelled. However, what with one thing and another I haven't actually done the plating yet.

It's possible, if you want to try your hand at returning the finish to 'very shiny' status.

Well, it's up to individual, and the degree of restoration that people undertake can vary from 'fixing' something to a complete restoration including paint, plating etc etc. I personally prefer to do the minimum (ha) amount of work to get the thing working and looking 'good' with a strong nod to its vintage state. Unless the item was in a basket case state, I'm not keen on glossy, 'as new' restorations.

Bazz4CQJ · 19th Oct 2023, 7:47 pm

Quote:

Originally Posted by Uncle Bulgaria

I looked into DIY nickel plating to the extent that I have some nickel bars and got an assurance from the local 'household waste recycling centre' that they would accept the resultant nickel acetate solution if clearly labelled.

Nickel plating is a funny old thing. Years ago, I worked in a lab where we used a commercial "electroless" nickel plating solution and that was "bullet proof" - plated anything and everything, but sadly, the product is long gone.

More recently, I bought some nickel plating salts on line; didn't have any success with them.

12th Oct 2023, 6:52 pm	#1
Roel_NLD Diode Join Date: Oct 2023 Location: Utrecht, Netherlands. Posts: 2	How to restore metal parts in HMV 101 model? Hello, I'm planning to rebuild my HMV 101 model entirely, as the outside and woodwork is slowly but surely falling apart. The wood work is something I'm familiar with, and I'll happily share the final design once I've reached that point. As I won't be rebuilding it 1 to 1, but change the design substantially. As I've never restored anything with metal parts, I have no idea what is wisdom here. Nor do I know which terms I should google for, as restoration is as far as I get with my limited knowledge on the topic. So my main question is: What are the best options to clean the shiny metal parts (speedometer, on off mechanism, shown tube of the horn?) but also what is a good way of cleaning and refurbishing the inside of the horn that is visible? I've attached an image of the model I have, curious to any of your thoughts and suggestions. Thanks, Roel Attached Thumbnails

12th Oct 2023, 8:39 pm	#2
Bazz4CQJ Dekatron Join Date: Apr 2009 Location: Oxfordshire, UK. Posts: 4,739	Re: How to restore metal parts in HMV 101 model? Hi, welcome to the forum. When it comes to cleaning anything you really need to know what the metal is and what the "dirt" is. Remember also, many components may be plated metal. It's always wise to start off with the mildest cleaning agents and progress (if necessary) to more reactive ones. In my view, any cleaning agent containing chlorides has no place in restoration work, and very many domestic cleaning products contain chlorides, often as thickening agents. B __________________ Saturn V had 6 million pounds of fuel. It would take thirty thousand strong men to lift it an inch.

13th Oct 2023, 1:16 pm	#3
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,023	Re: How to restore metal parts in HMV 101 model? I believe a lot of those parts (at least those in the picture) are probably nickel plated- can anyone confirm? If so, and if the underlying metal is brass a speckled finish is sometimes corrosion rather than dirt and it might not polish up very well, but Bazz' comments in the previous post apply regardless. Dave

13th Oct 2023, 1:32 pm	#4
Bazz4CQJ Dekatron Join Date: Apr 2009 Location: Oxfordshire, UK. Posts: 4,739	Re: How to restore metal parts in HMV 101 model? Cannot say for sure, but my first guess would also be nickel-plated brass. Some pictures at higher mags would be good. B __________________ Saturn V had 6 million pounds of fuel. It would take thirty thousand strong men to lift it an inch.

13th Oct 2023, 3:25 pm	#5
stevehertz Dekatron Join Date: Sep 2011 Location: Rugeley, Staffordshire, UK. Posts: 8,655	Re: How to restore metal parts in HMV 101 model? Yes I agree, nickel plated. Don't start off using 'abrasive' metal polishes, use warm water and soap/detergent to remove years of airborne grease and grime, using your finger tips and thumb to ease away the build up. Then rinse in clean water and dry thoroughly in a warm dry place or use a hair dryer. THEN, start to use a 'light' metal polish to bring back the shine. You need to avoid rubbing too hard so as not to rub through the nickel plating, easy goes it. If the nickel is rubbed away in places, personally I would leave it as it is. Getting nickel plating done is not easy and in any case the re-plated part(s) may then not match the remaining parts. best of luck. __________________ A digital radio is the latest thing, but a vintage wireless is forever..

14th Oct 2023, 9:08 am	#7
Roel_NLD Diode Join Date: Oct 2023 Location: Utrecht, Netherlands. Posts: 2	Re: How to restore metal parts in HMV 101 model? Thank you all for the input. Warm water and soap I've got! Regarding the inside of the horn, it looks like it was coated at some point and that has kind of let go over the years. The extreme option that comes to mind is sandblasting, however not something I have in my shed... Any recommendations on this part? And of course, once it's done I'll gladly showcase the end result. But this will be a few more months at the least!

14th Oct 2023, 9:53 am	#8
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,023	Re: How to restore metal parts in HMV 101 model? Any sort of media blasting (even gentle) will give a permanent dull pearlescent finish, so i would not consider that. If the coating must be removed, then a solvent for it needs to be found by experimentation (or by suggestion from someone who thinks they know what it is..) Pictures would be helpful. Dave

14th Oct 2023, 4:33 pm	#9
Bazz4CQJ Dekatron Join Date: Apr 2009 Location: Oxfordshire, UK. Posts: 4,739	Re: How to restore metal parts in HMV 101 model? Sandblasting is the "thermo-nuclear" level of metal cleaning in this context. In the UK, there is a fine metal polish called Solvol Autochrome and I think a few of us on this forum have found that useful. B __________________ Saturn V had 6 million pounds of fuel. It would take thirty thousand strong men to lift it an inch.

17th Oct 2023, 12:08 pm	#11
Uncle Bulgaria Nonode Join Date: May 2016 Location: Cornwall, UK. Posts: 2,212	Re: How to restore metal parts in HMV 101 model? I looked into DIY nickel plating to the extent that I have some nickel bars and got an assurance from the local 'household waste recycling centre' that they would accept the resultant nickel acetate solution if clearly labelled. However, what with one thing and another I haven't actually done the plating yet. It's possible, if you want to try your hand at returning the finish to 'very shiny' status.