Please note, that all advice taken on these pages is done at your own risk.  Scroll down for more articles.

Remember - always test on a part that is not on show!

Bakelite Restoration
An article by Andy Emmerson

I recently paid a visit to Gavin Payne's attractive sales outlet in the Battlesbridge Antiques Centre*, not far from Chelmsford in Essex. He has some fascinating phones for sale there, all on working demonstration, and all agreeably glossy.

We started to discuss the best way of keeping Bakelite phones black and shiny.  In Gavin's view Bakelite can easily deteriorate, especially in sunlight so the best ways of keeping the gloss are:-

  • keep the phones out of sunlight.

  • protect the surface layer (the resin that gives the gloss) by applying a coat of hard beeswax polish.

Beeswax responds well to polishing with a duster.  Silicone polishes leave a very slippery surface, so slippery in fact that you might drop your treasure when picking it up!

Afterwards I asked a friend who's an expert in chemistry what he could add and he told me the following:-

Bakelite is a cross-linked polymer of phenol and formaldehyde.  Neglecting the filler material for the moment, a Bakelite object is actually just one big molecule.  There are no polymer chain ends to be attacked so the material is quite resistant to all solvents.  But unfortunately, getting the exact proportions of the materials right is difficult. The formaldehyde boils off at lower temperatures and can be absorbed into the filler easily.

Once Bakelite has started to deteriorate you will notice a roughness of the surface, where the top layer of phenolic resin has been rubbed away, exposing the coarser filler material (wood flour or asbestos dust).  These waxes tend to fill in the surface pits and micro-cracks and make the surface look better.  But they can only slow the breakdown; they cannot stop it.

You can try and flatten this rough surface to make it smooth again; sometimes you'll be lucky.  The recommended product is automobile rubbing compound, which you can buy at car accessory shops (retail) or motor factors (trade). It's a paste the consistency of warm butter, smelling of ammonia and tan or ochre in colour.  Rub heavily with a hard cloth, then remove the residue with a clean cloth and buff with a duster.  It's certainly effective, although you'll have to rub long and hard to disguise badly pitted surfaces.

Buffing with an extremely fine abrasive can sometimes help bring back a shine.  I like to use what is called "automobile rubbing compound".  This is diatomaceous earth or fumed silica in a solvent and wax base.  It is similar to jeweller's rouge in that it is extremely fine and not exceptionally hard [the diatomaceous earth is similar to the White Cliffs of Dover, a calcium carbonate material, harder than talc. The fumed silica, however, is quite hard. Go for the softer abrasive with Bakelite.]  A buffing wheel will speed things up but watch out for the polishing to go too deep.

One collector rubs in Automobile rubbing compound (T-Cut) and then uses Liberon steel wool grade 0000, which is ultra fine and will not scratch the Bakelite.  The combination of T-Cut and steel wool gets all of the grime off and leaves the surface clean and smooth.  The second stage involves wiping the Bakelite all over with Kiwi Parade gloss black shoe polish and then buff it all off by hand using a clean cotton cloth so it leaves a nice shiny gloss finish.

You may find the Bakelite has faded badly; your options are to dye or paint.  A good black shoe polish can be quite effective to fill the minute pits; let it harden for ten minutes, then wipe off the remainder with a kitchen paper towel and buff with a duster.

There are two other automotive products you can try, with confusingly similar names-Back-to-Black and Black Bright. The former comes in an aerosol spray can and is a clear silicone varnish intended for rejuvenating black vinyl trim on cars, although being clear, it will work on other coloured surfaces as well. Black Bright is an intensely deep black (mauve-blue-black in fact) dye or liquid pigment that you 'paint' on with a felt applicator.  Because Bakelite is non-porous, it takes a while to dry (leave it for an couple of hours, then dry off the surplus with a paper towel); for a consistent finish you really do need to cover all surfaces of the telephone in order to make all the parts match. This finish benefits from a coat of polish afterwards and do take great care not to get any of the dye on your skin or clothes; it's extremely permanent!

Black shoe polish is not a perfect solution; it's basically wax and pigment. The dyes do not work on Bakelite as their solvent cannot swell the Bakelite for them to penetrate. Even though the surface may now be roughened, the Bakelite is still chemically resistant. I have sometimes found that repainting was a last resort. Unfortunately paint does not stick well to the Bakelite. You will have to roughen up the surface first to get mechanical adhesion. This is also where you do not want any silicones present so if you use silicone waxes, forget about painting.

If you use a slow-drying paint like epoxy, you can often get a good finish over fairly deep scratches. This is good as the deeper scratches will make the paint adhere more. Lacquer coatings tend to be thinner and dry fast, so the Bakelite cannot be roughened up as much. They have the advantage that a soak in solvent will remove them and allow you to repaint easily. Like everything we do in restoration, some experimentation is necessary to get things like we want.

Since Bakelite is pretty inert, silicone wax can be cleaned off by soaking in dilute sodium hydroxide (lye) for a few hours (note that the hydroxide will attack metals such as aluminium).  This will roughen the surface somewhat, but normally cleaning off silicone is preparation for painting anyway.  A silicone wax on phenolic will last longer than any other wax and give the best protection. I hesitate to suggest this to too many people since if you do get it on other surfaces (such as a painted panel) it is very difficult to remove.  One additional thing about repainting is that if the Bakelite has a fabric or cellulose filler, the paint will seal this, keeping moisture out and allowing you to retain the finish longer. I hope this helped a little. Unfortunately there are no easy fixes (and few not-so-easy ones either).

Another helpful comment I got was:

I just want to add one little bit about surface preparation before painting.  As the surface of even reasonably well preserved Bakelite contains deteriorated phenol, washing with a strong cleaner will wash away the deteriorated phenol leaving a roughened surface.  That is the first step to getting the mechanical adhesion you need.

Depending on how rough the surface is before painting, one or more coats of paint or clear coating (like polyurethane) will fill the opened pores and some rubbing down between coats will restore a smooth finish.  If using a rubbing compound before applying a clear coat be aware that all of the rubbing compound may not wash out of the pores leaving a speckled appearance.  It's better to varnish first and then polish the varnish. A swirled pattern Bakelite cabinet will thank you.

Fired with enthusiasm, I bought some rubbing compound to see what it could do.  In a nutshell, it's rather like T-Cut, with the same ammonia smell, but with a much thicker consistency.  You rub on this paste with a damp cloth, then remove the residue with a dry cloth.  It's certainly effective, although you'll have to rub long and hard to disguise badly pitted surfaces.

There must be other secret remedies for putting the gloss back into Bakelite, so if you have one, please share it with us!

*  The Old Telephone Company, in the Old Granary beside the bridge over the River Crouch, Battlesbridge. Telephone (01245-400601),  website - www.theoldtelephone.co.uk

A Collector Comments on Bakelite cleaning

The first stage is rubbing all the Bakelite with T-Cut.  Use Liberon steel wool grade 0000 (sold by Screwfix) which is ultra fine and it will not scratch the Bakelite.  The combination of T-Cut and steel wool get all of the grime off and leave the surface clean and smooth.

Clean the case with luke water water and dry off.

The second stage is to wipe the Bakelite all over with Kiwi Parade Gloss black shoe polish.  Then buff it all off by hand using a clean cotton cloth and it leaves a nice shiny gloss finish.

This is known to work and used by the editor.

Frank Goddard comments

Here is how I sometimes treat my radios.  Rub French Polish Reviver on the surface using the same polishing motion you would use to polish furniture.  Rub until the reviver does not stick and the polish surface is warm.  I use Lakeone Restorer - It works a treat


More advice from a Radio Collector

I found your information on cleaning very helpful. As for using silicon based waxes, I can get away with it on surfaces that are not badly pitted.  The product I use is Armor-All formulated for auto dashboard restoration and UV protection. The surfaces do not feel slippery after applying this product.  On badly pitted surfaces a recent new product, auto wax with colour, has given me acceptable results but may be too slick for telephone use.  A added plus of this wax is that it hides the hairline cracks that occur in bulk cast Bakelite bases on speakers and microphones.

Paste Polishing No. 5

"Paste Polishing No. 5" was used by the GPO as a general cleaner and can be used to polish up brass plugs and plastic.

It can be supplied in 60g tubes and really does do a superb job on Bakelite radios.  One tube goes a very long way.

It is still made by Greygate Chemical Products Ltd., Fir Tree Lane, Groby, Leicestershire LE6 0FH and can be obtained directly from them.

Greygate also sell a special cloth of the correct ‘hardness’ for applying the polish.  If you use a duster or an old t-shirt, you are wasting your time, as a hard (and flexible) cloth is required.  This cloth lasts a lifetime and can be washed in soapy water after polishing.  

For Paste Polishing use this link - http://www.greygate.com/product/paste-polishing-no-5/


For the special cloth see this link - http://www.greygate.com/product/application-cloth/

And of course, there is also Ebay......

How to clean Bakelite cased phones

Always test nasty substances on a part of the phone that will not be seen before using it on external surfaces.

A little bit grimy
The advice is not to do much.  Wipe over with white spirit and then buff the case.

Greasy and dirt
If there is hardly anything on the phone, just a light buffing with T-Cut will do the trick.  If only a very light buffing is required - don't shake the T-Cut bottle, just use the juice.

Once again the polish "Greygate" is recommended.

Remove transfers with warm water and glue with White spirit.

In the past Nitromors paint stripper  is effective and cannot harm Bakelite, but it can get on your skin (and up your nose, nasty fumes) and therefore relatively dangerous.

These days an overnight soak in a strong solution of biological washing liquid in water is called for.  If its a good solid paint coat, rough the surface so the detergent can get underneath.  The next morning you'll find the dirt and grease just falls off with a rinse under the tap.  Paint stains come away with a push of your fingernail (or a wooden ice lolly stick used as a spatula).  Any really stubborn lumps of paint can then be removed with (far less) Nitromors.

The overnight soak is also good for paint on ABS and Diakon cases too (but don't use Nitromors on these plastics!).

Be careful of the cradle, drawer front and knob, because they are made from cellulose acetate.  The cellulose acetate parts can be stripped by soaking them in plain warm water for a few hours and teasing the softened paint off with a fingernail.

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Last revised: February 14, 2023