Cleaning speaker fabric - UK Vintage Radio Repair and Restoration Discussion Forum

paulsherwin · 30th Dec 2004, 11:07 am

It's notoriously difficult to clean speaker fabric, so often people leave it uncleaned. At best this results in a darkened area where the movement of the speaker has caused dust particles and fag smoke filth to accumulate on the speaker fabric.

I've discovered it's possible to clean speaker fabric using foaming cleaner (I use the bathroom cleaner from Aldi). Remove the speaker baffle, remove the speaker, and spray the outside with an even layer of foam cleaner. Leave it for about 30 seconds, then agitate it gently with a one inch paintbrush. Wipe the foam away with a damp cloth. The foam will have penetrated the fabric through the speaker hole, and a wipe with a damp rag here will remove amazing amounts of black filth. Allow the baffle and fabric to dry naturally.

I've now done this with 3 radios (all 50s) with excellent results. The fabric doesn't seem to be detached from the baffle by the detergent - the glue may be weakened, but it's still perfectly adequate. The 'black circle' is completely removed and external stains are removed or greatly reduced.

Works for me

Best regards, Paul

Sideband · 30th Dec 2004, 1:36 pm

Interesting Paul. I've tried this on a number of sets with mixed results. I think you need to use a very fine soft brush otherwise there is a danger of damaging old speaker cloth. First time I tried this on a scrap set, the old fabric was damaged by using a brush that was too hard. Anyone trying this should of course try it on something that doesn't matter first. Wonder if it works with the old Tygan fabric?

Rich.

paulsherwin · 30th Dec 2004, 2:42 pm

It's true that the speaker fabric was pretty tough on all the sets I did this to. However, if you use a soft bristle paintbrush to agitate the cleaner it shouldn't damage the fabric unless it's practically falling apart anyway. The main danger is usually that the cloth will separate from the baffle, but I found this didn't happen - sometimes the glue softened, but hardened again as everything dried out.

One advantage to cleaning cloth in this way is it removes most of the general dirt, allowing you to spot clean small stains with a cotton bud soaked in alcohol. If you do this without cleaning the fabric first, you are left with a a very obvious clean bit surrounded by dirty fabric

Best regards, Paul

Aerodyne · 30th Dec 2004, 5:52 pm

Your cleaning method sounds useful, Paul. I'll certainly give it a try. One method I've used with success in the past is as follows: (this only works when the cloth can be removed from the baffle board and is, I guess, a last-ditch attempt when all else has failed, due to the possibility of shrinkage and some shrink a lot, others hardly at all. Perhaps much depends upon the age of the fabric and whether it is a man-made thread such as Rayon or natural, such as cotton). If it won't come clean and the only option seems to be replacement, soak the cloth in luke-warm water and washing-up liquid solution to which a small amount of bleach has been added - say, no more that a few percent. Leave to soak for half an hour then remove, rinse in cold water and inspect. If it is clean, OK. If not, replace for longer. After final rinsing and drying, iron if needed with a cool iron. I have found that the small percentage of bleach does no harm to most fabrics regardless of age.
It's worth a try, failing all else.
-Tony

GMB · 31st Dec 2004, 11:15 am

Although not tried specifically on speaker fabric, a technique that I have used on other similar things is to blast them with compressed air, either through or at a glancing angle. This often removes far more dirt than wet cleaning manages and has the advantage of being entirely dry. You can crank up the pressure until things get tense and if blowing though you can support the fabric on wire mesh to stop the pressure distorting it too much.

The only disadvantage is that it is more difficult to get a uniform result as it's only the core of the jet that does the work, and it only really works for non-greasy dirt. If you have a degreasing gun then blowing air and a solvent like white spirit through will sort the greasy bits. The advantage over manual methods is that the solvent doesn't get a chance to dissolve the muck and then spread it around since it's through and gone so fast. (But do this outside as it's a terrible fire hazard!).

murphymad · 2nd Jan 2005, 11:28 pm

Hi All,

A word of Warning !

Be careful when cleaning speaker fabric whilst still attached to the baffle board.
Often on pre-war sets the baffle board will have been stained of painted black as the rest of the inside of the cabinet.
If this is the case and you get it wet, the colour will run into the material and you will end up with a stained speaker cloth, which you will wish you never started to clean.
This is certainly the case with the 1936 Murphy range...

Mike...

m didier · 3rd Jan 2005, 1:28 am

As anyone tried stardrops mixed with water. I have tried this once with very good results .Just soak the cloth in for a little while then rinse

paulsherwin · 3rd Jan 2005, 11:28 am

Quote:

Originally Posted by martin

As anyone tried stardrops mixed with water. I have tried this once with very good results .Just soak the cloth in for a little while then rinse

The problem with all methods involving removing the fabric is it's *extremely* difficult to reattach it properly. Personally I'd try all methods of cleaning 'in place' before removing the fabric for washing. Mike's point about stained baffle boards is well made though.

Best regards, Paul

Radio_Dave · 3rd Jan 2005, 4:22 pm

I think what ever method of speaker fabric washing is used there will always be great risks involved. However if the fabric is dirty and/or smelly I will always wash it without hesitation

I have found it better to try and avoid the adhesive softening. Mike has mentioned the paint from baffle boards staining but the softened adhesive can come through and stain as well. I've had this happen on a Bush VHF64 and a Ferguson 382U. Although the damage is only noticable from certain angles and it looks like a water mark.

The other problem I find when washing is that the fabric nearly always tend to shrink. I have ruined two recent radios, one an Ekco PB189 and an Ekco A23 because although the washing procedure worked well and the adhesive didn't soften, as the fabric dried and shrank it ripped apart down the centre of the speaker holes

Maybe members could start listing the radios which can safely have their speaker fabric washed and which one should not

HTH

David

30th Dec 2004, 11:07 am	#1
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,943	Cleaning speaker fabric It's notoriously difficult to clean speaker fabric, so often people leave it uncleaned. At best this results in a darkened area where the movement of the speaker has caused dust particles and fag smoke filth to accumulate on the speaker fabric. I've discovered it's possible to clean speaker fabric using foaming cleaner (I use the bathroom cleaner from Aldi). Remove the speaker baffle, remove the speaker, and spray the outside with an even layer of foam cleaner. Leave it for about 30 seconds, then agitate it gently with a one inch paintbrush. Wipe the foam away with a damp cloth. The foam will have penetrated the fabric through the speaker hole, and a wipe with a damp rag here will remove amazing amounts of black filth. Allow the baffle and fabric to dry naturally. I've now done this with 3 radios (all 50s) with excellent results. The fabric doesn't seem to be detached from the baffle by the detergent - the glue may be weakened, but it's still perfectly adequate. The 'black circle' is completely removed and external stains are removed or greatly reduced. Works for me Best regards, Paul

30th Dec 2004, 1:36 pm	#2
Sideband Dekatron Join Date: Oct 2003 Location: Croydon, Surrey, UK. Posts: 7,571	Re: Cleaning speaker fabric Interesting Paul. I've tried this on a number of sets with mixed results. I think you need to use a very fine soft brush otherwise there is a danger of damaging old speaker cloth. First time I tried this on a scrap set, the old fabric was damaged by using a brush that was too hard. Anyone trying this should of course try it on something that doesn't matter first. Wonder if it works with the old Tygan fabric? Rich.

30th Dec 2004, 2:42 pm	#3
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,943	Re: Cleaning speaker fabric It's true that the speaker fabric was pretty tough on all the sets I did this to. However, if you use a soft bristle paintbrush to agitate the cleaner it shouldn't damage the fabric unless it's practically falling apart anyway. The main danger is usually that the cloth will separate from the baffle, but I found this didn't happen - sometimes the glue softened, but hardened again as everything dried out. One advantage to cleaning cloth in this way is it removes most of the general dirt, allowing you to spot clean small stains with a cotton bud soaked in alcohol. If you do this without cleaning the fabric first, you are left with a a very obvious clean bit surrounded by dirty fabric Best regards, Paul Last edited by paulsherwin; 30th Dec 2004 at 2:50 pm.

30th Dec 2004, 5:52 pm	#4
Aerodyne Octode Join Date: Jun 2004 Location: Hampton Vale, Peterborough, UK. Posts: 1,698	Re: Cleaning speaker fabric Your cleaning method sounds useful, Paul. I'll certainly give it a try. One method I've used with success in the past is as follows: (this only works when the cloth can be removed from the baffle board and is, I guess, a last-ditch attempt when all else has failed, due to the possibility of shrinkage and some shrink a lot, others hardly at all. Perhaps much depends upon the age of the fabric and whether it is a man-made thread such as Rayon or natural, such as cotton). If it won't come clean and the only option seems to be replacement, soak the cloth in luke-warm water and washing-up liquid solution to which a small amount of bleach has been added - say, no more that a few percent. Leave to soak for half an hour then remove, rinse in cold water and inspect. If it is clean, OK. If not, replace for longer. After final rinsing and drying, iron if needed with a cool iron. I have found that the small percentage of bleach does no harm to most fabrics regardless of age. It's worth a try, failing all else. -Tony

31st Dec 2004, 11:15 am	#5
GMB Dekatron Join Date: Aug 2003 Location: near Reading (and sometimes Torquay) Posts: 3,094	Re: Cleaning speaker fabric Although not tried specifically on speaker fabric, a technique that I have used on other similar things is to blast them with compressed air, either through or at a glancing angle. This often removes far more dirt than wet cleaning manages and has the advantage of being entirely dry. You can crank up the pressure until things get tense and if blowing though you can support the fabric on wire mesh to stop the pressure distorting it too much. The only disadvantage is that it is more difficult to get a uniform result as it's only the core of the jet that does the work, and it only really works for non-greasy dirt. If you have a degreasing gun then blowing air and a solvent like white spirit through will sort the greasy bits. The advantage over manual methods is that the solvent doesn't get a chance to dissolve the muck and then spread it around since it's through and gone so fast. (But do this outside as it's a terrible fire hazard!).

2nd Jan 2005, 11:28 pm	#6
murphymad Heptode Join Date: May 2003 Location: Devizes, Wiltshire, UK. Posts: 650	Re: Cleaning speaker fabric Hi All, A word of Warning ! Be careful when cleaning speaker fabric whilst still attached to the baffle board. Often on pre-war sets the baffle board will have been stained of painted black as the rest of the inside of the cabinet. If this is the case and you get it wet, the colour will run into the material and you will end up with a stained speaker cloth, which you will wish you never started to clean. This is certainly the case with the 1936 Murphy range... Mike... __________________ Mike Barker.

3rd Jan 2005, 1:28 am	#7
m didier Retired Dormant Member Join Date: Dec 2004 Location: South Yorkshire, UK. Posts: 27	Re: Cleaning speaker fabric As anyone tried stardrops mixed with water. I have tried this once with very good results .Just soak the cloth in for a little while then rinse

3rd Jan 2005, 4:22 pm	#9
Radio_Dave Nonode Join Date: Jun 2004 Location: Norwich, Norfolk, UK. Posts: 2,543	Re: Cleaning speaker fabric I think what ever method of speaker fabric washing is used there will always be great risks involved. However if the fabric is dirty and/or smelly I will always wash it without hesitation I have found it better to try and avoid the adhesive softening. Mike has mentioned the paint from baffle boards staining but the softened adhesive can come through and stain as well. I've had this happen on a Bush VHF64 and a Ferguson 382U. Although the damage is only noticable from certain angles and it looks like a water mark. The other problem I find when washing is that the fabric nearly always tend to shrink. I have ruined two recent radios, one an Ekco PB189 and an Ekco A23 because although the washing procedure worked well and the adhesive didn't soften, as the fabric dried and shrank it ripped apart down the centre of the speaker holes Maybe members could start listing the radios which can safely have their speaker fabric washed and which one should not HTH David Last edited by Radio_Dave; 3rd Jan 2005 at 8:50 pm.