A re-coned 10" speaker from a late '20's radio has produced questionable results. Field and voice coils were intact and per spec. Radio re-capped where required, and resistors not within their stated value +/- a 20% tolerance were replaced. Although not in a cabinet as yet, the bass response is not as throaty as I remember these old radios. I fear that my rebuilt surround is not of proper compliance to produce the deeper bass I remember. The original cone had only small remnants of the original cone surround, that attached to the frame. It appeared to be shiny/wrinkled black paper, but have been unable to find anything even close. I've created a method in which to form either paper or cloth into a good reproduction of the surround, but lack the authenic material. Can anyone help?
marv

Hi Marv

The edge of the speaker can't be rigid to have good base response. Chamois (?) has been recommended for the surround.

Norm

:A re-coned 10" speaker from a late '20's radio has produced questionable results. Field and voice coils were intact and per spec. Radio re-capped where required, and resistors not within their stated value +/- a 20% tolerance were replaced. Although not in a cabinet as yet, the bass response is not as throaty as I remember these old radios. I fear that my rebuilt surround is not of proper compliance to produce the deeper bass I remember. The original cone had only small remnants of the original cone surround, that attached to the frame. It appeared to be shiny/wrinkled black paper, but have been unable to find anything even close. I've created a method in which to form either paper or cloth into a good reproduction of the surround, but lack the authenic material. Can anyone help?
:marv

Norm,
Thanks for your quick response. My first try months ago worked, but like you said it was probably too rigid or tight to duplicate the compliance of the original. I was able to create a close approximation with black Duck cloth, but wasn't quite happy with its dry shape or authenticity of appearance. I do think it would have improved the compliance and consequently, the bass response though. Just now placed a piece of semi rigid felt (gets flexible with water soak) onto my form and waiting for the oven dry. Also picked up a piece of AIDA cloth (cross stitching). Its somewhat like Duck cloth, but the weave is more coarse. The chamois sounds good if all else fails, although some black shoe dye would be needed for an authentic appearance.
marv

:Hi Marv
:
: The edge of the speaker can't be rigid to have good base response. Chamois (?) has been recommended for the surround.
:
:Norm
:
:
::A re-coned 10" speaker from a late '20's radio has produced questionable results. Field and voice coils were intact and per spec. Radio re-capped where required, and resistors not within their stated value +/- a 20% tolerance were replaced. Although not in a cabinet as yet, the bass response is not as throaty as I remember these old radios. I fear that my rebuilt surround is not of proper compliance to produce the deeper bass I remember. The original cone had only small remnants of the original cone surround, that attached to the frame. It appeared to be shiny/wrinkled black paper, but have been unable to find anything even close. I've created a method in which to form either paper or cloth into a good reproduction of the surround, but lack the authenic material. Can anyone help?
::marv

:Norm,
:Thanks for your quick response. My first try months ago worked, but like you said it was probably too rigid or tight to duplicate the compliance of the original. I was able to create a close approximation with black Duck cloth, but wasn't quite happy with its dry shape or authenticity of appearance. I do think it would have improved the compliance and consequently, the bass response though. Just now placed a piece of semi rigid felt (gets flexible with water soak) onto my form and waiting for the oven dry. Also picked up a piece of AIDA cloth (cross stitching). Its somewhat like Duck cloth, but the weave is more coarse. The chamois sounds good if all else fails, although some black shoe dye would be needed for an authentic appearance.
:marv

Apply a coat of liquid polyurethane (eg Minwax rub on) to the edge, it will provide flexibility.
:
::Hi Marv
::
:: The edge of the speaker can't be rigid to have good base response. Chamois (?) has been recommended for the surround.
::
::Norm
::
::
:::A re-coned 10" speaker from a late '20's radio has produced questionable results. Field and voice coils were intact and per spec. Radio re-capped where required, and resistors not within their stated value +/- a 20% tolerance were replaced. Although not in a cabinet as yet, the bass response is not as throaty as I remember these old radios. I fear that my rebuilt surround is not of proper compliance to produce the deeper bass I remember. The original cone had only small remnants of the original cone surround, that attached to the frame. It appeared to be shiny/wrinkled black paper, but have been unable to find anything even close. I've created a method in which to form either paper or cloth into a good reproduction of the surround, but lack the authenic material. Can anyone help?
:::marv

An addition to all that has been suggested: This is similar to Norm's Chamois. I have successfully used thin suede on both new and old speakers. I either use one piece or four pieces with the seams glued with that flexible glue they sell at sewing stores. Permatex could also be used if gray and if used discretely. I have successfully used Elmer's white glue to glue the seams, as it remains fairly flexible, and is only at four points. Making a one piece outfit is better, though, if a large piece of suede can be had. The suede is glued to the cone and frame with Elmer's. You could use super glue for faster results to the cone. To the frame you want a slow drying glue so that you can stretch the cone evenly into place (voice coil must not rub).

If you wish to rubberize cloth or suede (or chamois), many hardware stores sell long tubes (about a foot or less logn and 2-3 inches in diameter) of liquid rubberizing compound for rubberizing the ends of tool handles. It may be had in red or black. This may be soaked into felt or broadcloth or anything else you choose. Rub it into the cloth and work it out thin so that the cloth shows. Rub cloth with a rag to absorb excess. Allow to dry. You could also use Permatex gasket sealer (rubber) if black or gray can be found (usually can be). I have not worked with Permatex with this procedure, so I do not know how easy it is to rub into cloth evenly.

Also, suede is organic. If stretched properly (not super tight, but taught) it usually yields fine results, and speaker manufacturers have used this in some very old speakers. I do not know if humidity will affect speaker performance. I have not had any trouble. I assume that it would have no worse affect with suede than it would with paper.

Thomas

Norm, Nick, Thomas,
Thanks for your timely response. My best success in forming an edge surround roll has been the Duck cloth. Wetting, then placing on the form and oven drying came out nicely formed as desired. As a precaution, I liberally coated it with polyurethane spray, which unfortunately recreated the stiffness I was trying to avoid. Its mounted to the cone/frame, and looks nice (nearly authentic) I'll give it a try tomorrow, but mount the speaker assembly separately into a small enclosure to simulate a cabinet. If the response doesn't meet my expectations, I'll start by cutting slits around the circumference of the roll to relieve its stiffness. The other materials I tryed yesterday (semi rigid felt, cross stitch backing) were far to stiff, and discarded. I'll probably make 1 more attempt with the Duck cloth, but without the polyurethane coating this time. I doubt that I can form a roll with the chamois, which I believe was present on the original.
marv

:An addition to all that has been suggested: This is similar to Norm's Chamois. I have successfully used thin suede on both new and old speakers. I either use one piece or four pieces with the seams glued with that flexible glue they sell at sewing stores. Permatex could also be used if gray and if used discretely. I have successfully used Elmer's white glue to glue the seams, as it remains fairly flexible, and is only at four points. Making a one piece outfit is better, though, if a large piece of suede can be had. The suede is glued to the cone and frame with Elmer's. You could use super glue for faster results to the cone. To the frame you want a slow drying glue so that you can stretch the cone evenly into place (voice coil must not rub).
:
:If you wish to rubberize cloth or suede (or chamois), many hardware stores sell long tubes (about a foot or less logn and 2-3 inches in diameter) of liquid rubberizing compound for rubberizing the ends of tool handles. It may be had in red or black. This may be soaked into felt or broadcloth or anything else you choose. Rub it into the cloth and work it out thin so that the cloth shows. Rub cloth with a rag to absorb excess. Allow to dry. You could also use Permatex gasket sealer (rubber) if black or gray can be found (usually can be). I have not worked with Permatex with this procedure, so I do not know how easy it is to rub into cloth evenly.
:
:Also, suede is organic. If stretched properly (not super tight, but taught) it usually yields fine results, and speaker manufacturers have used this in some very old speakers. I do not know if humidity will affect speaker performance. I have not had any trouble. I assume that it would have no worse affect with suede than it would with paper.
:
:Thomas

Treat the duck cloth with rubber.

Thomas

:Norm, Nick, Thomas,
:Thanks for your timely response. My best success in forming an edge surround roll has been the Duck cloth. Wetting, then placing on the form and oven drying came out nicely formed as desired. As a precaution, I liberally coated it with polyurethane spray, which unfortunately recreated the stiffness I was trying to avoid. Its mounted to the cone/frame, and looks nice (nearly authentic) I'll give it a try tomorrow, but mount the speaker assembly separately into a small enclosure to simulate a cabinet. If the response doesn't meet my expectations, I'll start by cutting slits around the circumference of the roll to relieve its stiffness. The other materials I tryed yesterday (semi rigid felt, cross stitch backing) were far to stiff, and discarded. I'll probably make 1 more attempt with the Duck cloth, but without the polyurethane coating this time. I doubt that I can form a roll with the chamois, which I believe was present on the original.
:marv
:
::An addition to all that has been suggested: This is similar to Norm's Chamois. I have successfully used thin suede on both new and old speakers. I either use one piece or four pieces with the seams glued with that flexible glue they sell at sewing stores. Permatex could also be used if gray and if used discretely. I have successfully used Elmer's white glue to glue the seams, as it remains fairly flexible, and is only at four points. Making a one piece outfit is better, though, if a large piece of suede can be had. The suede is glued to the cone and frame with Elmer's. You could use super glue for faster results to the cone. To the frame you want a slow drying glue so that you can stretch the cone evenly into place (voice coil must not rub).
::
::If you wish to rubberize cloth or suede (or chamois), many hardware stores sell long tubes (about a foot or less logn and 2-3 inches in diameter) of liquid rubberizing compound for rubberizing the ends of tool handles. It may be had in red or black. This may be soaked into felt or broadcloth or anything else you choose. Rub it into the cloth and work it out thin so that the cloth shows. Rub cloth with a rag to absorb excess. Allow to dry. You could also use Permatex gasket sealer (rubber) if black or gray can be found (usually can be). I have not worked with Permatex with this procedure, so I do not know how easy it is to rub into cloth evenly.
::
::Also, suede is organic. If stretched properly (not super tight, but taught) it usually yields fine results, and speaker manufacturers have used this in some very old speakers. I do not know if humidity will affect speaker performance. I have not had any trouble. I assume that it would have no worse affect with suede than it would with paper.
::
::Thomas

Thomas,
Thanks Thomas. I'll search for the tool handle coating(s) you described earlier.
marv

:Treat the duck cloth with rubber.
:
:Thomas
:
::Norm, Nick, Thomas,
::Thanks for your timely response. My best success in forming an edge surround roll has been the Duck cloth. Wetting, then placing on the form and oven drying came out nicely formed as desired. As a precaution, I liberally coated it with polyurethane spray, which unfortunately recreated the stiffness I was trying to avoid. Its mounted to the cone/frame, and looks nice (nearly authentic) I'll give it a try tomorrow, but mount the speaker assembly separately into a small enclosure to simulate a cabinet. If the response doesn't meet my expectations, I'll start by cutting slits around the circumference of the roll to relieve its stiffness. The other materials I tryed yesterday (semi rigid felt, cross stitch backing) were far to stiff, and discarded. I'll probably make 1 more attempt with the Duck cloth, but without the polyurethane coating this time. I doubt that I can form a roll with the chamois, which I believe was present on the original.
::marv
::
:::An addition to all that has been suggested: This is similar to Norm's Chamois. I have successfully used thin suede on both new and old speakers. I either use one piece or four pieces with the seams glued with that flexible glue they sell at sewing stores. Permatex could also be used if gray and if used discretely. I have successfully used Elmer's white glue to glue the seams, as it remains fairly flexible, and is only at four points. Making a one piece outfit is better, though, if a large piece of suede can be had. The suede is glued to the cone and frame with Elmer's. You could use super glue for faster results to the cone. To the frame you want a slow drying glue so that you can stretch the cone evenly into place (voice coil must not rub).
:::
:::If you wish to rubberize cloth or suede (or chamois), many hardware stores sell long tubes (about a foot or less logn and 2-3 inches in diameter) of liquid rubberizing compound for rubberizing the ends of tool handles. It may be had in red or black. This may be soaked into felt or broadcloth or anything else you choose. Rub it into the cloth and work it out thin so that the cloth shows. Rub cloth with a rag to absorb excess. Allow to dry. You could also use Permatex gasket sealer (rubber) if black or gray can be found (usually can be). I have not worked with Permatex with this procedure, so I do not know how easy it is to rub into cloth evenly.
:::
:::Also, suede is organic. If stretched properly (not super tight, but taught) it usually yields fine results, and speaker manufacturers have used this in some very old speakers. I do not know if humidity will affect speaker performance. I have not had any trouble. I assume that it would have no worse affect with suede than it would with paper.
:::
:::Thomas

The results are in. The tool handle coating that I found dries too stiff on my medium weight material. I did use it over the edges of the cone attachment to seal the glue joint. A very lite paper (crepe) or fine mesh netting used with this coating, may produce a rugged compliant cone edge surround, but would be difficult to form using my method. I tried both. The last/final surround was formed as an edge roll, using Duck cloth without any further treatments/coatings. It seems to have desired flexibility and compliance. It has an authentic antique appearance, and should be at least as rugged as the original treated paper. Even though it was formed with steam, much the same way you would block a felt hat, it is equally stressed and contained around both its inner and outer perimeters, so should maintain its basic shape, even in wet climates. For those who wish to indulge themselves to this depth of speaker restoration, I have complete documentation and .jpg's available via email.
marv

:Thomas,
:Thanks Thomas. I'll search for the tool handle coating(s) you described earlier.
:marv
:
::Treat the duck cloth with rubber.
::
::Thomas
::
:::Norm, Nick, Thomas,
:::Thanks for your timely response. My best success in forming an edge surround roll has been the Duck cloth. Wetting, then placing on the form and oven drying came out nicely formed as desired. As a precaution, I liberally coated it with polyurethane spray, which unfortunately recreated the stiffness I was trying to avoid. Its mounted to the cone/frame, and looks nice (nearly authentic) I'll give it a try tomorrow, but mount the speaker assembly separately into a small enclosure to simulate a cabinet. If the response doesn't meet my expectations, I'll start by cutting slits around the circumference of the roll to relieve its stiffness. The other materials I tryed yesterday (semi rigid felt, cross stitch backing) were far to stiff, and discarded. I'll probably make 1 more attempt with the Duck cloth, but without the polyurethane coating this time. I doubt that I can form a roll with the chamois, which I believe was present on the original.
:::marv
:::
::::An addition to all that has been suggested: This is similar to Norm's Chamois. I have successfully used thin suede on both new and old speakers. I either use one piece or four pieces with the seams glued with that flexible glue they sell at sewing stores. Permatex could also be used if gray and if used discretely. I have successfully used Elmer's white glue to glue the seams, as it remains fairly flexible, and is only at four points. Making a one piece outfit is better, though, if a large piece of suede can be had. The suede is glued to the cone and frame with Elmer's. You could use super glue for faster results to the cone. To the frame you want a slow drying glue so that you can stretch the cone evenly into place (voice coil must not rub).
::::
::::If you wish to rubberize cloth or suede (or chamois), many hardware stores sell long tubes (about a foot or less logn and 2-3 inches in diameter) of liquid rubberizing compound for rubberizing the ends of tool handles. It may be had in red or black. This may be soaked into felt or broadcloth or anything else you choose. Rub it into the cloth and work it out thin so that the cloth shows. Rub cloth with a rag to absorb excess. Allow to dry. You could also use Permatex gasket sealer (rubber) if black or gray can be found (usually can be). I have not worked with Permatex with this procedure, so I do not know how easy it is to rub into cloth evenly.
::::
::::Also, suede is organic. If stretched properly (not super tight, but taught) it usually yields fine results, and speaker manufacturers have used this in some very old speakers. I do not know if humidity will affect speaker performance. I have not had any trouble. I assume that it would have no worse affect with suede than it would with paper.
::::
::::Thomas

Wow! That's pretty cool! The tool handle stuff they sell by you must not be the same as the stuff by me. Mine is in a tall white can with a colored cap (color of material). It is as rubbery as a rubber band, or perhaps more so. At any rate, your method seems to work well for you.

Thomas

Thomas,
Yep!! Same stuff. Tall white can says "Rubberize-It" It was rather hot in my garage/shop when I tried it, but can't believe that had an effect. Its rubberized plastic. Probably great for tools. Got a couple screwdrivers I use for tweaking old radios, could probably use some insulation on their metal shafts, especially when adjusting neutralizing caps. All my plastic tweakers have long since disappeared.
marv

:Wow! That's pretty cool! The tool handle stuff they sell by you must not be the same as the stuff by me. Mine is in a tall white can with a colored cap (color of material). It is as rubbery as a rubber band, or perhaps more so. At any rate, your method seems to work well for you.
:
:Thomas

Maybe they changed the formula.

T.