Speaker Surround Replacement
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    The first image is of the speaker that was in a recent acquisition, which actually did work, and has only had tubes and power cord replaced since 1929.  Considering the dates on the original capacitors, of various days in early October of 1929, this radio may actually have been a Christmas gift in someone's family:  And a grand gift it was, I am sure.  At 70 years of age, the radio is still working with the only items changed over the years  being the dial cord, most of the tubes, light bulb on the dial, and the power cord.
    Kellogg Console.
    Model Number unknown.
    Once I had the speaker removed from it's mounting location, the speaker looked like this first speaker image.  The leather surround was completely rotted away.
    Careful removal of the old material was tedious, as I scraped it off with my fingernails, while backing up the back side of the speaker cone with my thumb.
    The cement that had been used, was crystalized and brittle, so once you had a clear crisp edge to hook your fingernail, the material crumbled away.
    This picture shows the speaker ready to accept the new surround.
    The speaker's "spider", the part attached right along the top of the voice coil, which holds that part of the speaker suspended in the "basket", or frame, of the speaker; was in excellent shape, so the surround was all that was needed to be replaced.
    Your's may not come apart quite so easy.  Or if you happen to be working on a repair of a newer speaker, like rewinding and re-forming the voice coil, there are products used by picture framers which are adhesive releasing agents, which do work slowly, but quite well.  If your speaker was glued with a "spruce gum" adhesive, these may not work, as that has been the only compound that is not affected by the adhesive releasing agents.
    I did not have any leather of the same thin thickness, or softness as the original had been, BUT I had an idea- a "Chamois" of REAL chamois.  This is a suitably soft leather product, that was readily available (local auto parts store), cheap (less than 10 bucks for a 2 square foot "hide".  I did not have a nice dark background, so I simply draped it over the Kellogg speaker for this picture.
    What also ended up being the item that sent me searching for the Chamois, was this Magnavox reproducer.  (This unit has it's own power supply for the field coil, so it not an amp, nor is it just a speaker.)  This Magnavox reproducer has a surround that feels exactly like the Chamois I used.  Amazingly, the Magnavox surround is about 73 years old, and still in excellent condition.
    I used the old cardboard gasket; that was in poor shape itself; as a guide for my outline of the outer circle of the surround.  For the inner diameter, I wound up using a soup bowl as it happened to be the correct diameter to "catch" the edge of the speaker cone, which was in decent condition still, even with a few small tears at the edge.
    This picture shows the new surround trimmed, and "punched", and ready to be glued in.  The speaker also has an attaching ring that simplifies, and speeds assembly, as it is retained by screws to hold the surround in place.
    The cement I chose was "Ambroid", available at almost all hobby shops.
    Ambroid has a good track record with many of the RC airplane enthusiast's I have known, plus it proved itself on reassembling the first ever attempt I had made at reforming and rewinding a speaker voice coil- which worked out just fine.
    Ambroid also happened to have approximately the same characteristics as the old adhesive.
    The outer edge was glued in place first, and then secured with screws.  If yours is not secured with a metal ring, placing the speaker face down on a very flat surface, with the outer seal gaskets in position will work best.
    If that is not an option, you should follow the procedure for attaching the inner edge of the surround to the cone itself.
    You spread out the adhesive about 1/8 inch wide around edge of the cone,(or the full width of the basket for the alternate method of gluing the outer edge), press the gasket into the adhesive, and pull it up.  Let it dry for close to minute, then apply a second coat in the same manner as the first, and press the surround into place evenly.  You should not have any wrinkles, as the chamois is soft enough to accomodate the excess of the wrinkle.
    You may need to tend the surround for a little while as the glue takes a final set, pressing the surround down gently where needed, and "squeezing" in a little more glue in areas that absorbed the glue.
    As a final step(s)
    run a slight fillet of glue along the edge of the chamois, and repair any tears that have formed along the edge, as can be seen in the photo.
    Once dry, your speaker is ready to be placed back into service.
    With a very long wire antenna attached, there were stations found every 10KHz. Many were interfered with to the point that they were not even discernable.   On the North sloped antenna, Philadelphia came in loud and clear. as did Detroit.  New York was listenable but weak. KFAB out of Omaha was weak and distorted.  Many of the Minnesota stations west of Minneapolis filled in the gaps that  otherwise would have pulled in from states out west.   As it was, only one station in Utah on 1540KHZ, was heard. 
    E-mail me if you have a question. 

    This Antique Radio Webring site owned by John McPherson.
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