Help with speaker re-cone

Technician Join date : 2017-04-09

Back6 wrote:: Make your own cone. Measure base, cone height and size of voice coil hole. Go to https://www.blocklayer.com/cone-patternseng.aspx and make a templet using imperial measurement. Print and cut it out and glue the tab (be sure to check the tab box) with wood glue or tacky glue , let glue dry and press with clothes iron. You can purchase cone surrounds on ebay etc.

Blast from the past, answering a 6 y.o. post.

FYI

Ebay now has vendors that specialize in most of the larger, universal replacement cones in paper or foam surrounds. Cone is exponential in shape and tapers to a very tiny apex. Cut the apex to fit. For those speakers with pole piece spiders, leave 1/2" of old cone and lap joint the cone.
Always use a reversible adhesive like G-C speaker cement, the solvent is toluene. This type of cement can be used like a dry adhesive and activated with solvent very useful in pre-positioning. Shims must be used in between the voice coil and the pole piece during assembly. Blow molded plastic eyedroppers are also very useful in distributing both the glue and solvent where required.

Small cones are very hard to find but there are still vendors stocking old school small magnet speakers very inexpensive, these, with the use of solvent can salvage a cone for an even older field coil speaker re-cone.

YMMV

Chas

Guest

Make your own cone. Measure base, cone height and size of voice coil hole. Go to https://www.blocklayer.com/cone-patternseng.aspx and make a templet using imperial measurement. Print and cut it out and glue the tab (be sure to check the tab box) with wood glue or tacky glue , let glue dry and press with clothes iron. You can purchase cone surrounds on ebay etc.

Site Administrator Join date : 2010-11-22

reyesfa wrote:: Hey guys,

I've been repairing antique radios for many years.
I have always sent out the speakers for repairs.

Well, the time has come to try one myself.

My latest project is a Philco 38-62 Console.
About 40% of the cone is missing.

I have a few questions:

1) How difficult is replacing the cone?

That depends on your willingness and time to tackle that item, it can be fast and simple by replacement.

2) Where can I get one?

a- You could post ad want ad in our forum or on the web.
b- you can also cannibalize a PM speaker of the same size it looks like a 5 or 6 inch speaker and just mount the field coil and use the PM speaker,
c- or remove the pm speaker cone and glue over the left over tattered speaker.

3) There is a screw through the center of the spider, is this some kind of adjustment?

That is used to center the spider which controls speaker cone centering.

I did check for continuity of the field and voice coils. Everything seems fine with both coils.

Note you should see the schematic also shows a hum bucking coil which will have to be considered. that may be eliminated and possibly replaced by additional power supply cap.

thanks for your help,
Jose

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Beginning Member Join date : 2013-01-27

Hey guys,

I've been repairing antique radios for many years.
I have always sent out the speakers for repairs.

Well, the time has come to try one myself. Shocked

My latest project is a Philco 38-62 Console.
About 40% of the cone is missing.

I have a few questions:

1) How difficult is replacing the cone?
2) Where can I get one?
3) There is a screw thru the center of the spider, is this some kind of adjustment?

I did check for continuity of the field and voice coils. Everything seems fine with both coils.

thanks for your help,
Jose

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