Sorry for sounding clueless here...but I have a 1947 Philco 48-250 that was restored "professionally" in 2001. After closer inspection, it appears that the speaker was repaired with a clear silicone. Well, that didn't last. The speaker crackles like it is falling apart. If I very lightly push the speaker material at the top, it gets clear as a bell. Is there a way to fix this, or should I get a replacement for the speaker? If so, where would I get one? Thanks again.

Hi Steve

If you find the speaker has come away from the frame you can glue it back. If the cone is a little warped putting some cotton between cone and frame may fix the problem? Push from the back to find the best spot..

Norm

:Sorry for sounding clueless here...but I have a 1947 Philco 48-250 that was restored "professionally" in 2001. After closer inspection, it appears that the speaker was repaired with a clear silicone. Well, that didn't last. The speaker crackles like it is falling apart. If I very lightly push the speaker material at the top, it gets clear as a bell. Is there a way to fix this, or should I get a replacement for the speaker? If so, where would I get one? Thanks again.

The best glue to use is Elmer's White Glue. It is very strong, bonds paper well, and stays flexible for quite some time (it does get brittle eventually, but usually still holds its strength). Use in very thin amounts on cracks and tears. Around the outside spider (zig-zag edge of speaker that allows cone to move in and out as a unit) us as thin a layer of glue as possible--just enough to join the paper fibers. Too much glue will stiffen up this region and throw off the mechanical balance of the cone. Some really old speakers have a leather or rubberized cloth surround instead of the zig-zag paper. This can be replaced with suede. If you have a big enough piece of suede, it can be cut out as a whole unit, but if not, working with four pieces, and then gluing the seams closed works well. You must shim the voice coil, the procedure to be described below. Then, as you are applying the suede, you must work to get a somewhat even tension all the way around the cone.

Rubber cement would seem like an excellent glue to use because it is very flexible, but after about 5 or 10 years, its bonding qualities completely disappear. Contact cement gets incredibly stiff with age, and is not so workable that you can work it into extremely thin layers, so it stays kind of thick and stiff.

You can use contact cement for the following problem, though it will not allow you to reposition the cone like Elmer's. Elmer's is much better for any repair. You just wait longer.

If the outer edge of the cone has separated from the frame, lift it gently and glue it down with Elmer's.

If you suspect that the voice coil is rubbing against the magnet, gently move the speaker cone in and out using even pressure at two places on the cone 180 degrees apart. If it is definitely rubbing, check to see if the outer edge of the cone is loose. If it is, see if pulling on this edge of the speaker cone or pushing it in causes the rubbing to go away. Do this gently. If it doesn't, glue it down as is, or if there is no lift around the outside, remove the dust cover if the speaker has one (over the center--if there is no felt or paper covering over the center of the cone, then there is no dust cover. If there is a perforated "spider" looking device that springs with the motion of the cone, and is attached with a screw in the middle, leave this alone--this is your center spider. I will explain what to do with this later.). After the dust cover has been removed, cut three evenly sized small tabs from an index card or really thin piece of stiff plastic (not plastic wrap--that's too thin). Place each of the three tabs evenly spaced apart, between the voice coil and the magnet. They should insert somewhat easily. If you must force them really hard, you should get slightly thinner material. If you force them, you may break the voice coil form. Still, they cannot be loose, either--must be a gentle snug fit. After shims of the proper size have been fitted, take a spray mister (such as an old Lysol bottle), or if none is available, use a wrung out rag soaked with water. Wet the cone evenly over its entire surface. Let this stand for many hours or over night until it dries. If you want it done sooner, you can place it in your oven. If the oven has a pilot light, this is probably enough. For faster action, or for an oven without a gas pilot, turn the oven up to about 150 or 200, and let it cycle ONCE. After the burner has cycled once, turn it off and leave the speaker sit for at least an hour.

Once the cone is completely dry, remove the shims and gently test the cone as before--two hands, each spaced 180 degrees apart. It should not rub anymore. If it does, you can try the shim procedure again, or you may just have to get the speaker reconed, or you can try the cotton behind the cone against the frame trick. This changes the bass response of the speaker, however.

If your speaker has a center spider that is screwed down and not glued down, instead of doing the above wetting procedure, you can simply loosen the screw (or screws) and put in shims. Then retighten the screws. This should correct the trouble. Some spiders are on the inside of the center of the cone, and some are on the outside of the center of the cone.

When working with a speaker, if the cone sounds like a crispy fortune cookie, be very gentle with it.

Thomas

:Hi Steve
:
: If you find the speaker has come away from the frame you can glue it back. If the cone is a little warped putting some cotton between cone and frame may fix the problem? Push from the back to find the best spot..
:
:Norm
:
::Sorry for sounding clueless here...but I have a 1947 Philco 48-250 that was restored "professionally" in 2001. After closer inspection, it appears that the speaker was repaired with a clear silicone. Well, that didn't last. The speaker crackles like it is falling apart. If I very lightly push the speaker material at the top, it gets clear as a bell. Is there a way to fix this, or should I get a replacement for the speaker? If so, where would I get one? Thanks again.

Thomas: for paper cone rips and tears, I've had pretty good luck with silicon caulk, applied with a finger tip - I prefer the clear kind, because it's less obvious. I don't have 5 year's of experience to say how it performs in the long run.

Do you have any comment on this approach?

Doug

.....Not really. The original Philco speaker problem was with silicon caulk letting go, though. Perhaps it does work well. I've heard of people using it. I don't like it because in thin sections, it is easy to tear. I suppose you just have to select the right one. Elmer's is a favorite glue for me, because it doesn't flex or move or anything. The paper flexes around it, and it just holds tight. As long as it's something that won't damage the speaker, try anything. See what happens. If it comes loose, you can try something else. If you ruin the cone, you can have it reconed, which will solve all problems.

T.

:Thomas: for paper cone rips and tears, I've had pretty good luck with silicon caulk, applied with a finger tip - I prefer the clear kind, because it's less obvious. I don't have 5 year's of experience to say how it performs in the long run.
:
:Do you have any comment on this approach?
:
:Doug

:.....Not really. The original Philco speaker problem was with silicon caulk letting go, though. Perhaps it does work well. I've heard of people using it. I don't like it because in thin sections, it is easy to tear. I suppose you just have to select the right one. Elmer's is a favorite glue for me, because it doesn't flex or move or anything. The paper flexes around it, and it just holds tight. As long as it's something that won't damage the speaker, try anything. See what happens. If it comes loose, you can try something else. If you ruin the cone, you can have it reconed, which will solve all problems.
:
:T.
:
::Thomas: for paper cone rips and tears, I've had pretty good luck with silicon caulk, applied with a finger tip - I prefer the clear kind, because it's less obvious. I don't have 5 year's of experience to say how it performs in the long run.
::
::Do you have any comment on this approach?
::
::Doug

Correct, the problem was with the silicone letting go, it was put on in May of 2001. What seems to be working now is the cotton being applied to the lower part of the cone. Sounds great now. Not sure how long it will last, but I guess I can always put in more cotton since I am restoring this for my benefit and not resale value.

Thanks again for the help. I am sure I will be needing more.

::.....Not really. The original Philco speaker problem was with silicon caulk letting go, though. Perhaps it does work well. I've heard of people using it. I don't like it because in thin sections, it is easy to tear. I suppose you just have to select the right one. Elmer's is a favorite glue for me, because it doesn't flex or move or anything. The paper flexes around it, and it just holds tight. As long as it's something that won't damage the speaker, try anything. See what happens. If it comes loose, you can try something else. If you ruin the cone, you can have it reconed, which will solve all problems.
::
::T.
::
:::Thomas: for paper cone rips and tears, I've had pretty good luck with silicon caulk, applied with a finger tip - I prefer the clear kind, because it's less obvious. I don't have 5 year's of experience to say how it performs in the long run.
:::
:::Do you have any comment on this approach?
:::
:::Doug

Did you try gluing the tear?

:Correct, the problem was with the silicone letting go, it was put on in May of 2001. What seems to be working now is the cotton being applied to the lower part of the cone. Sounds great now. Not sure how long it will last, but I guess I can always put in more cotton since I am restoring this for my benefit and not resale value.
:
:Thanks again for the help. I am sure I will be needing more.
:
:::.....Not really. The original Philco speaker problem was with silicon caulk letting go, though. Perhaps it does work well. I've heard of people using it. I don't like it because in thin sections, it is easy to tear. I suppose you just have to select the right one. Elmer's is a favorite glue for me, because it doesn't flex or move or anything. The paper flexes around it, and it just holds tight. As long as it's something that won't damage the speaker, try anything. See what happens. If it comes loose, you can try something else. If you ruin the cone, you can have it reconed, which will solve all problems.
:::
:::T.
:::
::::Thomas: for paper cone rips and tears, I've had pretty good luck with silicon caulk, applied with a finger tip - I prefer the clear kind, because it's less obvious. I don't have 5 year's of experience to say how it performs in the long run.
::::
::::Do you have any comment on this approach?
::::
::::Doug

I did. I used Elmers all purpose white glue (dries clear). Let it set for a day or so, then added the cotton. It really sounds nice now.

:Did you try gluing the tear?
:
::Correct, the problem was with the silicone letting go, it was put on in May of 2001. What seems to be working now is the cotton being applied to the lower part of the cone. Sounds great now. Not sure how long it will last, but I guess I can always put in more cotton since I am restoring this for my benefit and not resale value.
::
::Thanks again for the help. I am sure I will be needing more.
::
::::.....Not really. The original Philco speaker problem was with silicon caulk letting go, though. Perhaps it does work well. I've heard of people using it. I don't like it because in thin sections, it is easy to tear. I suppose you just have to select the right one. Elmer's is a favorite glue for me, because it doesn't flex or move or anything. The paper flexes around it, and it just holds tight. As long as it's something that won't damage the speaker, try anything. See what happens. If it comes loose, you can try something else. If you ruin the cone, you can have it reconed, which will solve all problems.
::::
::::T.
::::
:::::Thomas: for paper cone rips and tears, I've had pretty good luck with silicon caulk, applied with a finger tip - I prefer the clear kind, because it's less obvious. I don't have 5 year's of experience to say how it performs in the long run.
:::::
:::::Do you have any comment on this approach?
:::::
:::::Doug