[jerryhawthorne]

I don't know about you Ron, but tomorrow, I'm off to the store and look for semichrome. Should spiff up the 38-116 cans I'm working on.
Jerry

[Bob Andersen]

It is kinda pricy, but a little goes a long way. That can has lasted me years. Look for the little 1.76 oz tube.

[Arran]

I don't think it's available everywhere like in Walmart but some of the auto parts stores may have it. I've never bothered polishing aluminium, I've usually been content with a bright but a matte finish on IF cans and the like, which is pretty close to how most of them were when they were new.
Regards
Arran

[Bob Andersen]

I posted a video on YouTube last night about these rusty speakers and received some tips about unmounting the larger speaker cone and decided to give it a try. I removed the screws around the perimeter and very carefully separated the cone from the frame then removed the spider screw. Success Now I can really get in there and tackle that nasty rust

The cone is glued right to the frame in the smaller speaker. I'm not sure it's possible to remove it without damage.
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[jerryhawthorne]

Bob, your a braver man than me! Good luck and post pics as you go through it. I never had the confidence to remove and replace a cone, always sent speakers to someone who knows more than me about that stuff (most everyone). I will be watching your progress.

Jerry

[w4rtc]

WOW
Ditto, you are brave, if that was me I would have screwed up that voice coil. Good work and good luck on putting it back together. . Joe

[Ron Ramirez]

Not sure about the K series (8 inch) Philco speaker, but on newer speakers with a cardboard gasket, a careful application of straight acetone will allow the outer edge of the cone to be removed from the frame. You have to apply the acetone, let it sit for 10-15 minutes, and carefully start to remove the cone edge from the frame. One or more reapplications may be needed.

Phorum member Ed Locker showed me that trick a few years ago.

Speaking of tricks, thanks much for the Simichrome tip. I've been using Mother's Mag & Aluminum Polish on IF cans, but it doesn't seem to work as well on the 1930s Philco coil and IF shields that were spun permanently onto the chassis.

[Bob Andersen]

Thanks for the suggestion Ron. I just gave it a try and it worked quite well However, the cone was in pretty crummy condition to begin with so I'd like to replace it.

Does anyone have an opinion as to what replacement cone to use ? I measure about 7.5" O.D. I'm contemplating an 8" from MAT Electronics but am not sure if it will fit properly.

http://matelectronics.com/prestashop/en/...sories?p=3


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Ugh. I'm glad I popped the cone out. This really needs to be cleaned out properly for the voice coil to move freely.
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[Bob Andersen]

After three days of rust stripper, the speakers are finally rust free
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[Arran]

As long as the center hole is small enough that you can mount the voice coil and spider to it it should work, do those have a foam or a paper hinge/surround? Or is it rubber? I too have known about the acetone trick for removing a glued on cone, actually lacquer thinner works just as well. You don't really need to let soak as long as 15 minutes, 5 to 10 is usually sufficient. You can use some strips of film negative or some other thin yet stiff plastic to shim between the voice coil and the pole piece.
Regards
Arran

[Bob Andersen]

I think the MAT Electronics cones have foam surround. I ordered a few and hope to have them by the end of the week. I was thinking I could leave some of the old paper cone attached to the voice coil / spider if needed to bridge a gap to the new cone.

[Bob Andersen]

Now for the output transformer. A little drilling took care of the rivets.

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[Ron Ramirez]

All of the cones I have found so far have foam surround. I got lucky and bought several 8 inch cones on eBay a few years ago. The center holes are a bit small, but that is easily corrected by carefully cutting with a good knife. The depth is perfect for Philco "K" series speakers but too deep for Philco "S" speakers which need a shallower cone. The surround requires a bit of trimming as well to fit the pincushion frame.

You're doing a fine job with those speakers, Bob!

[Arran]

Some newer speakers have a synthetic rubber surround/hinge but the foam ones are almost as common as the paper ones were. In the past there were a lot of problems with the foam disintegrating, especially the orange colored foam, you see a lot of replacement kits for sale for those types. I like the speakers that used a leather or chamois surround/hinge, they seem to be the most durable provided they were stored properly.
Regards
Arran

[Bob Andersen]

My order from MAT arrived and the cone was even better than I expected. Just a little trimming on the surround and it will fit perfectly

Before I mess around with installing it though I think I'll try out the original cone.
[Image: http://farm9.staticflickr.com/8363/84207...9484_c.jpg]

The depth is a pretty darn good match.
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