The PHILCO Phorum
An attempt to remove the Field Coil from a G speaker - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: An attempt to remove the Field Coil from a G speaker (/showthread.php?tid=25620)

Pages: 1 2 3

RE: An attempt to remove the Field Coil from a G speaker - morzh - 02-19-2025

So, considering that Google gives me this when looking for 45 RPM spider,

https://www.etsy.com/listing/1520562643/spider-45-rpm-record-adapter?gQT=1


where do we get them?

RE: An attempt to remove the Field Coil from a G speaker - Ed Locker - 02-19-2025

Last time I needed one of those, I ended up making one using a milk jug, scissors and a exacto knife.

RE: An attempt to remove the Field Coil from a G speaker - Arran - 02-19-2025

Mike;
I've made a one or two spiders by using some card stock, and a razor blade, it took more then one try but they did work, and looked convincing.
Regards
Arran

RE: An attempt to remove the Field Coil from a G speaker - Arran - 02-19-2025

Mike,
This is just a thought, the are on the coil where the verdigris (green oxidation is) I wonder if that is where the break is?? It may be possible, since the coil is not varnished together, to splice the wire back together, from what I understand filed coils are bulk wound, so the direction, and pattern of the turns isn't critical. If you have an empty spool you could unwind the coil onto it, till you find the break, repair it, and then wind it back on, though the bobbin then used doesn't look easy to do this with. This is assuming you want to spend the time repairing the speaker, but it's kind of like repairing an 8 track cartridge, it's sort of like knitting even though you can buy scarves and sweaters from the store.
Regards
Arran

RE: An attempt to remove the Field Coil from a G speaker - morzh - 02-19-2025

Arran

The oxidation seems to go deep, a few layers. The break starts right there, but then it will occur on every layer for a few layers thereafter. I could keep unwinding it until I find where it stops, and it is quite possible the number of layers will be limited to a 2-3 00 Ohms, which would be acceptable. But it is not a given. It is a spot that permeated through, all the way to the place where the wire was coming out of the paper.
Yes I'd like to repair this, if only to gain a basic training, as I am yet to repair my first speaker. Depends on how well I do with replacing the coil and repairing the spider.
I do not even know how to glue the spider back, and keeping the cone vertical strictly perpendicular to teh spider.
I need for someone to guide me through.

RE: An attempt to remove the Field Coil from a G speaker - morzh - 02-19-2025

So,

Q1. Does anyone know where to get the spider.
Q2. If there is no such place, what material is best? I doubt tin is good as it is not springy enough. Phenolic...how long will it last? Cardboard/dense paper...what else?
Q3. How to glue it to the cone?
Q4. if the cone has the remnant of spider on it: how to remove it, so the new spider can be glued?
Q5. What glue to use for spider to cone and cone to basket rim?
Q6. What is the detailed procedure of putting the cone back?
Q7. Should I use a new cone?

RE: An attempt to remove the Field Coil from a G speaker - RodB - 02-20-2025

Q8. What's the meaning of life?

I have read that someone made a spider out of the clear plastic from bubble packaging. It's flexible enough to produce bass response and stiff enough for the highs. I made one but never used it. Wasn't that hard to do, use sharp scissors.

RE: An attempt to remove the Field Coil from a G speaker - morzh - 02-20-2025

Rod,

Bubble packaging? The one I know (if you mean the large bubble type) is really thin. I have some at home.
Is there the other type?

Here's a thought: what about thin Lexan/Plexyglas?
Also, should the end of the hooks be bent to glue to the cone inclined surface? Yeah, Lexan will be too rigid for that?

RE: An attempt to remove the Field Coil from a G speaker - GarySP - 02-20-2025

Mike, give this site a look for your spider. Can't hurt. https://www.simplyspeakers.com
Take care and BE HEALTHY! -Gary

RE: An attempt to remove the Field Coil from a G speaker - Paul Philco322 - 02-20-2025

I am late to this post, amazing amount of work for a speaker Mike. You must like the challenge. I have a speaker from an old RCA T62 that you saw in my "finally" post. It is a six inches field coil. The cone is kinda messy several repairs. Would it help you in any way, I do not know its specs. Paul

RE: An attempt to remove the Field Coil from a G speaker - morzh - 02-20-2025

Paul, thanks,

Anything can help.


Gary

Thanks, lemme look!

RE: An attempt to remove the Field Coil from a G speaker - morzh - 02-20-2025

Paul, thanks,

Anything can help.


Gary

Thanks, lemme look!
PS. Looked it up. They have kits and parts for modern speakers.

Here's a thought: can I use a modern spider as a material donor to cut a spider from? The challenge is, all of them have a minimum 1" hole in the middle, and I need the whole thing to be below that.
Another thought. Can a modern spider be used in the same way as it is used today, using the part around the cone to glue to?

RE: An attempt to remove the Field Coil from a G speaker - RodB - 02-20-2025

No Mike. Clear plastic from the packaging of items you buy at Home Depot, the ones you can't open without a hack saw or utility knife. Use the flat area to trace the spider. Here's a picture.
   

RE: An attempt to remove the Field Coil from a G speaker - morzh - 02-20-2025

Got it. Still did not get the "Bubble" part.

RE: An attempt to remove the Field Coil from a G speaker - RodB - 02-20-2025

The part/tool you get from HD is inside the plastic, like in a bubble.