RE: Philco 90 1-47 Triode -
Mike_RF - 06-28-2023
Thanks guys,
I probably wont be potting them in hot glue. I will use just enough to safely hold them in place.
See, this guy named Murphy and his law always seems to follow me around. If I totally pot them in hot glue, you can pretty much guarantee I will be the first guy to have one of them fail and I will have to dig it all out. If I dont pot them, it will be fine.
So just enough to hold em in. This way Murphy can take a hike
Cheers
RE: Philco 90 1-47 Triode -
Ron Ramirez - 06-29-2023
morzh Wrote:I prefer to tread safely with the temps.
Hot glue melting temps are 250F to 375F.
The application range for the Polypropylene material is -55 — +105C, which is up to 221F.
So, while I think that it might be OK (did it myself in the beginning without ill effects), I prefer to shield the caps from being immersed in the hot glue. Some contact through gaps in the shielding is OK.
For the same reason I put a paper wrap in the tubular caps' ends when I restuff them.
If anything, it will save you quite a bit of that hot glue
There are two types of hot glue - high temperature and low temperature. The temperatures you quoted are for high temperature hot glue. Low temperature hot glue, which is what I use, typically melts at 130 to 260 degrees F.
Let us therefore agree to disagree on this subject, and leave it at that. Or, as my old friend, Rev. Lowell Mason (RIP) used to say -
"You don't have to agree with me. You have every right to be wrong if you want to be."
RE: Philco 90 1-47 Triode -
MrFixr55 - 06-29-2023
@ Rod B re Post 27, Oops Yes, that is 3A 1000 PIV Diodes. 1N5408 sounds good. I am sure that a 1A, 1K PIV would work, but I'm a heavy duty guy.
RE: Philco 90 1-47 Triode -
Mike_RF - 12-21-2023
Well,
After a long pause and a few other project radios, Im am finally getting all the bits and pieced together to start this restoration.
So in my travels I have managed to find 2 speaker units for this radio. One for the dual 47 chassis and the other for the single 47.
My question is, can you swap the cones? They look like you can desolder two wires, remove the screws and separate the cone from the frame. Is this the case? If So I would like to put the better cone with the single 47 unit.
Cheers and Merry Christmas everyone!
RE: Philco 90 1-47 Triode -
Radioroslyn - 12-22-2023
The cone/vc are the same but you may have some trouble getting it off of the frame. After 90+ yrs they get stuck to the cardboard ring and all most glued to the frame. Have had some just pop off and other that I had to cut off with a sharp knife. The folds near the outside edge tend to fails, paper just fall apart requiring a new cone. On these they are 10 1/2" so you have to use a 10" cone a make a spacer to fill in the gap between the cone and frame.
When you have it apart do clean the dust from it and the gap (the area were the vc fits down in to). Dirt gets in there and restricts the vc movement deminising the speaker's frequencies response.
I just got done servicing speakers in a 21B,70B, & 90B v2. All got new cones and cords.
GL
RE: Philco 90 1-47 Triode -
RodB - 12-22-2023
I just finished resurrecting an H13 10-1/2 Inch speaker for my 650. The original opt was bad and the cone & spider was bent out of shape but the vc and field coil were good. I had planned to attempt a recone when I found an opt and Philco 650 at an estate sale for ten bucks. The cone fit perfectly in my original frame. I used contact cement around the cone's flexible edge to reinforce the paper. I left the cone slightly loose with the speaker face down on the workbench and played the radio on and off for about a week to see if some distortion could be alleviated and it worked. The vc had centered itself.
The gap for the voice coil was really dirty. I used a thin feeler gauge with a vacuum cleaner to get it clean.
RE: Philco 90 1-47 Triode -
GarySP - 12-22-2023
Some guys have all the luck! Anytime I've seen antique radios at estate sales they never had $10.00 price tags! Nice job. Take care and BE HEALTHY! Gary
RE: Philco 90 1-47 Triode -
Mike_RF - 12-22-2023
Quote:The cone/vc are the same but you may have some trouble getting it off of the frame. After 90+ yrs they get stuck to the cardboard ring and all most glued to the frame. Have had some just pop off and other that I had to cut off with a sharp knife. The folds near the outside edge tend to fails, paper just fall apart requiring a new cone. On these they are 10 1/2" so you have to use a 10" cone a make a spacer to fill in the gap between the cone and frame.
When you have it apart do clean the dust from it and the gap (the area were the vc fits down in to). Dirt gets in there and restricts the vc movement deminising the speaker's frequencies response.
I just got done servicing speakers in a 21B,70B, & 90B v2. All got new cones and cords.
GL
So.. you are suggesting disturbing the cone at all will result in the failure of the brittle surround? But thats only when you have to cut the cardboard off?
Say, where did Ron go?
Cheers
RE: Philco 90 1-47 Triode -
Mike_RF - 12-22-2023
Quote:I just finished resurrecting an H13 10-1/2 Inch speaker for my 650. The original opt was bad and the cone & spider was bent out of shape but the vc and field coil were good. I had planned to attempt a recone when I found an opt and Philco 650 at an estate sale for ten bucks. The cone fit perfectly in my original frame. I used contact cement around the cone's flexible edge to reinforce the paper. I left the cone slightly loose with the speaker face down on the workbench and played the radio on and off for about a week to see if some distortion could be alleviated and it worked. The vc had centered itself.
The gap for the voice coil was really dirty. I used a thin feeler gauge with a vacuum cleaner to get it clean.
Well using rubber cement on the surround sounds like that might be a good tip! thanks!
Did you get your cone off without destroying it?
Cheers
RE: Philco 90 1-47 Triode -
morzh - 12-22-2023
>> Say, where did Ron go?
I guess you have not visited Old Ron's recently....
RE: Philco 90 1-47 Triode -
Radioroslyn - 12-22-2023
https://philcoradio.com/phorum/showthread.php?tid=24708
RE: Philco 90 1-47 Triode -
Radioroslyn - 12-22-2023
I've used some watered down fabric glue around the edge to add some support. At 50% a few coats seems to work. On the K speakers I have some replacement cones so it not that much more work to just replace as I would recommend a good clean no matter what.
Rod, On the H13 spkr the fc/pot assembly can be removed easily by using a drift to drive the course threaded screws out. It's about one turn per 3/4". That goes for all the Philco spkr that use these fasteners. The rub is that the cone is in the way so on most of the K and the later H spkr the cones are glued in...
RE: Philco 90 1-47 Triode -
RodB - 12-22-2023
Mike_4f - Yes, the cone came off with just a little nudging at the rim of the frame.
RE: Philco 90 1-47 Triode -
Mike_RF - 12-24-2023
Quote:'ve used some watered down fabric glue around the edge to add some support. At 50% a few coats seems to work. On the K speakers I have some replacement cones so it not that much more work to just replace as I would recommend a good clean no matter what.
Now I got even more questions
1) Do you have a link to the brand of fabric glue you used?
2) Where did you get your cones from?
3) do you have a photo of the finished speaker with your spacer?
Cheers!!
RE: Philco 90 1-47 Triode -
RodB - 12-24-2023
I don't like putting a substance on the surround that makes it stiffer. I like flexible so the cone moves freer, nicer bass.