1950's era B-47

[Yggdrasil]

Are they crystals or is it a blue gray sponge like material. Being connector pins, I would expect the blue gray stuff which is tin nitrate (Metastatic acid)... Kind of a pain in the butt to filter out, but doable. There is a process to deal with metastatic acid, but I've never tried it.

I assume your gold foils are trapped in the crystal material?

You got some pictures?

Meta stannic acid is a form of Tin Oxide, H2SnO3.
Still a pain in the ***

 

[nickrpotts]

So I found I can peel the plating on the circuit boards up saving me the hassle of removing solder and cutting up to run through ap...but it's only plating on a silver colored non-magnetic metal....anyone have any clue as to what metal it is? Am hoping it's silver but am doubtful at the same time.

Can you show the silver coloured tracking? As I am not seeing it in your pictures?

Pic 599. I see a PCB showing evidence of the track being removed/peeled of so lighter in colour, as it has seen no chemistry or air over the last 50+ years. Next to gold plated tracks, ending with tin tin/lead soldered pads making connection from side to side on the PCB. These very old so it is likely the connection was made with the metalised pin on the component and then soldered from the back and the solder has wicked up the pin.

Pic 948. What I am seeing from your photo's is gold plated copper tracks, with what I believe is tin/lead solder (due to age) which appears to run up the end of the track. The brown is the reverse side oxide treatment put on the back of the copper track to improve its adhesion to the PCB material.

PCB chemical manufacturers use proprietary formulas of nitric acid, ferric ion, anti tarnish in suspension for their chemistry for removing tin/lead. So if you have a fume cupboard, to prove what you have, I would take a length of the tracking and put in some dilute nitric acid, and it's likely within 3-10 minutes you'll just be left with the gold foil. The time will vary as I don't know what the thickness of the copper.

 

[Flying Farmer]

Thank you very much for taking the time to reply with such detailed explanations of what everything is! I had used Google lens to try to be identify parts and it was not very accurate at all.

I almost don't want to scrap these pieces because they're probably worth more to a collector, but it's not as much about the money as it is about the process of finding and refining material.

Thanks again!!!

May I offer? You’re unlikely to find anyone restoring a B-47 as they’re too expensive to work on/fly and they have no curb appeal like the P-51. That would be about the only market where someone would want them intact. B-29 or B-17 would be a different story. I think using these units to learn refining is about the most noble application left.

 

[Alondro]

Red: Transistor, potential for interior gold plate and solid gold bond wires.
Green: Tantalum foil capacitor, no precious metal, can be sold as is to a recycler.
Yellow: Relay switch, will have solid alloy contacts. Silver and palladium are possible and sometimes gold plated.
Blue: Carbon resistors, potential for gold plated end caps.

Janie

For a military aircraft, the relay switches might even have solid gold contacts. Super-high-end old relays were made to take no chances with a contact failure. I had some boards from a dismantled 1976 nuclear launch control computer. There was gold EVERYTHING. Large canister transistors plated inside and out with gold, with solid platinum contacts to the silicon wafer. All sorts of other components made with the most high-end materials. Early generation MLCCs the size of postage stamps with thick palladium electrodes. Connectors with hundreds of pins, all with thick gold plating so heavy it sinks straight down when all the copper inside is dissolved and the foils are swirled in the jar. Tantalum caps with silver casings. My jaw hit the floor when I opened the box of those boards.

 

[wisco_gold]

For a military aircraft, the relay switches might even have solid gold contacts. Super-high-end old relays were made to take no chances with a contact failure. I had some boards from a dismantled 1976 nuclear launch control computer. There was gold EVERYTHING. Large canister transistors plated inside and out with gold, with solid platinum contacts to the silicon wafer. All sorts of other components made with the most high-end materials. Early generation MLCCs the size of postage stamps with thick palladium electrodes. Connectors with hundreds of pins, all with thick gold plating so heavy it sinks straight down when all the copper inside is dissolved and the foils are swirled in the jar. Tantalum caps with silver casings. My jaw hit the floor when I opened the box of those boards.

Any chance you have some pictures you'd be willing to share? I do a lot of reading and researching but am still stumped trying to identify what metal is what. Gold is obviously fairly easy and you're not kidding when you say it is everywhere!

I was just reading up on silver refining and learned that silver precipitate can turn gray, black and purple...kind of the like the mess I had except there are shiny crystals in some of the filters that I saved. I'm thinking the connecters were gold plated silver. I'm attaching a picture of a the last of the material i filtered off from what I thought was a failed attempt and some pictures from the other day if the multicolored precipitate.

Also could you give me some ideas as to what metal the parts in the last pictures are made of? There appears to be no gold plating and I would assume it would be some pm.

Thank you for your help!

 

[wisco_gold]

Can you show the silver coloured tracking? As I am not seeing it in your pictures?

Pic 599. I see a PCB showing evidence of the track being removed/peeled of so lighter in colour, as it has seen no chemistry or air over the last 50+ years. Next to gold plated tracks, ending with tin tin/lead soldered pads making connection from side to side on the PCB. These very old so it is likely the connection was made with the metalised pin on the component and then soldered from the back and the solder has wicked up the pin.

Pic 948. What I am seeing from your photo's is gold plated copper tracks, with what I believe is tin/lead solder (due to age) which appears to run up the end of the track. The brown is the reverse side oxide treatment put on the back of the copper track to improve its adhesion to the PCB material.

PCB chemical manufacturers use proprietary formulas of nitric acid, ferric ion, anti tarnish in suspension for their chemistry for removing tin/lead. So if you have a fume cupboard, to prove what you have, I would take a length of the tracking and put in some dilute nitric acid, and it's likely within 3-10 minutes you'll just be left with the gold foil. The time will vary as I don't know what the thickness of the copper.

You were correct; I initially seen silver color running farther down the strip than I thought solder would so assumed it was silver.

 

[MicheleM]

Board from a nuclear launch control computer? Wow! I would like to see some pictures

 

[Alondro]

Board from a nuclear launch control computer? Wow! I would like to see some pictures

Alas, I dismantled them last year. I do have some of the components. I'll see about scrounging them up.

 

[Alondro]

Any chance you have some pictures you'd be willing to share? I do a lot of reading and researching but am still stumped trying to identify what metal is what. Gold is obviously fairly easy and you're not kidding when you say it is everywhere!

I was just reading up on silver refining and learned that silver precipitate can turn gray, black and purple...kind of the like the mess I had except there are shiny crystals in some of the filters that I saved. I'm thinking the connecters were gold plated silver. I'm attaching a picture of a the last of the material i filtered off from what I thought was a failed attempt and some pictures from the other day if the multicolored precipitate.

Also could you give me some ideas as to what metal the parts in the last pictures are made of? There appears to be no gold plating and I would assume it would be some pm.

Thank you for your help!

Hmm, cut off a piece and toss it in 50% nitric-50% distilled water. Let it react for a while. If it dissolves, it's just brass. If not, it could be solid gold. Probably not pure gold, since that'd be too soft. You'd still need to refine it if it doesn't react with nitric.

 

[Alondro]

Here are a couple from the launch control boards.

These are the big gold canister transistors.

 

[Alondro]

And here we have one of the huge early-generation MLCCs, with the plastic scraped off one edge to show the electrode metal.

 

[wisco_gold]

I tried posting a response to this the other night, it must not of posted

Here are a couple from the launch control boards.

These are the big gold canister transistors.

These were one of the first things I discovered were gold plated and seen how many I had and was estatic! It's only gotten better the more I dig into it. How did you process yours?

And here we have one of the huge early-generation MLCCs, with the plastic scraped off one edge to show the electrode metal.

I've found a couple of these so far; what are the foils made of?

 

[Alondro]

I tried posting a response to this the other night, it must not of posted


These were one of the first things I discovered were gold plated and seen how many I had and was estatic! It's only gotten better the more I dig into it. How did you process yours?

I've found a couple of these so far; what are the foils made of?

The transistors I haven't processed yet. That's a new picture of them. I've only tested one in nitric acid, which dissolved the insides and left the gold foil, the platinum electrodes, and the chip. Some silver chloride did drop out of what dissolved after salt water was dripped into it, so the canisters appear to be a silver alloy under the gold.

I haven't tested the large capacitors yet to see what the electrode metal is, just saving them for now with the rest of my MLCCs.

 

[wisco_gold]

The transistors I haven't processed yet. That's a new picture of them. I've only tested one in nitric acid, which dissolved the insides and left the gold foil, the platinum electrodes, and the chip. Some silver chloride did drop out of what dissolved after salt water was dripped into it, so the canisters appear to be a silver alloy under the gold.

I haven't tested the large capacitors yet to see what the electrode metal is, just saving them for now with the rest of my MLCCs.

Wait so the electrodes on the transistors are platinum? I have such a hard time figuring out what's what. I find a part by Google search and can never seem to find detailed specs on said part. If you have any tips for me there it would be greatly appreciated and do you have any idea of what the legs are made up of on these vintage military PCBs?

 

[wisco_gold]

For instance I saved these foils and other unknown metal pieces because they came out of what I believe to be capacitors from one of the boards I've been working on. Composition is yet to be determined.

 

[nickrpotts]

Wait so the electrodes on the transistors are platinum? I have such a hard time figuring out what's what. I find a part by Google search and can never seem to find detailed specs on said part. If you have any tips for me there it would be greatly appreciated and do you have any idea of what the legs are made up of on these vintage military PCBs?

I always thought the electrodes in old high end MLCC's were palladium as opposed to platinum.

 

[Yggdrasil]

I always thought the electrodes in old high end MLCC's were palladium as opposed to platinum.

I think you are right, but there are so many iteration of components over the years so it can be possible.

 

[nickrpotts]

I always thought the electrodes in old high end MLCC's were palladium as opposed to platinum.

Maybe weigh the pieces, Palladium is around 11g/cm3, Platinum is around 21g/cm3.

 

[wisco_gold]

Maybe weigh the pieces, Palladium is around 11g/cm3, Platinum is around 21g/cm3.

That I can do; these would be the electrodes correct?

 

[nickrpotts]

That I can do; these would be the electrodes correct?

Yes, It would just give you an idea without access to xrf if it was more likely platinum or palladium