First Small Batch...I'm Hooked!

[Alondro]

Very nice cocoa powder! Well done. Lucky you to have found the GRF and Hoke before you ever started; I muddled my way through a few batches learning lessons the hard way until I found the light here.
I also have 25 lbs (~12 kg) of RAM cards with fingers to process. But these are fully populated with chips, so first I place them on a hot plate to soften the solder and easily remove them with a paint scraper. Now I’m also considering trimming off the fingers or processing them whole. A knowledgeable Home Depot guy suggested a small band saw, where the blade always runs down (safer). But the cards are only 1” (2.5cm) wide, which means your fingers get kinda close to the blade. Need to rig up some sort of wooden block spacer and pushing stick device to do this safely and quickly. Anybody out there have any suggestions or have done this before?
Cheers!

You can use tin snips to cut off the fingers. The chips on mine I popped off with a small old knife I'd ground the pointed tip off and ground into a chisel-like tip. Getting under the edge of the chip and giving a tap popped them off easily for the more modern RAM cards. Those with the wire leads, I just cut down one side with the knife, popped up, and then pulled off. Did it while watching TV.

 

[Yggdrasil]

Lead will go with Tin in HCl.
But any gold traces that might or might not be on the surface of the PCBs is going to yield next to nothing.
So the question is if it’s worth the effort.

 

[Shark]

I trim mine with a small metal shear from Harbor Freight. The chips come off in a rotisserie oven using a basket similar to a toaster for an open camp fire. Takes maybe 8 to 10 minutes to do a pound. Leave enough room for the chips to slide around inside the basket and it helps pry off the ones that are loose.

 

[Shark]

short clip of the chips being removed.

 

[soutex]

I've only done RAMs once and nowhere near finished with them, so not sure if my comments are even valid.

Considering the legs of ICs are cheap base metal I don't bother taking them off cleanly by desoldering because, in my opinion, the legs are waste material anyway - I don't see the (monetary) value in recovering that. I use a straight screwdriver and run that beside the body of the IC a few times so it breaks the legs. The added bonus is I then have less waste material to process before I can process the chips further.

As for whether to keep the boards whole or not and whether there is anything else worth anything, you will find surface mounted capacitors that should have Palladium - atleast my research says to keep the tan colored ones, anyway. The flat part of the screwdriver and a little sideward pressure works well at breaking those off too. Cut the fingers off the card. The gold only goes as far as to ensuring a durable connection with the motherboard RAM slot. Under the soldermask, it is Copper.

On a sidenote as an FYI, I once had a Chevy Blazer and in the back, mounted to the ceiling, there was a detachable light that took rechargable batteries. It didn't work so I stripped it. There appears to be a LOT of gold plating on it - I'm of the belief that any automotive electronic device considered for "emergency" use or a safety device will contain gold plating on the PCBs that can be processed along with the RAM fingers. Cellphones and calculators too, if I'm not mistaken.

 

[Ohiogoldfever]

some rams have gold beside the fingers, I am thinking how I could get rid of the lead and thus de solder the chips at the same time and separate MLCC's or whatever smaller electronics are there as well. The AP without H2O2 just the bubbler, is great but I still don't know if solder (which cold contain lead) is going to affect everything. According to the reactivity series table the lead will make the copper which was dissolved to become solid (cement out) and then you need to separate gold from lead? Removing lead first with an acid bath?

I find AP pretty forgiving. Just use one labeled vessel for dissolving solder. Then move them once the solders gone.

I have a few 1.5 gallon buckets with lids that have been going for better than a year now. Once you’ve got the cycle down it’s just a matter of moving things every now and again.

If you keep emptys it’s easy to pour off the solution, rinse things clean with Freash HCL poured into the same solution.

Then AP into the bucket. Moving liquid rather then the material is helpfully

 

[dpgold]

I find AP pretty forgiving. Just use one labeled vessel for dissolving solder. Then move them once the solders gone.

I have a few 1.5 gallon buckets with lids that have been going for better than a year now. Once you’ve got the cycle down it’s just a matter of moving things every now and again.

If you keep emptys it’s easy to pour off the solution, rinse things clean with Freash HCL poured into the same solution.

Then AP into the bucket. Moving liquid rather then the material is helpfully

I am not sure I understood everything, should I keep an AP batch separately to remove the solder and then use another AP batch to separate the gold foils? Should I wash the material well of traces of solder before I put them in a new batch?

 

[Martijn]

Read this tread:
https://goldrefiningforum.com/threads/cemented-palladium.27212/

 

[dpgold]

thank you

 

[Ohiogoldfever]

thank you

Yes, I remove solder in one bath, pour the solution into another bucket, rinse the material with HCL. Pour that rinse material into the solder bucket.

Then use copper chloride to remove the foils and proceed.

The tin or lead is easy to deal with as long as you keep it separate from your remaining solutions.


If my solder (tin) bucket contains foils it’s easy enough to filter them and rinse before adding to another batch.

I don’t recover and refine in one batch. Rather a series that ends up where it needs to be.

One of the quarks of using AP to liberate the values. Remove the foils with AP, rinse, then refine.

 

[offtrailhiker]

Since I am not pressed by time to refine my fingers and I am doing it mostly for hobby, i have a different approch to fingers. I try to separate them mechanically and delay to work with acids as much as possible (obviously until refining) and create as little waste as possible.
I have made a video posted on youtube ( )of removing finger foils with soldering iron. I am working to develop the best way of processing RAM sticks with almost zero waste (half way there, the process exists I just have to build the machinery for it ).
Right now like others stated trimming with a metals sheet cutter works, then AP then refining.

Be safe.

Pete.

That's great information. IDK how ewaste ben has like a million subscribers to your 100. Well, you just earned another subscriber, anyway.

 

[MvK]

I have one of those old metal shears that you can screw down on your workbench. I did have to customise the knives to cut closely to the chips because they are used for flat stuff only.

I use them to cut the worthless parts of board off to save space in my stockpile.

Picture is not mine but its about the same type.