Gold plated boards 22" x 16" - How to process

[newlife]

Hi Everyone!

I haven't been on here in a while, but when I was active I recovered and refined about 1.5 troy ounces of gold! Fun stuff!

Since then I realized that recovering and refining is A LOT of work. Profit margins are very low...

Which leads me back here to ask for advice.

I have over 1,000 lbs of these boards. The edges are all gold plated. Some of these look like they came from SanDisk (I saw the logo on some of these).

1) Has anyone dealt with this kind of scrap? They are 22 inches by 16 inches. Gold plated boarders.10 of these sheet together are very heavy...

2) Should I cut the edges of the boards so they look like fingers from PC Cards...they are pretty thick... what tool should I use? An electric saw?

3) Should I sell this to a refiner? If so, does anyone know of a good one in Northern California?

Thanking you all and this forum in advance!

 

[philddreamer]

Where about are you in California?

Phil

 

[Geo]

Band saw with fine teeth. Leave a good margin between the blade and gold trim but don't be too generous.

 

[newlife]

Band saw with fine teeth. Leave a good margin between the blade and gold trim but don't be too generous.

Can you suggest a good affordable band saw? Assuming would want one that I can bolt down?

And Thank you for your reply!

 

[Geo]

Since you are cutting only the fiberglass boards, a minimalist piece of equipment should work great. It needs to be a stand up model so you have both hands free. http://www.harborfreight.com/garage-shop/stationary-band-saw/9-in-bench-top-band-saw-60500.html

 

[Claudie]

Since you have so many, I think I would try using a rectangle shape plastic tub and process them in AP the way they are. It doesn't appear that there are any components on the boards, so you wouldn't have to be concerned with a lot of trash in the mix. Cutting them with a band saw is going to cause quite a bit of particles floating around in the air, not to mention the extra work & expense.

Edit: Spelling :|

 

[Geo]

If the boards lay against each other, the AP solution will have a hard time doing it's job. You would have to create a space between each board away from one another. With the volume, It would take either a very large container and thus a large amount of solution, or doing a few boards at a time which will take a very long time. It's a trade off either way. Manually trim the boards or be prepared to be inventive on creating a basket to stack them up edge to edge.

 

[g_axelsson]

Before doing a lot of work and investing a lot of money I would run a small test batch to see how much gold you have. There is a large difference in thickness between gold plate or ENIG (Electroless Nickel Immersion Gold, gold flash) and you have a hard time to spot the difference without testing.

A vice turned on it's side and with the jaws adjusted just a bit wider than the board thickness is a perfect tool to break the boards manually. No expensive tools.
It breaks the board down into a bit larger pieces than cutting close to the gold but it works almost as fast as close cut boards. Just put the board in and press down. When I did fingers I did a board in just seconds.

Göran

 

[rickbb]

I'd go the cheap table top band saw route and then AP in a 5 gal plastic bucket with a lid. You can get them from Lowes or Home Depot cheap. Put a couple of small holes in the lid for the air hose and a vent. Run it in batches about 2/3 full of liquid. You could do several buckets at a time to help speed things up, but then you'd have a lot of liquid to process and deal with waste.

Let it bubble away all day, and then pick up the bucket and slosh it around good to stir the parts to prevent them from sticking and covering each other up. Obviously don't slosh it so hard you spill stuff, just enough to mix up the parts.

Might take awhile, but you're only dealing with it for a few minutes a day. Once you have all the foils off, then you can drop down to smaller beakers to process the foils.

 

[Claudie]

Never pick up a bucket by the handle. The metal handles will corrode because of the acid in the bucket. I picked up a small bucket once, that had a plastic handle on it, and it snapped in the middle. It didn't have anything dangerous in it at the time, but that was my warning. Even if the handle is plastic, don't trust it. After the handle snapped like it did, it makes me wonder about how the plastic buckets are effected by the chemicals. Maybe it was just a defective handle, who knows, but I won't be picking any buckets up by the handle any more. :|

 

[Geo]

I doubt the chemicals is what degraded the plastic. Sunlight and oxygen is what I would suspect. Exposed plastic gets more brittle as time goes on.

 

[goldsilverpro]

Never pick up a bucket by the handle. The metal handles will corrode because of the acid in the bucket. I picked up a small bucket once, that had a plastic handle on it, and it snapped in the middle. It didn't have anything dangerous in it at the time, but that was my warning. Even if the handle is plastic, don't trust it. After the handle snapped like it did, it makes me wonder about how the plastic buckets are effected by the chemicals. Maybe it was just a defective handle, who knows, but I won't be picking any buckets up by the handle any more. :|

My experience is totally different. I've used plastic buckets for at least 40 years, always with wire handles, and have never had a handle break. Never. I always lift them by the handle. If the handle looks rusted or corroded, I just don't use it. Many days I probably lifted and carried or raised 40 or 50 buckets full of solution by the handle. To me, it's safer to lift it by the handle than any other way I can think of. However, I would never use a bucket with a plastic handle. They've always seemed flimsy and I never trusted them.

 

[Claudie]

I have carried many a bucket by the handle too, never had a problem, but when the small one broke on me, I kept thinking "what if that had been full of chemicals?". I guess I have handlephobia now. :|

EDIT: Spelling

 

[johnny309]

Very good surface.
If I have to process those I choose nitric acid.
Why?
Because is fast(I can handle 4-5 boards at a time....in a container without sticking to each other)
The boards are clean of solder.....so that leaves copper ,nickel and gold.....and the green solder mask
And .....the foils would came clean...