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Accidently bought rough diamonds and news help polishing

Ishmael

Rough_Rock
Trade
Joined
Dec 22, 2017
Messages
9
I realize cutting at home will be nearly impossible but I wish to at least clarify the diamond appeared center. What would be a simple way to turn these rough diamonds to clean one at home using home tools or cheap tools from store
 
How does one "accidentally" buy rough diamonds?
 
I feel like this is something you can not do at home by yourself...
 
I realize cutting at home will be nearly impossible but I wish to at least clarify the diamond appeared center. What would be a simple way to turn these rough diamonds to clean one at home using home tools or cheap tools from store

Not really something you can do at home with a bit of vinegar and a potato masher :wink2:
 
The only thing that polishes a diamond is another one. You need diamond encrusted grit discs and a lapidary machine for polishing. Sorry, but not a hardware store item and certainly not a “beginner, let’s do this at home” activity.
 
It wasn' accidental it was impulse buying. I bought it off eBay and thought they were clean cut loose diamonds but I read it wrong. They are rough. I was thinking of using a dremel tool to polish and cut it some dremel tools come with Diamond grit wheels
 
This is a joke, right?!

If not, post some pictures. Rough stones can look amazing set in chunky pendants etc. Maybe we can suggest a way for you to use the stones as they are? Home polishing is not a go-er....
 
The sort of loose rough diamonds on eBay (from India I’m guessing) are heavily flawed, grayish or yellowish and dull and no amount of “cutting or polishing” will change that. It’s not like there a nice clean white sparkly “diamond” underneath. A diamond gets its sparkle from precision / carefully executed facetting at correct angles (like 58 facets) but you have to start out with clear, clean diamond rough to start with. And cutting, creating those 58 facets, reduces your original size crystal by at least 30% maybe 50%. I’d message the seller and ask very politely if you can return them for a refund because you made a mistake (but you’ll still have to pay shipping costs). The seller isn’t obliged to accept a return but it won’t hurt to ask.
 
Prefacing with this is hard and dangerous and totally against manufacturer recommendations. OSHA would not approve.... Returning the stones to get pre-polished rough would be wiser, but here is how I would do this. I'd also place my and DH's building skill in the way above average-professional level and what we can't sort out, I can call any one of many friends that are pros to explain.

You need safety glasses and a dust face mask. Diamond dust is not healthy to breath. The water system described below should be adequate, but why take chances? Given the water, I would do this outside or you need to buy a proper wet housing.

Then, it depends on how handy you are. This is not something that you can accomplish with hand-tools easily. The best tool I can think of to start with would be an angle grinder. An angle grinder it made to operate with high pressure against it and is frequently used to polish marble, granite and the like. I have a Metabo, but Makita also have good motors. A dremel or other such rotary tools motors will burn out. First you need to remove the stock shaft and housing and replace the shaft with a longer one (pretty easy, you just need the diameter).

You will need to fashion a way to secure the grinder to a solid work surface that won't vibrate from the wheel turning. You will be using the angle grinder with the grinding blade face up. So, it has to be soundly secured. You need to find a polishing wheel like below, they can also be flat, but coated with diamonds. They are not that uncommon, but you may need to visit a specialty store for tile work or metal work. Diamond pads found at typical hardware stores have poor quality and density of diamonds and won't work well. It is the diamonds that do the work, so you need to invest in good pads. Pads that have the best bet will be up to $100usd each (anything under $50 will likely fail based on my experience with other stones). If you replaced the shaft, then you have also removed the protective half-circle housing which is important to give you room to fashion a water cooling system (see below). You do not want a metal disk with a tiny coating of diamonds. That will be useless.

The next challenge is that you need a way to hold the diamond securely and keep your hands (hair, clothing, skin) away from the grinding surface. If you look at the second picture, you'll see what a lapidary uses, but this is to create precision angles. You need something more like a cabbing system, so you need to find the right wax for a dop. The wheel's rotational force will be wanting to rip things from your hands.

Here's a small shop showing the key steps including the dop and mentions his materials.

Finally, you will need water to run over the surface to cool things (which may make the grinder unhappy if you don't set it at an angle). So the water has to avoid entering the tool housing. There are grinding pads made for working dry, but I've never seem them used on gemstones. Even on harder stones like granite, you need water. If you removed the safety housing as noted above, there should be room between the polishing wheel and the motor to fashion a water capture and runoff system. Basically, you need a shallow, wide plastic bowl with a hold drilled to allow the shaft to pass through. You also need a coupling to keep water from flooding out the hole. Water can be delivered by a water hose with a reducer and then run off from a notch you cut in the water capture system.

You can also look at the 6" Hi Tech flat lap system.
https://hitechdiamond.com/shop/all-u-need-lap-machine/

If you are dedicated DIYer, here are two videos that show a home-made rig, that is cheap, but takes some time. This uses a free-standing motor with an extended shaft which is much wiser as you have more room to create a water capture system.


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It wasn' accidental it was impulse buying. I bought it off eBay and thought they were clean cut loose diamonds but I read it wrong. They are rough. I was thinking of using a dremel tool to polish and cut it some dremel tools come with Diamond grit wheels

It kinda sounds like fun if they were cheap!
 
Not really something you can do at home with a bit of vinegar and a potato masher :wink2:

Well I was going to suggest a hammer and chisel:lol:

OP, this is not something you can do at home. Special equipment is needed. If you accidentally bought it (?) just return it.
 
I feel like this is something you can not do at home by yourself...
All those years of working in my grandmother's shop and many many years of finding cheap ways to sample critters come in handy...=)2
 
The tools are expensive and the skills take a fair amount of practice. This is a bit like accidentally buying a boxcar full of lumber and asking how to make a house out of it.
Actually that might be an easier ask, Neil, considering that home-building tools and materials are readily available, along with advice from that handy neighbor or in-law we all know. :sun:

For this challenge? Even if we set sawing and girdling mechanics aside, polishing diamond is light years beyond gemstone lapping. Now if you live near Gujarat or Flanders you might find "a guy who knows a guy" with a scaife, dops and tangs in his garage. But if you're in Anytown USA you'll need to track down an established diamond recut/repair operation. In such case, be sure to have your trade control docs prepared, per US Treasury Department and Census Bureau regulations.
 
This thread is hilarious.
 
Link to ebay sale?
 
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Sure enough: the only reason I'd buy a rough diamond is to wear it as is ...

___
... then - what was done to diamonds before polishing was much of an option, is rather interesting & possibly the most $$$ historical reenactment exercise I couldn't imagine anyone wishing for !
 
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