The authoritative public forum
  for Metal Finishing since 1989
  

  -----

Need information on non-cyanide jewelry bombing

May 1, 2010

I need information on bombing for jewelry pieces.
Is there any other substitute which does the same work as bombing does.Like any machine or electropolishing or plating which can make white gold jewelry more brighter.
It should be non-cyanide based because we are located in Dubai where using of cyanide is banned.
Please reply me its urgent.

Kamlesh Gupta
jewellery manufacturing - Dubai, United Arab Emirates

---

Bombing is same as a stripping. it removes upper layer of metal; due to this the article brightens. it also loses gold. you use stripping machine of Fioa International or Herculeous. You better search on net. According to me they provide stripping salt also. But I think it contains cyanide. You contact them and ask about your problem.
after your feedback,again I will give answer to your questions.

Bhupesh Mulik
jewellery - Mumbai, India
May 5, 2010

---

Mr. Bhupesh Mulik.
Thanks for your reply.
Previously we worked with Stripping machine also, but we didn't got the proper results, after doing the stripping there is still blackness in gaps between two diamond sockets. And its looks very ugly.

Regards,
Kamlesh.

Kamlesh Gupta
- Dubai, UAE
May 10, 2010

---

Hi,Kamlesh sir
the blackness between diamonds sockets or channel is because of carbon remains during lost wax process . concentrate on wax pieces qc on microscope.if still there is problem than after stripping, you boil pieces into HCl than direct dip into ultra which contain basic salt solution to acid-base reaction takes place. than use steam jet on pieces and see the result.

Bhupesh Mulik
jewellery - Mumbai
May 11, 2010

---

May 19, 2010

Dear,
Bhupesh.
Thanks for your reply.
We are making few Necklaces with linking the sockets to each other like a joint or hinge etc, Thing is that when we solder it turns black and gaps between the sockets are so less that we can't polish it also. We tried doing boiling in HCl. even though we are not getting the results.
And recently we have started doing Diamond wax setting casting, its seems that all the diamonds are looking black, and the same design ring we set with manual setting, the diamonds looks more bright in the manual setting.Is there any way to remove the blackness.
Please let me know.
Thanks in advance.

Kamlesh Gupta
- Dubai, UAE

---

hi, Kamlesh
you first dip your pieces or necklace in a mixture of boric acid powder and acetone ⇦ this on eBay or Amazon [affil links] Warning! highly Flammable! . heat the pieces slightly so that acetone volatilizes. than cool the pieces and dip into mix of 10% H2SO4 and water . boil it for 15 min. don't take H2SO4 more because it effect on your purity.

Bhupesh Mulik
jewellery - Mumbai, India
May 19, 2010

---

Mr. Bhupesh.

Thanks for your reply. I will try with this process and let you know the results.

Kamlesh Gupta
- Dubai, UAE
May 23, 2010