Coffee Stains

mrwizard · 6th June 2011, 09:38 AM

Hello Alan,

i was also surprised that coffee is frequently used for that purpose. I guess the reasons are is that it is readily available, requires no safety measures, and can be disposed off in your kitchen sink.
Of course results are more consistent using new blades with well defined steel combinations (e.g. 1.2848 and 75Ni8).
Nevertheless, i thought i would give it a try and share the results

@Rasdan
Buying a ton of FeCl3 would probably be no problem anywhere in the world (especially in Malaysia with its electronics manufacturing industry), getting it in small quantities is more difficult.
Here in Germany FeCl3 is available in small quantities at electronics retail stores for PCB etching. But with PCB services becoming less expensive this is a dying hobby. I don't know if there are such store in Malaysia, but i am sure these guys know if there are: http://www.marts.org.my

Best Regards,
Thilo

rasdan · 6th June 2011, 12:28 PM

Thanks Thilo and Alan!

kai · 7th June 2011, 12:08 AM

Hello Rasdan,

Wootz and pattern welded blades can require pretty different approaches to etching. Granted, also pattern welded pieces can easily damaged by overenthusiastic staining attempts but etching wootz (especially antique pieces) is even more an art. If you really need/want to etch wootz yourself, make sure to search for similar blades (origin and age and wootz type) which are still in stain as a reference. While FeCl3 can be utilized to etch wootz this is by no means the only nor likely to be the single best approach for the majority of antique blades. There's a lot of other etchants which may be suitable or a combination of these may be needed for optimal results (quite a lot of pointers and opinions can be gathered from the net). I'd certainly recommend to try very weak dilutions first even if this needs more patience. If the wootz blade has still a nice original surface which hasn't been polished with power tools, diluted oxalic acid may be worth trying first - just a wild guess though.

Regards,
Kai

A. G. Maisey · 7th June 2011, 01:27 AM

Oh yes --- my error.

Rasdan wrote "wootz", I replied for mechanical damascus.

Sorry.

rasdan · 7th June 2011, 04:19 PM

Thanks for the pointers Kai.

I think Alan's explanation would cover wootz as well.

I am considering a few options now. Unfortunately I don't have sample blades of same origin. I am thinking of brushing a bit of citric acid on the blade to start with, but I'm not sure. I guess I'll browse and read a bit more on this area on the net. Thanks again

mrwizard · 7th June 2011, 04:50 PM

Hello Rasdan,

I don't have any wootz blades but i have frequently read that Nital is recommended for etching them. Nital is a mixture of ethanol and nitric acid. You can buy it at chemical suppliers. Don't *ever* try to mix it yoursself, if the concentration of the nitric acid gets to high it tends to explode!

Best Regards,
Thilo

rasdan · 7th June 2011, 06:17 PM

Hi Thilo,

Kaboom!! No, don't want that to happen. Thanks for the advice. It's like you can tell I'm into experimenting things.

Actually these chemical stuff is pretty hard to get here in Malaysia. There's a nutcase around KL recently goes around splashing people with acid for no reason. He is still at large. So, at the present time, I think if I try to buy any acid without proper papers, I'm certain people would give me a frighten look and dial 911.

6th June 2011, 09:38 AM	#1
mrwizard Member Join Date: May 2010 Location: Dortmund, Germany Posts: 102	Hello Alan, i was also surprised that coffee is frequently used for that purpose. I guess the reasons are is that it is readily available, requires no safety measures, and can be disposed off in your kitchen sink. Of course results are more consistent using new blades with well defined steel combinations (e.g. 1.2848 and 75Ni8). Nevertheless, i thought i would give it a try and share the results @Rasdan Buying a ton of FeCl3 would probably be no problem anywhere in the world (especially in Malaysia with its electronics manufacturing industry), getting it in small quantities is more difficult. Here in Germany FeCl3 is available in small quantities at electronics retail stores for PCB etching. But with PCB services becoming less expensive this is a dying hobby. I don't know if there are such store in Malaysia, but i am sure these guys know if there are: http://www.marts.org.my Best Regards, Thilo

6th June 2011, 12:28 PM	#2
rasdan Member Join Date: Dec 2004 Location: Kuala Lumpur Posts: 369	Thanks Thilo and Alan!

7th June 2011, 12:08 AM	#3
kai Member Join Date: Apr 2005 Posts: 3,255	Hello Rasdan, Wootz and pattern welded blades can require pretty different approaches to etching. Granted, also pattern welded pieces can easily damaged by overenthusiastic staining attempts but etching wootz (especially antique pieces) is even more an art. If you really need/want to etch wootz yourself, make sure to search for similar blades (origin and age and wootz type) which are still in stain as a reference. While FeCl3 can be utilized to etch wootz this is by no means the only nor likely to be the single best approach for the majority of antique blades. There's a lot of other etchants which may be suitable or a combination of these may be needed for optimal results (quite a lot of pointers and opinions can be gathered from the net). I'd certainly recommend to try very weak dilutions first even if this needs more patience. If the wootz blade has still a nice original surface which hasn't been polished with power tools, diluted oxalic acid may be worth trying first - just a wild guess though. Regards, Kai

7th June 2011, 01:27 AM	#4
A. G. Maisey Member Join Date: May 2006 Posts: 7,015	Oh yes --- my error. Rasdan wrote "wootz", I replied for mechanical damascus. Sorry.

7th June 2011, 04:19 PM	#5
rasdan Member Join Date: Dec 2004 Location: Kuala Lumpur Posts: 369	Thanks for the pointers Kai. I think Alan's explanation would cover wootz as well. I am considering a few options now. Unfortunately I don't have sample blades of same origin. I am thinking of brushing a bit of citric acid on the blade to start with, but I'm not sure. I guess I'll browse and read a bit more on this area on the net. Thanks again

7th June 2011, 04:50 PM	#6
mrwizard Member Join Date: May 2010 Location: Dortmund, Germany Posts: 102	Hello Rasdan, I don't have any wootz blades but i have frequently read that Nital is recommended for etching them. Nital is a mixture of ethanol and nitric acid. You can buy it at chemical suppliers. Don't ever try to mix it yoursself, if the concentration of the nitric acid gets to high it tends to explode! Best Regards, Thilo

7th June 2011, 06:17 PM	#7
rasdan Member Join Date: Dec 2004 Location: Kuala Lumpur Posts: 369	Hi Thilo, Kaboom!! No, don't want that to happen. Thanks for the advice. It's like you can tell I'm into experimenting things. Actually these chemical stuff is pretty hard to get here in Malaysia. There's a nutcase around KL recently goes around splashing people with acid for no reason. He is still at large. So, at the present time, I think if I try to buy any acid without proper papers, I'm certain people would give me a frighten look and dial 911.