gemfeller
Cave Dweller
Member since June 2011
Posts: 3,786
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Post by gemfeller on Dec 22, 2014 1:44:42 GMT -5
39don, some smiths go so far as to go back and create fire scale over the entire piece then give it a wire-brushed finish. Oxidizer seems like a much better/quicker solution.
For some reason I've been lucky and haven't had many fire scale problems in fabricated work. Casting's another story...
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jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
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Post by jamesp on Dec 22, 2014 7:12:04 GMT -5
This may not work on silver, but does well on about all base metals including stainless. 1) Tumble rough base plates pre-cut with shears with smooth tumbled granite pea gravel to remove shear burrs leaving a frosted finish. 2) Have railroad anvil and all hammer faces polished to 3000 grit mirror finish(wet diamond pads 100-200-400-800-1500-3000) No dents in hammer or anvil. 3) Use almost a flat faced hammer to hammer finish a smooth surface, more rounded hammer face to get a hammered look 4) Polish on a 3600 RPM buff with generous stick tripoli applications That process avoids all sharp abrasive except the tripoli. Basically a smooth hard finish imparted by a polished hammer/anvil combo. Tried tumbling the soft metal base plates to a polish finish with various methods after coarse grinding the shear burrs off. Always failed. So the hammer finish. Don's initial question about tumbling with 1000 grit....tumbling agate in 1000 grit may yield a bright shiny finish. Tumbling softer rocks in 1000 grit will give a fair polish only after vigorous tumbling. The softer the rock the more vigorous the tumble required. Not sure that delicate soldered silver pieces would hold up to such, especially with the unreachable nooks and crannies. My guess is that the only way to put a finish on a complicated shape is blasting with appropriate media. With some form of a small hand held blasting probe in a blast box. That way you could aim the probe/gun in the nooks to get a finish. Media could be small stainless balls, glass beads, no telling. Bet there is a recipe of some sort. Basically a micro hammer finish. peened to look flat and polished. Perhaps walnut shells, some may be available laced with polish. I know no other way to finish metals quickly with nooks and crannies. www.jewelerstoystore.com/Sand_Blasting_Supplies_s/321.htmwww.jewelerstoystore.com/Abrading_Station_2100_s/774.htmFancy medias www.optaminerals.com/Abrasives/Walnut-Shells.html
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Post by rockjunquie on Dec 26, 2014 16:38:43 GMT -5
I have learned to live with the nature of the beast!!!!!!!!!! I do one of two things remove it by polishing or oxidizing. This conversation about fire scale comes up when I am just starting to add a new topic on my silversmithing on the Forum. I'll start here first. James, one of your problems with the solder is you are using too much solder, lighten up a bit. A pendant I finished today had so much fire scale if I had polished/buffed it off my silver base plate (24gauge) would have been no more. I had purchased an oxidizer from Rio Grande recently so I wanted to try it out anyway. I oxidized it per directions and brushed it with a fine stainless steel brush. On this next pendant I used 22gauge as the base plate so I used a 3M Scotch-Brite abrasive wheel To remove all on the backside and tripoli followered by Zam on muslin on both front and back. Tela, I know how frustrating it gets when something like this happens but it's like your wire wrapping, you have your own style so you don't have to go out and buy from someone else. You can do it just keep trying. I still have melt downs........lol. 39don Thank you. I have lots of designs in my head. I have all the tools and silver, the torch, the rocks, etc but I am so gunshy now. I didn't realize when I began this that the "style" I want, the style in my head is really prone to to the purple stain because of the steps I'm taking and amount of flat sheet showing- if that made sense. Some one on the other forum told me that- it may have been you. I keep telling myself to start from scratch again and see if that helps. I'm sure it will. I think I just jumped in with both feet without enough thought.
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zarguy
fully equipped rock polisher
Cedar City, Utah - rockhound heaven!
Member since December 2005
Posts: 1,791
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Post by zarguy on Dec 27, 2014 0:26:25 GMT -5
Firescale has been my biggest hurdle in learning to silversmith. I find that sometimes I get lots & sometimes little to none. I do the boric acid/alcohol dip & flame trick, but still can't conquer it. I do what some others do, use stamps & oxidation to hide it. Oh and that other thing some do - polish it away. Lynn
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gemfeller
Cave Dweller
Member since June 2011
Posts: 3,786
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Post by gemfeller on Dec 27, 2014 14:18:29 GMT -5
Hi Lynn, do you use a super-saturated mix of boric acid and alcohol? I find you should use every bit of boric acid that will dissolve and try to keep it at that saturation. Also dipping a number of times until there's an even white coating on the piece seems to help me avoid problems. But other variables like torch flame adjustment and heat, type of solder used, torch technique etc. differ from smith to smith. Hope your luck improves.
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