FORVM`s Classical Numismatics Discussion Board

Numismatic and History Discussion Forums => Uncleaned Ancient Coin Discussion Forum => Topic started by: Ken W2 on September 08, 2020, 03:11:41 pm

Title: If at first you don't succeed (abrasives part two, dremel rubber and felt bits)
Post by: Ken W2 on September 08, 2020, 03:11:41 pm
Hello all:  I've given up on Prelim for removing cleaning marks.  It doesn't have enough abrasive quality to efficiently remove scratches and is heck to clean out of the crevices.  Below is a bf and after of a City Commemorative, Roma/she wolf type, which cleaned up pretty nicely imho, showing the type of cleaning marks I want to smooth out. These are light scrathes in the patina that do not go to the metal itself.  Obviously, the danger of further work is I might get to the metal.  Since taking the after photos I have used used a black nylon brush in a dremel under running water which removed a little more dirt and I think smoothed some scratches.  I am now considering using a fine grit rubber polishing point in a dremel and/or the felt/wool polishing points.  I tried the felt on a discarded coin and it definately helped some.

So, has anyone used the rubber or felt points in a dremel for this purpose ?  Any advice-- under water, dry, courseness of the bit, just don't do it, etc ?  As always, I welcome the input of all.

Ken       
Title: Re: If at first you don't succeed (abrasives part two, dremel rubber and felt bits)
Post by: Mark F on September 10, 2020, 09:46:42 pm
Ken,

I've used very fine rubber polishing bits (made for jewelry work, I believe) on coins before, but only by hand and not using a power tool. I just mount one in a pin vise. Have used several shapes from very pointed to more rounded. Works pretty well sometimes when I don't want to use a scalpel blade for removing the final traces of dirt on a surface. I just scrape with it or make very small circular motions to dislodge the smutz. Very similar to using a fiberglass pen, though the rubber is a bit less likely to remove patina. I've never tried the wool points you mentioned, but those might be even more gentle than the rubber I've used.

I think your coin is nice and lovely. Good work!

Mark
Title: Re: If at first you don't succeed (abrasives part two, dremel rubber and felt bits)
Post by: Ken W2 on September 14, 2020, 02:09:51 pm

Thanks for the response Mark.  This week end I experimented with fine grit flame shaped rubber polishing points under water and dry, as well as wool/felt polishing pads using different grades of polishing compound.  Both helped with removing some scratches, but neither removed all. Also because its such fine detail work it is hard to keep from rubbing through the patina at the highpoints of lettering and design features, especially with the wool/felt pads.  The flame shaped rubber points worked best removing scratches and avoiding high points, but they too left scratches visible at 10X under my micrscope.  I've ordered some extra fine grit flame points and will give those a try when received.  Also just received some fairly pointed wool/felts pads and will try those.  I'll keep experimenting on slugs or semi-slugs before trying to dress up what I consider to be better coins, like the one pictured.  (That's 8-9 hours of work I don't want to foul up.).

I think I understand now why others have been hestitant to join in this discussion and give advice. This stage of cleaning/restoring/finishing is quite difficult.  When you've cleaned a coin for hours without breaching the patina and exposing metal, is it best to live with cleaning scratches or risk polishing through to the metal in an effort to improve the coin ?  I'm leaning toward the former (and will just learn to clean better!!!), but I haven't completely given up on abrasives yet.  Will share some photos when/if I find an approach which yeilds the desired results.

Ken       
Title: Re: If at first you don't succeed (abrasives part two, dremel rubber and felt bits)
Post by: Justin W on September 14, 2020, 02:39:07 pm
Ken I think the scratches are a part of the process and in my opinion it’s best just to leave as is (however frustrating that may be). I love the cleaning process but when I’m done with my coin I’ll either flip it or wax and flip, usually leaving scratches as is.


Best Regards,
Justin
Title: Re: If at first you don't succeed (abrasives part two, dremel rubber and felt bits)
Post by: Joe Sermarini on September 14, 2020, 02:59:02 pm
The best thing to do is to clean coins under a binocular microscope with a soft touch that does not leave scratches - at least not scratches visible to the naked eye. I have slipped under the scope and cut through to bare metal. It is horrifying but take it out from under the scope and you can't see the scratch at all.