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Re: Nitol .....and List Exodus

In a message dated 15/09/98 06:24:28 BST, you write:

<< I posted a question about etchants that never
 made it thru, I don't know why, but apparently there is
 little interest in "newby" questions here. Well, here goes:
 is there a substitute for Nital that I can buy or make
 myself? I just acquired a 600 gr. piece of Gibeon (a
 meteorite I could afford) and it needs to be re-etched. It
 also has a small amount of rust, any ideas as to the best
 way to remove it? >>

Brian,

Some of our pleas for help and assistance often get overlooked while there's a
List arguement in progress....as I've often discovered! Persevere with follow-
up posts until someone stops and responds.....in a loud voice if necessary.

I'm not sure that there's a reasonable alternative to a nitric etchant mix,
but there was some mention of trying ferric chloride (PCB etchant) a few weeks
ago. This stuff stains everything it touches, so I'd not recommend it's
use.....anyone know any different?

If your Gibeon isn't too badly rusted, you can try this method for removing
THIN rust stains, rusty cracks etc. Use a **soft** pencil eraser to gently
rub-out the rusty blemishes on etched faces - it's a semi-permanent cure that
at least delays the need for a complete re-polish and etch. Be sure to work
only on the rusted portions, and avoid wandering too far onto good etch parts.
For a complete face-lift, this also works quite well for removing tarnish
across the whole etched face of un-protected irons (deeply etched specimens
only!), bringing back the lustre that has been lost with time. I've also used
it to good effect on freshly etched coarse octahedrites, to remove the dark
sulphide stains that were probably caused by my % of nitric being too high
when first mixed. If you try it, I stress a **soft** eraser, and **gentle**
action.

If the rusting has taken a good grip, then you could try carefully removing
small areas with the point of a scalpel blade before using the pencil eraser,
but by this time it's usually preferable to re-polish from about 240 grit
through to 1200 grit abrasive papers, re-etch, rinse, neutralise & thoroughly
dry the specimen. The post-etch stages seem to be an art in themselves, with
many differing and favoured ways asserted in previous postings, so I'll not
rock the boat with my preferred methods at the moment!
Hope this helps.

To those that have recently left the List in anger or frustration (assuming
you're still here to read it):
There are over 300 people on this List from all corners of the
World.....different ages, nationalities, varying degrees of expertise/genuine
interest in meteorites, different sense of humour levels (don't I know
it!!)....and probably more crucially.....different personalities!
With so many variables, there's not much chance of us all living in perfect
harmony all of the time. I've had a few blunt, rude or otherwise obnoxious
emails sent to me in the past, but choose to ignore them. Try doing the same,
because if you leave, you'll be sadly missed by the vast majority of us.

Best wishes from Scotland,
Rob.
http://hometown.aol.com/fernlea4/index.html

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