EMG fiber needle container

[clipper]

Having just read the most interesting link given by Orchorsol, on the making and possibly doping bambboo needles, I was surprised to see that under various 'recipes' there was no mention of using Chromic Acid.
I have not myself done this for a good many years, as the gramophones have 'till recently been out of use, but I did find that by pickling for a few days in in chromic acid had a decidely beneficial effect, the needle points holding up well in loud passages.It was also easy to judge the state of pickle by the change in colour. The needles were then washed and of course thoroughly dehydrated.
I cannot claim that the idea is original to me, as I remember reading about it many years ago.... but where I have completely forgotten.

[Orchorsol]

Having just read the most interesting link given by Orchorsol, on the making and possibly doping bambboo needles, I was surprised to see that under various 'recipes' there was no mention of using Chromic Acid.
I have not myself done this for a good many years, as the gramophones have 'till recently been out of use, but I did find that by pickling for a few days in in chromic acid had a decidely beneficial effect, the needle points holding up well in loud passages.It was also easy to judge the state of pickle by the change in colour. The needles were then washed and of course thoroughly dehydrated.
I cannot claim that the idea is original to me, as I remember reading about it many years ago.... but where I have completely forgotten.

Very interesting to hear that you've tried that treatment and found it effective. What concentration of chromic acid did you use?

[clipper]

My use of chromic acid was not terribly scientific; I merely used stock solutions that I had in my darkroom for bleaching bromoil prints ready for inking, or intensifying under-exposed negatives.
The mixture was always made in two separate solutions and mixed in equal quantities for use.

Solution A Potassium bichromate......1 oz
Water ............25 ozs


Solution B Hydrochloric acid.........½ oz
Water ...........25 ozs

The soaking time is really an unknown quantity, but if I remember 24..36 hours seemed to do the trick.

[Orchorsol]

My use of chromic acid was not terribly scientific; I merely used stock solutions that I had in my darkroom for bleaching bromoil prints ready for inking, or intensifying under-exposed negatives.
The mixture was always made in two separate solutions and mixed in equal quantities for use.

Solution A Potassium bichromate......1 oz
Water ............25 ozs


Solution B Hydrochloric acid.........½ oz
Water ...........25 ozs

The soaking time is really an unknown quantity, but if I remember 24..36 hours seemed to do the trick.

Many thanks, Clipper! I wonder whether other oxidising solutions would have the same effect, or whether the chromic acid mixture is in some way unique.