View Full Version : Finish on Old Waterhouse Stops?

Colin Myers
31-Mar-2007, 08:41
Does anyone know what the, original black finish was on old Waterhouse Stops?
These were mainly manufactured from brass. Would Oil Blacking work, or is there another chemical process one could use to re-black them?
I would be most grateful for all input.
Colin Myers

Jack Flesher
31-Mar-2007, 09:18
I'm not sure what the original was, probably kerosene lamp black which is messy. These guys have a bunch of products that may be suitable -- and I know you can buy them in smaller 2-4 ounce containers: http://www.birchwoodcasey.com/store/antiquing.html

Edit: Found a 3 ounce jar of "brass black" -- have to go to "blueing" on the top bar, then scroll down about half way: http://www.birchwoodcasey.com/sport/index.html


Ole Tjugen
31-Mar-2007, 10:28
Another nice trick is to clean the brass well, then tone it in strong Viradon (or any other polysulfide toner).

Alan Davenport
31-Mar-2007, 10:53
Brass blackeners are commercially available; check gunsmithing supply shops. They are generally selenium based, so you could probably use a selenium toner to achieve the desired result also. You'll also need muriatic (hydrochloric) acid to prepare the brass before blackening.

31-Mar-2007, 11:23

I found this in a little old book - ABC Guide to Photography - no date, but it looks like it was published about the time dry plates became popular as it mentions the 'old "wet plate" days' in the text a few times.

Brass - to Blacken

The amateur often requires to re-blacken stops of other portions of the brass works of his apparatus, which have seen considerable use. The old black should first be cleaned off with a piece of fine emery cloth, and the metal should then be dipped in a mixture of equal parts of the following solution:-

No. I. Solution.
Silver nitrate..... 40 grains
Water..... 100 minims

No. II. Solution.
Copper nitrate..... 40 grains
Water..... 100 minims

When the stops are removed from the above solution they should be allowed to dry, and should then be uniformly and gradually heated until they assume the desired black colour.

1 gram = 15.4323584 grains.
I'm guessing a 'minims' is a drop.


Ole Tjugen
31-Mar-2007, 11:28
The acid is to reduce the zinc content of the exposed metal, so that you get a coating of copper selenide (or sulfide). Copper sulfide is both harder and darker than zinc sulfide, so you get a much better result.

Don't overdo the etching, though - and wash it properly between etching and blackening!

Ernest Purdum
1-Apr-2007, 09:39
It's interesting to note how many materials, and particularly chemicals, were readily available in the early days of photography but much less so now.

Ole Tjugen
1-Apr-2007, 09:47
1 minim (US, liquid) = 61.61 cubic millimeter - or 0.00006161 liter, or 1/480 fluid oz (US). An Imperial minim is a bit smaller, 59.194 cubic millimeter. :)

Colin Myers
1-Apr-2007, 12:19
Thank you everyone for your various solutions, now spoilt for choice.
I will have to mull over these and decide which looks to work best, also availability of materials. Many Thanks
Colin Myers

Jim Rice
1-Apr-2007, 18:05
A good hobby shop will have it in reasonable quantities. Model makers use it.