On Sun, 23 Oct 2016 11:04:05 -0700 (PDT), robobass
wrote:

I make an unusual product (www.basscapos.com) which must be polished to jewelry standards, but includes a 5/16-24 threaded brass stud which is soldered to a brass bar. Torch soldering naturally produces firescale, which is hard to remove from the threads. There is a very effective product to combat this called Cupronil. You first preheat the work to maybe 600°f and then spray it on. It leaves a coating which protects the part. Works wonderfully. Problem is, I am going through it like mad. I have tried a bunch of different pump spray bottles, but none give me a nice focused spray pattern so that I don't waste the bulk of it. It wouldn't be such a problem if I could buy it in my country (Germany), but I can't. I suppose I should invest in an airbrush. I have a compressor, but I like the simplicity of a spray bottle, and the airbrush would still involve some experimentation to get it right. Can anyone think of an application where a precise pump spray bottle is used and easily
available? Cupronil seems to be similar in viscosity to water, but it is enough different that a bottle which gives a perfect spray pattern with water isn't very good with Cupronil.

Thanks!
We have available here in the USA spray bottles made for spraying
vegetable oil. I'm sure Germany must have them too. They are
pressurized by pumping air into them with the cap. Then you have a
pressurized spary, not a pump. The pressure can be regulated by how
much air is pumped in. When the pressure drops the spray is pretty
weak and doesn't spread very much when used with olive oil.
Eric