cleaning brass after soldering

The exothermic reaction argument is a bit of a canard, as the video shows.

If you pour water into a container of battery acid, any splashes will be more concentrated than if you poured the acid into the water.

Regardless of Tim's comments, I'd rather not splash acid at 'battery' type concentrations if I can avoid it, at the very least it ruins your jeans ...

Pouring small amounts of water down a narrow filler into a battery is unlikely to cause splashes, because of the design.

Neil

Acids and products containing them may well become more difficult to obtain in the none too distant future.

There are a few online petitions on the go, the one with most signatures (I think) 350K+, is calling for registration and/or licence to purchase acids

Also the Westminster Politicians are due to discuss acid attacks later this month.

When the politicos get involved, that does not bode well for legitimate users such as hobbyists etc, of course what is likely to be forgotten in all this is that the bad guys will just find another way.

Edited By V8Eng on 10/07/2017 21:47:06

TBH, I wouldn't object to signing for acids if it helped stop the attacks.

Once upon a time we all had to sign the 'poisons book' to buy anything interesting.

Neil

Sounds like a very sensible policy, but with the advent of purchasing things so easily online I just wonder how well it could be enforced, It's at least another hurdle I suppose.

To be honest, the types of people who would consider this wouldn't put themselves beyond using the dark net, however, that place is also crawling with law enforcement and surveillance and traps designed to waylay the criminals, a lot of potential terrorists have been caught this way.

And even spend too long on there and you'll probably get the famous knock at the door even with an IP mask.

Michael W

It's always the legitimate user who gets stung. But then if nobody abused the law there would be no need for this. The inevitable result of the abuse is simply more and more rights being taken away from people, it's as simple as that.

Michael W

If you look in the right places it is amazing what you can buy. Amazon sells some pretty horrific chemicals including sulfuric acid!

The problem with most of this type of thing is that knee jerk laws are put into place which simply do not work, but fool people into thinking something will be achieved by it.

Knives cannot be sold to young people but knifing seems to be almost routine in cities, often by those people too young to buy knives.

Very similar thing with the bans on gun ownership, they still seem to get used routinely for crime.

Make the purchase of acids more difficult and they will just get it underhand or find something else to use instead, but buying something to clean brickwork or to assist in boiler making might well get the attention of an anti terrorist official, and maybe even the 2am knocking down of your door.

Edited By V8Eng on 10/07/2017 23:45:45

A solution of caustic soda in water (always add the caustic to the water folks, you've been warned!) cleans up HT5 flux. Fortunately this dangerous chemical can still be had at your local Wilko. It's good for unplugging drains too.

Rob.

Out of interest, what would be the effect, if any, on the bacteria both aerobic+anaerobic, in a 2000litre septic tank of using a caustic soda solution for pipe cleaning ?

DaveD

To offer Meunier an answer:
There would be a change in the pH* of the liquid, and those critters which could stand it would do better at the expense of those which couldn't. How many of either sort were there, would depend on what else has been sent down the pipes recently. The wildlife of a tank where there are children will be different from one with pensioners, and both will especially be different again from one for a holiday home, empty in the winter.

*pH is a fancy scientific measure of the acidity or alkalinity of a chemical. The figure ranges from about 1 for really acid solutions to about 14 for really alkaline ones. Plain old water is about 7. I can't remember how it is calculated, but I think logarithms come into it. Not that anyone under about 50 will know what logarithms are, I suppose.

When I worked in the chemical industry (long ago) a colleague explained that whatever chemical you were to tip away, if you did it regularly, something would eventually colonise it and use it as a resource, turning it into something else. After all, life started (we think) in the plumes of noxious chemicals billowing from underwater volcanic vents.

Thanks, Tim, pretty much what I had assumed and since they have been happily slurping for 18yrs without problems and still pass the 4-yearly inspections I will leave them undisturbed.

p.s if one were building a Napier diesel or aero engine would logarithms be useful ?

DaveD

With apologies to the OP and his question about flux:-

Foregoing postings illustrate a variety of personal perspectives on risk assessment of chemicals.

(risk = hazard x exposure e.g. high hazard + infrequent, low exposure means low risk and vice versa).

Major part of lifetime's work was in the heavy chemicals industry with much time spent on risk assessment. May I therefore recommend a little (amusing?) reading on handling of conc. mineral acids and explosives in times gone by?

**LINK**

Why the one-legged stool ? To prevent him falling asleep on the job !.