Whoo hoo! It's not bulls*** - removing broken taps

[Peter S]

I just got a new book from Lindsay - "A Day at the Factory".

It was originally written in the 1840's, and was a series of articles published in a weekly magazine that aimed at enlightening the layman about how things were made etc.

These articles are all about visiting various industries and factories and explaining how they made things.

One of the chemical factories is making alum, and there is an illustration of this huge eery opaque sort of crystal about 2 metres high.

It explains how this was done, and one or two new and improved methods.

The descriptions don't give exact details or specific amounts, just general methods and ingredients.

Very interesting book....but it has been borrowed by a friend already, so that is why I am sounding vague on how they made alum...

[Wirecutter]

Yeah, I don't know about the various purities of alum, but the stuff I got from the crunchy-granola place in California is what I've been using. I can provide the name of the place if anyone's interested.

I had one tap broken in the edge of a 1/4" aluminum plate. I used the dremel to drill a very small hole at a 90-degree angle to the bottom of the hole I was tapping. This allowed the solution to get into the hole. It's true that bubbles and such can block the reaction, and drilling a hole sped up that particular one considerably.

As for using a battery charger at the same time - I'd want to do that outside at the very least. There are other posts here about the battery charger "derusting" process - you have to be careful about the materials involved. Salt (NaCl) for example, is a bad electrolyte ingredient because the reaction creates clorine gas, and presumably sodium, as well as probably hydrogen gas. Stainless steel used as an electrode is bad news because you get chromium in the electrolyte, and that creates a hazardous materials situation. When I did the derusting thing, I used OxyClean in the electrolyte (for it's Sodium Carbonate content) - the resulting bath can be flushed down the drain.

The idea of a wax "dam" around the area in question sounds interesting, though.

[MikeG]

about 40 plus years ago when I was stationed at Keesler AFB in Mississippi. we would have a "barracks barber". At the time I wore a flattop haircut, wet hair, apply a solution of alum and water, comb hair, let dry. it's like cutting timber!

MikeG