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Need alume


jdm

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I'm assuming you made a minor spelling error and you're looking for Alum?

So personally the Wikipedia entry is almost confusing is lots of variations lots of variations of uses. The bottle I have is residing in the kitchen because it was used for making pickles. Strangely enough the bottle looks more like something from the drugstore and the labeling Ammonium alum astringent styptic Definitely implies medical use. As the Wikipedia entry shows it has lots of interesting uses. My personal favorite use of it is very concentrated solution in a Pyrex container that I can heat up on the stove to dissolve iron or steel screws out of brass.

https://en.wikipedia.org/wiki/Alum

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Actually Vinn, it's a little known trick, Potassium Aluminium ...sulfate? (i forget the full name) chemically corrodes steel over a long time (which comprises most screws and stems) and leaves stainless steel and some other metals perfectly intact. Useful if a stem has snapped off flush with the crown and there's no way to unscrew. Funnily enough I only know about it because of this forum when I asked about Visin which is a more potent but more expensive and hazardous means to the same end.

To answer your question JDM I found some on Amazon, under a food department as it's added to bread to whiten it. 

Edited by Ishima
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So googling says it can be found in the spice rack of places selling cooking supplies. The indication is it's hiding hard-to-find my experiences spice racks are usually not alphabetical it's probably towards the bottom. Other places Chinese drugstores? Out of curiosity I was looking at Boots Which does have online where I could search two items were revealed. One of them appears to be it's probably in it somewhere the other one said it was Alum powder extremely promising except it needs prescription?

Then a course there is online.

https://www.amazon.co.uk/Anti-Bacterial-Deodorant-Fatakdi-Potassium-Sulphate/dp/B00C77ZSSS

Then for the next link minor thing that's bothering me when you look up Alum and the link below shows this comes with a variety of chemistries I wonder if there's any difference for what we want to use it for?

http://chemistry.about.com/od/moleculescompounds/f/What-Is-Alum.htm

 

alum.JPG

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1 hour ago, frenchie said:

Potassium Alum is for sale on the bay and at the retailer with the name of the longest river in the world

The last place I got around the searching was eBay. I would definitely recommend looking here first scrolling down the images titles gives you an idea what you're looking for if you want to look for in your local stores otherwise more than likely somebody here can sell it to you.

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Bought 1Kg for €8 from specializing drugstore. Local watchmaker quoted €30 for the the job, which is reasonable but I wanted to try myself. Whoever wants some for free just PM. 

Now wondering for how long I should keep it heated during the process.

Edited by jdm
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I don't know if there is an official procedure written down? So for me it's mixup as strong of a solution you can get apply heat to the point where it's boiling, Or very close to boiling. They do have to watch it as it will dry out. Which is not really a problem just add more water. As I have it on the stove I usually have it in a Pyrex container in a regular stove pot that has water so I don't have to worry about something bad happening with alum getting all over the stove. Although I did break a Pyrex container once because the whole thing dried out so you really do need to pay attention to it and not wander off.

So when it's working you will have little bubbles coming up from the steel part. I really can't remember how long the last one took it's been quite a while. So basically the stronger the solution the hotter it is the faster it works.

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