
Repairing a dented tuba with magnets - mixmax
http://www.supermagnete.de/eng/project8
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JonnieCache
I'm sorely tempted to order one of their super-strong magnets, such as
<http://www.supermagnete.de/eng/K-26-C> but I'm almost certain it'd lead to
personal misfortune.

I wonder if this one of those "regret the things you do, not the things you
don't do" situations, or simply a "don't be an idiot" situation...

EDIT: Just seen this one. Bloody hell.
<http://www.supermagnete.de/eng/SALE-038>

Also interesting, this page <http://www.supermagnete.de/eng/faq/price> about
how the price of neodymium "increased about fivefold between January 2011 and
June 2011" due to china reducing export quotas.

~~~
dzuc
Really: be careful. Strong magnets are extremely dangerous. I once managed to
get a 1" cube of neodymium stuck on either side of my hand for a few minutes.

~~~
mikiem
Think this is the very first thing anyone does when handed two pieces of
neodymium. I know that I did this within a minute of my first experience with
two free and loose neodymium magnets. I watched many others do it too. The
look on one's face is always of shock and disbelief that this magnets were so
strong, mixed in with the pain, even though you warned them before.

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phaedrus
The striking thing about this is not just that it _works_ but that it works
_so well_. That I did not expect.

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mrkurt
Wow that beats the heck out of disconnecting the joints, rolling it out by
hand, and then soldering everything back together. That would have saved me
hours in high school. Plus, magnets.

~~~
darklajid
I guess it's not only a time saver. Unless you actually would unroll/re-solder
an instrument worth > 10000 EUR, which would scare the hell out of me.

Funny trivia: The article uses ' as delimiter here, as in 10'000 although
Germany (the domain name uses .DE and the company is based there) uses the .
here -> 10.000 Seems like the author ('from Italy') of that post is using the
swiss notation? Any other (european) country using ' as a thousand separator?

~~~
bsk26
I worked in a music shop during high school and pulled apart a few tubas worth
at least that. We had a similar magnet tool, but it didn't always work
perfectly, and could leave scars in the metal if you weren't careful. His tool
might be better, or he might have gotten lucky.

We certainly didn't try to unroll them, however, and I let my mentor solder
them back together.

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phil
That's very clever. Their "reverse hammer" is reminiscent of the climbing
world's funkness device:

[http://books.google.com/books?id=vNyk_tSE2mUC&lpg=PP1...](http://books.google.com/books?id=vNyk_tSE2mUC&lpg=PP1&dq=big%20walls%20book&pg=PA23#v=onepage&q=funkness&f=false)

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zck
That reverse hammer is fascinating. I'm a little confused by the diagram,
though -- I think the magnet stays on the instrument's surface for the entire
motion. It never comes away from the instrument, even after the hammerhead
hits the stopper.

~~~
fr0sty
It is called a slide hammer. The blow to the end of the shaft is transferred
to the magnet on the opposite end and pulls the magnet inside.

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MJR
Very cool. I talked to a few of brass-playing musician friends and this is the
standard process for getting rid of dents in brass instruments.

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BuddhaSource
They use a similar techniques to repair dents on your car.

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hippich
Too bad they do not ship to USA. Any clue why this could be? Because of
magnetic field and air shipping?

Also, any clue where I could find something similar in USA territory?

~~~
mixmax
I just ordered a few magnets from their site, including one that can lift 100
kg. (<http://www.supermagnete.de/eng/FTN-63>) and worried about the exact same
thing.

There's a shipping guide on their site, and apparently it's not as problematic
as you would think since you can "shortcircuit" a magnet by wrapping a piece
of metal around it. The guide is here:
<http://www.supermagnete.de/eng/faq/shipping>

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iwwr
Can this be used to repair bent car body panels?

~~~
mrtron
The magnets would have to be so strong they would be dangerous to work with.

The easier way is just weld rods on to pull a dent out with, and then chop the
rod off. There are several dent pulling tools that work this way.

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masterponomo
In England, we don't dent the tuba.

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rhdoenges
Wow, that is a nice tuba.

