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I created this web page as an addition to the Instrument Care and Repair for Band Directors workshop. It applies more to clarinet and flute repair, but I thought I would post a link here in case anyone is interested.

Inexpensive Homemade Woodwind Repair Tools
Some good ideas here. Only one thing I'd suggest; not everyone has access to drumsticks. But 5/8" (or whatever diameter you like) dowel rods are readily available.
 

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Some good ideas here. Only one thing I'd suggest; not everyone has access to drumsticks. But 5/8" (or whatever diameter you like) dowel rods are readily available.
I've become fond of those chinese-restaurant chopsticks. (Yes, you can even use them as makeshift tweezers to hold tiny (or hot) objects :cool:)
 

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Great post John thanks! Old drum sticks are very useful as I've found for inserting in tenor necks--or bari, when sanding corks.
 

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What about a DIY magnetic dent removal kit? It looks like they are just a tool box, rare earth magnet mounted on some kind of handle, and steel balls. It seems like it would be fairly easy to make if you knew what strength magnet and what size balls to order.
 

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It's not as easy as you think to source all the MDRS stuff yourself. Imagine if you will;

"Good Morning. Acme Industrial Supplies. How can we help you?"

"Oh Good Morning. I need a set of balls."

Good luck.
 

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What about a DIY magnetic dent removal kit? It looks like they are just a tool box, rare earth magnet mounted on some kind of handle, and steel balls. It seems like it would be fairly easy to make if you knew what strength magnet and what size balls to order.
........and where to find the magnets strong enough for the purpose ......... I wouldn't know how to find them........steel balls I have seen them in good hardware stores. Dog Pants, my friend,........this is a tough world........... everybody needs balls !
 

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........and where to find the magnets strong enough for the purpose ......... I wouldn't know how to find them........steel balls I have seen them in good hardware stores. Dog Pants, my friend,........this is a tough world........... everybody needs balls !
There are plenty of different size/shape/strength magnets on Ebay. I don't know which is correct, hence my question. All of the parts should be readily available if you know what is needed (which I do not).

I am sure this one is overkill, but here is an example:

http://cgi.ebay.com/HUGE-Neodymium-...282?pt=LH_DefaultDomain_0&hash=item1c1034e912
 

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I have seen te music medic magnets (the two different sets the normal and the strong one) and another set from another German company which makes repairers items. I just don't know the class of strength of those magnets in order to be able to order an alternative product on line .

In order to be able to use a magnet for undenting purposes you need to coat the magnets with some soft but hard wearing plastic. The diameter of the balls you need, depends on the width of the tube that you need to undent and the size of the dent itself , the size of the balls determine its weight therefore the magnet power that you need. I have seen graduated sizes of steel balls on sale at good hardware shops in Italy, I suppose they would be available at similar shops all over the world.
 

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I'm not sure the magnetic dent removal tools would come under the headings of "Inexpensive" or "Homemade". That might be the topic of another thread however.

I'll share a formula I was taught learning how to do BIR:

The larger and more expensive the tool = the greater damage you can do if you don't know what you are doing.
 

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Apparently the magnets used in the 'Dent removal System' will attract from a distance of 12feet! so yes, these babies can cause a LOT of damage! All I really need is a tool to get at that section in a tenor neck --around the pip-- where nothing seems to reach from either end.
 

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I have seen and handled these magnets at the Frankfurt show ...........they are nowhere near as dangerous as most detractors will have you thinking and there are no scissors , screwdrivers and knives flying about in their vicinity (12 ft empty space around them......yeah right ....... you should see how big is Music Medic booth at the Musikmesse! :) )and possibly there were people with pacemakers walk by without falling dead. the only way that I could think you could hurt yourself with them if you hold any of your bodily parts (let your imagination run free) in between them at a distance of 10 cm and then you let go of one .........seriously, like every metal tool ca be dangerous and you don't want to keep it close to a card with a magnetic strip but these things are not too dangerous.
 

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Apparently the magnets used in the 'Dent removal System' will attract from a distance of 12feet! so yes, these babies can cause a LOT of damage! All I really need is a tool to get at that section in a tenor neck --around the pip-- where nothing seems to reach from either end.
I have the magnetic dent removal system, and also import/sell similar size/strength magnets as a sideline job. These magnets sure are dangerous for damaging fingers and clothing - equivalent to holding your finger on an anvil and smashing it with a good size hammer. (That is if there are no sharp edges involved!) But the field strength (hence pull) reduces rapidly with distance. At 15 cm, it might lift a paper clip, or I might start to feel pull towards a vice. At 20 cm, not a hope.

So don't believe all you read. :) I suppose the suppliers have to protect themselves from litigation.
 

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........and where to find the magnets strong enough for the purpose ......... I wouldn't know how to find them........
There's a big range at this reputable source. http://www.kjmagnetics.com/categories.asp

The largest, strongest MDRS ones are around 50 mm diameter by 50 mm long (2" x 2"). The grade of magnet is at least N45.
eg http://www.kjmagnetics.com/proddetail.asp?prod=DY0Y0-N50

Yet even this size struggles to get dents out of the toughest sax body metal.

This is an interesting magnet calculator, that shows pull and field strength:
http://www.kjmagnetics.com/calculator.asp
 

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Thanks Gordon great stuff!
Correct me if I am wrong. My understanding of the un-denting magnets is that you don't really need the magnet to be strong enough to withstand (through the horn's body wall) any " pulling" action. One ideally just moves the magnet and the ball inside follows the magnet around burnishing the dent until it is flattened. Indeed, I remember Curt specifically advising against exerting any outward forces as this could create striations So the magnet has to have a force just sufficient to pass through the metal wall of the horn in question and counteract the weight of the ball, not more than that (as it would , indeed, be necessary if one would actually " pull" the dent out). That is what I have understood from having seen several demonstration of the magnets.
Hera a couple of videos, one by Sonofjabba who is also a member here on SOTW, perhaps he could chip in and advise on the how and where to find the magnets in question and apparently he has the balls! :bluewink:, see also that he uses a piece of hard plastic (and some spray which I assume is some oil of some sort) to protect the horn from excessive scratching against the magnet metal.
 

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Milandro, the bottom 3 videos (edited for clarinfication)appear to be using the standard MDRS system as supplied by
http://www.magneticdentremovalsystem.com/
If you were to manufacture one yourself, you would need a magnet approx 1 inch plus in diameter with a minimum field strength of 300 gauss at the surface, your not pulling the dent out, merely rolling it out with the magnet being used as the backup surface
I have no problems removing dents out of sax bodies with these units as supplied from the company above
Field strength is still active and strong at 1-2ft, after this it dimishes quickly
The spray would be just furniture polish, so it glides a bit better, and the plastic is simply drum tops to protect scratching of the instrument
 
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