TubeNet

Here's a question for you repair guys. I saw some videos on Youtube of dents being removed with a magnetic dent ball. I have heard of this but have never seen it done .
As ususal for Youtube the video quality was poor so I am unsure about a couple of things . The whole procedure took only a few minutes to remove several severe dents but it looked brutal . Does this scratch the finish of the horn ? Are the dents perfectly rolled out so you can't tell they were there . How the hell does it do work ?

T.Y.

I am not a professional repairman... just a rural band director. I have used the "Dent Eraser" extensively so I can tell you some things about it. The process is very fast, as you observed. It works by magenetic attraction. The steel ball goes inside the horn at the location of the dent. Then you apply the very strong magnet to the outside of the horn. The magnet attracts the ball and the brass in between is flattened (un-dented). It does not produce perfect (can't tell it was dented) results, but for beat up old school horns it is quite impressive. There are fuzzy (think soft side of Velcro) pads to reduce horn scratching, but not completely prevent it. I spent acouple of hours on the 10 tubas and baritones we have and removed the largest of the dents. I could have sent them to repair and spent beaucoup dollars to get the same results, even more to make them flawless.

But bear in mind... I will not use it on MY horns.

oldbandnerd wrote: . . . . dents being removed with a magnetic dent ball. . . . . Does this scratch the finish of the horn ? Are the dents perfectly rolled out so you can't tell they were there . How the hell does it do work ?
T.Y.

A dent eraser is not perfect, but is handy for removing medium dents from bows and other not-too-thin locations. However, it creates obvious furrows and ridges which may be nearly impossible to remove from large, open surfaces, especially where the brass may be thin.

See the link below for one previous discussion:
viewtopic.php?t=19863&highlight=dent+eraser

Ferree's Tools on Magnetic Dent Removal
http://www.ferreestools.com/magnetic_dent_tools.htm

I am not a professional...BUT....I have worked for a pro repair guy and have taken many many dents out of tubas, baritones, euphs, and esspecially SOUSAPHONES using magnetic dent balls. The one way that I use is that I start with the smaller tubing dents, using the right size ball, and work towards the bell end of the horn....gradually increasing the size of the ball as the tubing increases to NOT MAKE any ridges or more dents. The guy I work for has some balls up to 6.5 inches in diameter for the large tuba/sousa branches.
Also...
Take a terry cloth towel, double it over, and put in on the magnet to prevent scratching.
To start, place the ball behind a ferrule, and use all your strength to slowly bring the magnet to the horn, as to not dent it there either.
Just some thoughts...
Blake

I pounded a softball sized dent out of a souphone bell arc with a rubber mallot and a bag of lead shot on my kitchen counter. Worked very good.

Funny, there's a repairman in Tyler who'd invented the magnetic dent remover. When, who was it, UMI(?) first came out with the kit for sale he was sure someone had let his secret out. He called appropriate people and found that indeed, someone had followed the same path he'd followed in developing the kit but they took it to market before it occurred to him.

As to the quality of work, he was able to remove all traces of dents in a lacqured Conn 3-J with no malforming of the tubing and no tracing in the lacquer. He did not limit his in-the-tube dent work to only dent balls but I'll leave it at that.

BAT boy wrote:I am a pro

...good for you...

BAT boy wrote:but to a band director or some schmuck that bought a dent eraser good luck. I have repaired quite a few "repairs" from schmucks with dent erasers.

I'll thank you that I am a band director but I am no schmuck. I think my non-disassembly repairs are quite comparable to a shop job. I can solder and true tubes. I can unstick slides and mouthpieces and repair valve stems. I can replace springs and patch holes. I can repair and paint fiberglass.

But I still will not use a dent eraser on my horns.

Good tools. I use my magnets and balls about every day... but... NOT for everything.

bloke wrote:The closer the kit's spherical ball (or substitute egg-shaped dent ball) is to the size of the bore of the tuba at that point...AND the stronger the wrist of the user, the better the job. bloke "The Dent Eraser can quite easily be a Dent Creator."

A little silicone lube spray can make things a bit easier...

harold wrote:

TubaTinker wrote:Good tools. I use my magnets and balls about every day... but... NOT for everything.

Hate to be Mr. Obvious again, but Dan's post is dying for some color commentary.

Up to the challenge Doc?

It looks like, after reading the discussion on this thread, that dent balls are no different than any other tool: a good tool, which has its place, which must be wielded with care by a person with proper training, in the proper context. In that regard, it is just another tool for specific jobs -- not a "cure-all," not necessarily a substitute, possibly good in the hand of a good amateur (from a repairman's perspective) to get through an emergency situation; a good addition to a workshop that already has the appropriate array of other bench and hand tools. Finally, like any other tool, as a torch or a hammer, something that can completely damage an instrument if not wielded correctly.

"wielded"

Yeah -- caught and fixed.

OK -- all together now:

"I before E except after C
Or when sounded as A
as in neighbor or weigh"

iiipopes wrote: OK -- all together now:

"I before E except after C
Or when sounded as A
as in neighbor or weigh"

That's not a very scientific rule, is it?

Chuck(G) wrote:

iiipopes wrote: OK -- all together now:

"I before E except after C
Or when sounded as A
as in neighbor or weigh"

That's not a very scientific rule, is it?

I don't know -- it seems to work on single syllable words.

iiipopes wrote:I don't know -- it seems to work on single syllable words.

Well then, sir, I suggest we hoist a stein or two to celebrate this discovery. To do otherwise would be the height of folly!

It's weird--I'm gettin'a headache over this rule stuff, but a little codeine ought to blunt the pain...

"I before E
Except after C,
Unless pronounced A
As in 'neighbor' or 'weigh'"

Education is forfeit for reinforcing such rules!
Sound a feisty reveille while eyeing the schools!
Neither will our heirs be agreeing to deceptions
Once seeing, herein, these sufficient exceptions:

We were seized by a feeling
For fleeing on the ceiling
To a leisurely meal
With Keith, Sheila, and Neil

We drank madeira, so foreign, in steins
Along with a surfeit of weird blueish wines
Being foolish, took codeine, ate ancient proteins
Therein guaranteeing these ogreish scenes

Wherein we're canoeing to a new sovereign state
While deicing a kaleidoscope on a hot jadeite plate
And kneeing obeisance to an overseeing king
Our plebeian lips kissed his counterfeit ring.

Then we unveiled their sleight-of-hand trick
Deifying a heifer, with effect atheistic
And falling from the heights with a loud seismic crunch
We reignited the nonpareils we had heisted for lunch.

So I before E
Except after C
Unless pronounced A?
False decreeing, I say!

©1995 by Jef Raskin
It contains, I think, 51 exceptions to the usual rule.

As I have said on another thread, if I didn't say it the way it really was, I'd get skewered. I have just been skewered. Now I'll have to console myself, being the outdoor concert season, with my souzy and a few break strains to a few good marches.

bloke wrote:Another thing for which we must be cautious is the combination of magnetism and spheres...

Yeah.... and you gotta be careful not to get your fingers between the magnet and the ball. Even worse... fingers between two magnets! Yikes!

iiipopes wrote:As I have said on another thread, if I didn't say it the way it really was, I'd get skewered. I have just been skewered. Now I'll have to console myself, being the outdoor concert season, with my 38K and a few break strains to a few good marches.

Ah, but it's skewering, I trust, among friends, no? That's the best kind!