Dent removal

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ThomasDodd
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Dent removal

Post by ThomasDodd »

Man, I have a new respect for the brass techs now. I spens an hour or so yesterday working on the outer bow of my horn. Got the easy to reach spots, but that's only 1/3 of the work needed. It ain't pretty or smooth yet, but it's mostly round :)

I understand the labor charges for this stuff. Now soldering and other work isn't too bad, say $25 -25/hr, but dent removal like this is easily worth $80/hr.

-Thomas
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Chuck(G)
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Post by Chuck(G) »

Maybe so--but it's the cleanup that I hate. Consider that taking the dents out of a bottom bow usually means removing the bow from the horn, stripping the lacquer from the bow, unsoldering the cap and wire, removing the dents from all parts, cleaning the parts up, resoldering everything together, cleaning up the excess solder, reattaching the bow and cleaning up the solder around the ferrules and buffing the whole affair nice and shiny, then relaquering.

Scraping, buffing and ragging can take much longer than the actual dent removal.
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ThomasDodd
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Post by ThomasDodd »

Chuck(G) wrote:Scraping, buffing and ragging can take much longer than the actual dent removal.
Still, that while time consuming, it isn't as much physical labor. The pieces aren't heavy and buffing it wouldn't be hard work. Long process sure, but not as physical nor is the same level of "craftsmanship" required. (One of the problems I'm having with auto body work is the artistic element. I can sand, clean and fill no problem. But matching the curves is giving me fits, especiall the compound curves )

But I'm not even worried about that. :)

The lacquer is so bad now, it's not worth it. And I wouldn't ask anyone to polish this horn.
I'd hope any horn worth polishing and relacquering would be taken better care of.
Of course disasters do happen... :(
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Post by Dan Schultz »

ThomasDodd wrote:[

Still, that while time consuming, it isn't as much physical labor. The pieces aren't heavy and buffing it wouldn't be hard work. Long process sure, but not as physical nor is the same level of "craftsmanship" required. (
WHAT?!!
The rest of my response is censured!
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Post by Chuck(G) »

quote]Still, that while time consuming, it isn't as much physical labor. The pieces aren't heavy and buffing it wouldn't be hard work. Long process sure, but not as physical nor is the same level of "craftsmanship" required. [/quote]

Somewhere, somewhen, I seem to remember hearing that the guys who work/worked on the Cerveny line doing tuba buffing were the only workers provided with "lie down and take a breather cots". Don't know if it's really true, but I can believe it.

Tuba buffing? Oh, my aching back...
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Post by ThomasDodd »

Joe, Dan.

I appear to have worded it a bit incorrectly. Holding a tube next to a buffing wheel is not as strenuous as pushing out a dent, at least not the ones I'm pushing out. Making the tube round, whith the proper taper takes an artistic touch I don't have (see auto body aside) either.

I did not say it was fast. A dent that takes 1 hr to reshape, probably takes 2+ to polish.

As to the job offer Joe, given the time required, I doubt I coud do a horn in a day. Since I currently make more in a day anyway I'll have to pass :)

Chuck, I wouldn't think brass repair shops would have some one constantly buffing tuba parts. Now, 8 hrs/day 5 day/week would be rough on the back. But a few hours a week? Most backs could take that. And you can take a break, and work on something simpler when you need to.

Come on guys, I was trying to complemnet you on the artistic side of reshaping a piece of brass. I find it hard to believe you honestly find buffing more artistic or strenuous.

But then again somepeople enjoy running 20+ miles. To each his own.
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Post by Dan Schultz »

ThomasDodd wrote:Joe, Dan......

I appear to have worded it a bit incorrectly. Holding a tube next to a buffing wheel is not as strenuous as pushing out a dent, at least not the ones I'm pushing out. Making the tube round, whith the proper taper takes an artistic touch I don't have (see auto body aside) either....
....Come on guys, I was trying to complemnet you on the artistic side of reshaping a piece of brass. I find it hard to believe you honestly find buffing more artistic or strenuous.
Thomas,
Your feeble apology is accepted... only because it's obvious you know absolulely NOTHING about the brass repair business. Farting around in your garage with a body dolly and grinder is nothing compared to spending 8 to 10 hours a day in this profession. This is very tough work that requires strength, knowledge, dexterity, and stamina... just to name a few characteristics.
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Post by Chuck(G) »

ThomasDodd wrote:Chuck, I wouldn't think brass repair shops would have some one constantly buffing tuba parts. Now, 8 hrs/day 5 day/week would be rough on the back.
Hey Joe, what ever happened to that guy you called Buffer Boy? Did he just get tired of buffing the silver plate off of sousaphones and quit on you? :wink:
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Post by Leland »

And I'm just happy being able to replace a dislodged spit valve in less than ten minutes...
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Post by Chuck(G) »

Tom, I wonder if you're doing something wrong, if dent removal from a bottom bow is that much physical effort.

I don't know what tools you have, so I'm just guessing on this one.

But if you've got one of those "almost smashed flat" bottom bows with really deep dents, things will go a lot easier if you anneal the dented areas first--and you'll avoid splitting the brass as you work.

Just a thought...
________________________________________

Make no mistake about it:

I've got a tremendous amount of respect for those guys who do brass repair for a living, spending their summers working on horns that have had the cr*p beat out of them and returning them in the fall looking like new.

...only to start the cycle all over again the next year.
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Post by ThomasDodd »

Chuck(G) wrote:Tom, I wonder if you're doing something wrong, if dent removal from a bottom bow is that much physical effort.
I don't know. I'm not a pro at this. In fact it's my first attempt.
Some places smooth out "easily" in just a few minutes. Others seam to have no give at all.
I don't know what tools you have, so I'm just guessing on this one.
Not much. A long rod with a ball on the end. The rod has been bent as I work around the bow to match the curve.
But if you've got one of those "almost smashed flat" bottom bows with really deep dents, things will go a lot easier if you anneal the dented areas first--and you'll avoid splitting the brass as you work.
That sound like a good description of it. Not just almost flat though, it's dented in. The inner curve was fine for haldf the O.D. The outside of that curve is almost touching the inside, maybe 1" of space. I wonder if the denting hardned the brass there? I didn't think it would work harden that way. I thought it took multiple dent/undent cycle to harden. Can just denting further and further harden the brass?

I now have access to Oxyacetelyne torch, but not sure about annealing. I bent the steel rod holding the ball, but it's 3/4" and solid. I'm not confident about heat a thin walled tube (less than 1/8" is thin to me), and even less sure about brass. I'm using propane for soldering since it won't overheat the brass.

-Thomas "wishing I had the master's skill and experience, and knowing I never will" Dodd
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Post by Chuck(G) »

ThomasDodd wrote:I now have access to Oxyacetelyne torch, but not sure about annealing. I bent the steel rod holding the ball, but it's 3/4" and solid. I'm not confident about heat a thin walled tube (less than 1/8" is thin to me), and even less sure about brass. I'm using propane for soldering since it won't overheat the brass.
Leave the oxyacetylene torch behind--it'll do the job, but it's also hot enough that you can do real damage with it. Propane for annealing is fine--you need only heat the brass until it glows a dull red, then let it air-cool. Easily within range of a propane torch.

One thing that seems to confuse people on torches is heat vs. temperature. A small hydrogen flame has a high temperature, but you can pass your hand through it without getting burned, because it doesn't produce a lot of heat.

The trick is to use a flame that has sufficient heat but only a high enough temperature to do the work. When I'm annealing parts, I use one of those propane "turbo" tips. Produces lots of heat, but isn't of a high enough temperature to melt brass. When I'm silver-soldering, I use a small pencil tip fed with MAPP gas--just high enough temperature for the solder to flow and I can solder extremely thin brass becasue the temperature's not too high, nor does the flame produce too much heat.

The right tool for the right job.

Working very dented bottom bows can be tricky because you can distort the shape of the "U" of the bow, so that the legs of the "U" begin to slant toward each other. Some folks solder a rod or two between the legs of the U to brace things while working so that doesn't easily happen. Denting usually stretches the brass and you've got to be careful that the extra surface area doesn't wind up changing the shape of what you're working on.
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Post by ThomasDodd »

Chuck(G) wrote: Leave the oxyacetylene torch behind--it'll do the job, but it's also hot enough that you can do real damage with it. Propane for annealing is fine--you need only heat the brass until it glows a dull red, then let it air-cool. Easily within range of a propane torch.
Ok. I didn't realize propane would work. I figured MAPP would, but my torch head isn't suitable. The next tool I have access to of oxyacetylene.
The right tool for the right job.
If I could affort them, I'd buy them. Then again if I could afford the right tools, I could just pay somone else to do the job correctly :)
Working very dented bottom bows can be tricky because you can distort the shape of the "U" of the bow, so that the legs of the "U" begin to slant toward each other. Some folks solder a rod or two between the legs of the U to brace things while working so that doesn't easily happen. Denting usually stretches the brass and you've got to be careful that the extra surface area doesn't wind up changing the shape of what you're working on.
Currently it still fits back on, but I haven't done much to the worst sections yet either.
Thanks for the tip. I think I have some small rods I ca use to brace the bow.

So after annealing and removing the dent, I should harden it back?

-Thomas
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Post by Chuck(G) »

ThomasDodd wrote:So after annealing and removing the dent, I should harden it back?
How would you do that? Brass is hardened by work-hardening; it isn't like steel that can be hardened by quenching. If you quench annealed brass, it'll still be soft.

That's why it's important that you anneal only the areas that you need to work on and not the whole thing.
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Post by ThomasDodd »

Thanks Chuck.

The bow is almost round now. Looks like a dented tube instead of a C. :)

How quickly does brass workharden? I annealed the worst section 3 times, and still got a crack. I could get the tube to lift about 1/2" to 3/4" easily, then it got stiff. Is that normal, or am I still doing something very wrong?

I'm trying to be careful, and not make the crack worse, but it's next to a dip that need to come up for the brace (the flat, thick piece of brass that goes on the outside of the bow) to fit correctly. Any hints to keep the crack from getting worse?

-Thomas
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