Instrument repair

[Chuck(G)]

If you don't want solder or flux spread on other places, do what pipe organ manufacturers do on their pipes, where they are soldering metal that is the same consistency (and therefore the same melting point) as the solder: coat with whiting, or powdered calcium carbonate mixed with basic gum arabic. Coat everything in whiting, scrape off where you want to solder, use a good steady hand of flux and solder as described above, and the whiting will repel the flux and hence the solder, making a clean joint. Then after it cools you wash everything off and buff to a perfect solder joint.

Commercial solder mask is much easier to work with--just paint it on, peel it off.

http://www.wassco.com/kestcpeelmol.html

[pulseczar]

I forgot to put that I use 50/50 for gap filling like French horns, where the wrap is very tight and in the places that are too narrow for braces, 50/50 is much easier to handle than having 63/37 drip everywhere.

[Daniel C. Oberloh]

All this conversation about different solders, flux, masks, etc. Makes me think I am doing something wrong....... No, I'm pretty sure I know what I am doing. I have been known to perform some of the most extensive repair out there and I only use 70/30 and Nokorode paste flux. Silver-solder or brazing? sure, all the time. Now and then I will use a lead free or low temp silver bearing solder for piston port repairs in order to avoid plating problems that lead solder can cause when building up a piston for a valve job. Fill gaps and voids? I don't do that, it goes against my grain and I don't offer it to my clients. The job is in to be "repaired" i.e. damage corrected properly. I guess I suck at cutting corners, oh well.
If you offer bargain basement and cut-rate, thats the kind of work you get, over and over.
Advice to me when I was an apprentice was to simply learn how to make a good proper fitting joint, if it is distorted, correct it, if it means spending an additional half hour to get it right, don't piss and moan about it, (whiny voice " I'm not getting paid enough to do this kind of work") just shut up and do it. Silver plate? same process, but with a little more care. Not rocket science, just lots of practice until you have it down pat. I know, there are all sorts of aids such as masks and heat fences and I have experimented with a lot of them. I have found none that out perform mastering the control of heat and good preparation.

Brass band instrument repair skills that must be mastered are:
Soldering and brazing
Dent work
Polishing and buffing, A chimp can spray lacquer.

The above are the things you MUST fully understand if you want to repair brass. It will take years to get it down and it will take longer to develop personal standards of quality. I had those standards hammered into my thick skull by craftsmen who new there sh** and that was the toughest part of all. Just like learning to play an instrument, the more study and practice you do the better you will get.

Daniel C. Oberloh
Oberloh Woodwind and Brass Works
www.oberloh.com

[pulseczar]

Fill gaps and voids? I don't do that, it goes against my grain and I don't offer it to my clients.

I'm curious. When you say gaps, do you include tubing to tubing solder work? I personally dislike having to goop solder to bridge a gap. Whenever I do the tubing to tubing solder work, I try to make each part touch as well as make sure the brass is not stressed before soldering it down.

[Dan Schultz]

Brass band instrument repair skills that must be mastered are:
Soldering and brazing
Dent work
Polishing and buffing

Very well stated, Dan. I would add one more item to your list:

Use of a three-cornered scraper!

They could (should) teach a full semester of how to use a machinists scraper and another semester of how to use 'Machinerys Handbook'. Most everything else can be OJT!

[Chuck(G)]

The fallacy in filling gaps with solder is that there's no structural integrity in solder. Eventually, it will fatigue and break. A well-soldered joint should last pretty much forever.

Where a soldered joint gets its strength is by molecular bonding to the base metal, not in solder's affinity for itself. If joints don't fit well enough to "wick" solder into the joint by capillary action and solder must be pushed in to fill a gap, there's nothing but trouble ahead.

For an example of what's going on, take two very clean sheets of window glass and place a drop of water between them. You'll find that it's almost impossible to lift one piece right off the other. Yet, if there's a small gap, the sheets of glass are quite easy to separate.

[iiipopes]

As usual, Dan, Chuck(G), and Lee have cleared the slag off the molten metal and poured a pure ingot once again. Of course, whiting would not be used on brass as the solder and the brass are dissimilar metals; I just wondered if anyone would bite.

[Daniel C. Oberloh]

The fallacy in filling gaps with solder is that there's no structural integrity in solder. Eventually, it will fatigue and break. A well-soldered joint should last pretty much forever.

Where a soldered joint gets its strength is by molecular bonding to the base metal, not in solder's affinity for itself. If joints don't fit well enough to "wick" solder into the joint by capillary action and solder must be pushed in to fill a gap, there's nothing but trouble ahead.

For an example of what's going on, take two very clean sheets of window glass and place a drop of water between them. You'll find that it's almost impossible to lift one piece right off the other. Yet, if there's a small gap, the sheets of glass are quite easy to separate.

Thats the sort of stuff one needs to learn and apply. There are a number of Techs. who do improper repair not because they don't care but because they don't know better. The best training does come OTJ but only under the supervision of a Master Journeyman Forman, preferably one with a good deal of patience, unlike myself.


Scrapers have there place but I really don't use them that much. (except for cleaning tube ends on the lathe. It all goes back to having really good soldering technique. Its all in how you go about it i
as to how much scraping one is called to do. I am assembling a B&S Crown BBb and have yet to do one bit of scraping. I will let you know when I get out the hook.

The key to good quality solder work:

-Excellent surface prep.
-Well fitted parts,
-Good heat control

(No, I don't tin my joints. In my opinion, Its an extra step that takes more time and wastes material and delivers nothing in the quality of the final product)


Daniel C. Oberloh
Oberloh Woodwind and Brass Works
www.oberloh.com

[Daniel C. Oberloh]

I'm going to risk assuming that Dan will agree with me when I state that *any slight difference in tin-lead percentages and flux make-up can MORE THAN EASILY be overcome by a clumsy end-user.



bloke "Just hand me a spool of solder and get out of my way."

Alas, I fear this statement is true. Both for technician and player alike.


Daniel C. Oberloh

[Chuck(G)]

Boy, Joe--you're really high class! I'm stuck using this "amateur's solution":

<img src="http://www.bondo-online.com/fileshare/p ... es/294.jpg">
<img src="http://www.lacywest.com/EmeryPaper.jpg">
<img src="http://www.eurofixings.co.uk/images/rustins/gold.jpg">

[Dan Schultz]

Duct tape!

[iiipopes]

I agree with bloke. Especially if the repair was not done correctly the first time, and, from experience, where someone at an indoor concert may notice (or may not), noone will notice from either the edge of the street of the parade route, or up in the stands of the football field.

And notice he said emergency repairs, and I'm sure he means the difference between getting the show going or not. You must do what it takes to get the show going. You'll have at least a week afterwards to sort it all out before the next show.

[Daniel C. Oberloh]

OK...Call me a "hack", but I HAVE used "gold" or "brass" aerosol paint on SUPER-quick (ie. "emergency") sousaphone repairs...and I've used some of that chrome tape (or some of that super-glossy silver aerosol paint) on the same sort of repairs on badly-worn silver sousaphones.

When the finish of the repaired area looks like crap (wiped clean) and I don't have time to buff it, I'll ask the waiting band director if they want a quick spritz of gold-colored or brass-colored paint. 99% of the time the answer is "Yes."

Okay, your a ..... No, I won't say it. Still, I don't understand. If it is an emergency, no frills, "git-er-done" project, why does it matter if it is the right color and why would you give a crap? If they are going to bring it back and have it corrected the way you know it should be, why make more work to clean up? Accept for the Army and Navy bands, I don't deal with much in the way of marching horns but still, its marching band. The horns are beat up, dented and have plenty of repairs. Will anyone really notice?

Daniel C. "scratching his head in confusion" Oberloh
Oberloh Woodwind and Brass Works
www.oberloh.com

[Dan Schultz]

OK...Call me a "hack", but I HAVE used "gold" or "brass" aerosol paint on SUPER-quick (ie. "emergency") sousaphone repairs........ When the finish of the repaired area looks like crap (wiped clean) and I don't have time to buff it, I'll ask the waiting band director if they want a quick spritz of gold-colored or brass-colored paint. 99% of the time the answer is "Yes."

....... The horns are beat up, dented and have plenty of repairs. Will anyone really notice?

Daniel C. "scratching his head in confusion" Oberloh
Oberloh Woodwind and Brass Works
www.oberloh.com

I guess I need to chime in here.... There are a couple of you guys who tend to specialize in 'restoration' work that needs to be perfect. However, most repairmen are challenged with the task of just "keeping 'em playing" until the next football field 'crash'. Are the marching band directors going to spend big bucks for 'restorations' when the horn only needs to be presentable at 100'? I don't think so. Do I always do the repair I think REALLY needs to be done? Nope! Do I "keep 'em playing"? Yep! Is everybody happy? Yep! I make a little money and the tubas/sousas survive until the next big fundraiser.

Oh.... I CAN do the job right when the right money is involved ... Having customers who are willing to pay for the 'perfect' job doesn't happen very much in the real repair World.

[iiipopes]

Listening to these war stories, I am reminded that when I have to I can crawl under the floor space, dissassemble and sweat in a new plumbing fitting when an outdoor faucet starts leaking, and manage to avoid burning down the house doing it. With that experience, which I hopefully won't have to do again for a couple of decades depending on how bad the winters get, taught me appreciation for the guys who can fix horns properly. Believe me, there is no do it yourself here if a solder joint needs redoing, even in spite of the fact that if I wanted to you couldn't tell from looking at my tuba.

So guys, as far as I'm concerned, you all have ample job security.

[Chuck(G)]

I just wanted to you all to know that I'm a convert...

I used some 50/50 solder this past weekend.

--to install a new water heater.

[Dan Schultz]

I just wanted to you all to know that I'm a convert...

I used some 50/50 solder this past weekend.

--to install a new water heater.

Glad you got that job all finished up. We're in Evanston, Wyoming tonight... headed for Salt Lake City in the morning... then it's California or bust. Hope to see you sometime next week.

[windshieldbug]

then it's California or bust

Why does it have to be California OR bust?...

[TubaRay]

then it's California or bust

Why does it have to be California OR bust?...

I believe you're right. There must be plenty of busts in California.