Amateur Frankentuba-ists. Use glue not solder???!!!

[2ba4t]

This also appears at 'Alternative to soldering?? Cold bonding???'

I have been busy moving continent etc. But as promised I tried 'Just for Copper' (also try'ComStarCopper' both at Amazon). It can be excellent - especially on lacquered areas - if:
1. you prepare both surfaces with a 60 emery cloth and then white spirit - just to ensure they are clean.
2. you rotate the joint as you feed it together.
3. there is not too much play between the outer and inner pipes.
4. you use suitably thick shim if there is a gap. You need to emery cloth and clean all contacting faces. But you can glue the shim padding in the receiving pipe first by using e.g. a suitably sized piece of conical wood, let it dry and then proceed with the actual joining. Fiddly but possible.
3. you line them up carefully first - 'cos this stuff dries very quickly.
4. unseal it with gentle heat and then emery and clean again.
5. you have a good bank manager. But actually a very thin thread works great.
6 you are wary using it on large bore joints. I think it may not have the same mechanical strength as on narrow pipes - leverage, thickness of material, etc.

Non-joints - It is no good, I found, for simply gluing small surface areas together e.g. the arched support for the valve below is soldered on. Its narrow feet resting on the tubing below would not 'stick'. I think you need a large surface area.

Photo0008resize.jpg

The valve is screwed to that arch.

But, it is brilliant for complex multi-jointed jobs in close proximity. None of the wiring up and fiddling, or trying to solder ten adjacent joints which keep popping apart as you apply the torch to another joint. Even those flexible-hoses with tiny torch nozzles require some very nifty soldering. This dependent fifth valve pictured above, which I put into an alternative 4th valve slide I made, works great and was a simple matter of glueing it together. It seems as solid as soldered work and is non-leak even with that ancient valve.

Photo0007resize.jpg

Should look OK when polished and lacquered.

Hopes this all help someone somewhere.

[UDELBR]

Don't know what's in 'Just for Copper', but I see enough horns super-glued together by well-meaning Dads. Problem is, when you heat most types of super-glue, hydrogen cyanide comes free in sufficient quantities to endanger whoever's nearby.

Soldering's not that hard. It's all about heat control.

[Donn]

Don't know what's in 'Just for Copper'

· Hazard-determining components of labelling:
methyl acrylate
Poly(oxy-1,2-ethanediyl), .alpha.-(2-methyl-1-oxo-2-propenyl)-.omega.-[(2-methyl-1-oxo-2-propenyl)oxy]- mequinol

Soldering's not that hard. It's all about heat control.

So if you can eliminate heat control as an issue, evidently it would be easier.

[UDELBR]

So if you can eliminate heat control as an issue, evidently it would be easier.

Like anything, practice helps.

[The Big Ben]

So if you can eliminate heat control as an issue, evidently it would be easier.

Like anything, practice helps.

Proper equipment = proper heat control. "Band Dads" don't own the type of torch which works well to solder musical instruments.

[UDELBR]

Proper equipment = proper heat control.

Nope. It's proper technique. Not hard. Requires practice though.

"Band Dads" don't own the type of torch which works well to solder musical instruments.

That's what repair techs are for. Band Dads however do fearlessly dare to apply super glue, which potentially endangers said techs when they unwittingly heat glued joints.

[roweenie]

Thanks for the tip, but I'll stay with solder and flux. Many before me, with far more experience and knowledge, see fit to do it that way, and that's good enough for me.

Also, it has to be easier to reverse or revise your work using solder (unless, you're like Mozart, where the first draft is also the final draft). Oftentimes I temporarily solder things together in the knowledge that it will be revised later in the job.

Seriously, the technique is not that difficult (proof of that is, even I can do it).....some diligent practice and observation will yield satisfactory results.

One thing I ask you to do - should you ever sell the horn with that work on it, PLEASE advise the new owner of how you constructed it. The next person that works on it NEEDS to be made aware of the media you used to assemble it.

[toobagrowl]

On my earlier solder repairs, my technique wasn't as good and sometimes the joints or parts to be soldered weren't always "sealed" the way they should. There would sometimes be small leaks at joints because the solder didn't 'flow' around and seal the joint completely. Besides my technique not being as good, I didn't use enough flux and I used lead-free solder. I dabbed a little epoxy on some of those joints to completely seal them.

My soldering skills have gotten better over the years, and I know how to use the right amount of flame and flux for joints or braces that need to be well-soldered. And that's with lead-free solder, which is supposedly harder to use

But there are some things that I have no problem using epoxy on. Like a ripped/torn valve knuckle. I've used epoxy on one of my old tubas valve knuckle. The tubing coming out of it was ripped/torn, and I had to make do with tubing I had laying around. The tubing I had was much larger bore than the knuckle tubing -- too much 'gap' to solder the parts together. So I used a lot of epoxy to bond the parts together, and soldered the lower tubing section. That part has held together for about 9 years now; no cracking or separating yet. I did recently solder (silver-bearing lead-free, my favorite ) a couple more home-made braces to the lower section of that valve tubing, and added more epoxy to the knuckle section to strengthen even more

[roweenie]

I'm no chemist (I don't even play one on TV), and I'm not trying to split hairs, but isn't "super glue" somewhat different than "epoxy"?

Does epoxy, when heated, give off life-threatening gases? I honestly don't know.

[toobagrowl]

^ I dunno. Just thought my experience fit this thread. I'm thinking epoxy is probably similar enough to superglue? I have heated and burnt epoxy before, and it stinks. Smells like burnt plastic. If you take a flame to epoxy, it will burn, turn black and get hard as glass after it cools. Very hard and messy to clean off a horn once it has been 'burned' on

[roweenie]

I was curious to know, because I'm truly trying to be open-minded and running all the changes to determine a time where I'd use any type of glue, rather than solder and flux (I haven't yet, FWIW.... )

[The Big Ben]

Proper equipment = proper heat control.

Nope. It's proper technique. Not hard. Requires practice though.

Hard to soft solder with a torch that is designed to be a "general workshop torch" running on propane and used for "heating stuff up".
Need a proper torch with a proper tip if a brass solder joint is being attempted. Then, proper technique with the proper equipment and materials will get the job done.

[Donn]

Super glue = cyano-acrylate. That first term "cyano" refers to the cyanide component mentioned above.

Neither epoxies nor this "Just for Copper" stuff have any cyanide in them. I doubt smoking them would be good for you (but then I gather neither is solder.) I think there are a variety of expoxies, some of which are currently used for instrument lacquer. Since that stuff is expected to have an acceptable lifespan, and is naturally found on tubas, it might be worth a look as a repair cement, if it's conveniently available.

Not to put too fine a point on it, but this is clearly not about how to revolutionize the instrument repair business, but how someone who isn't in that business, might work on a tuba without first botching up a bunch of other tubas while acquiring the skills needed to make good solder joints.

[timothy42b]

Glue is used on many instruments that need to be disassembled. Violins and pianos come to mind, (hide glue), of course woodwind pads, etc.

I don't know how the strength of the joint compares but hopefully the mechanics of the structure do most of the support. A ferrule on tubing might not support more than the weight of the tube.?. An exception might be a saddle joint for a linkage, where there's a good deal of force applied during playing.

Shear strength of JBWeld is about equal to solder, but nowhere near as removable and it's guaranteed to irritate your regular tech.

[Rick Denney]

When I received my Sanders (Cerveny) tuba back in the deeps of time, I thought the second valve branch had something funny going on. Sure enough, there was a gap in the solder where one of the tuning slide tubes soldered into the ferrule connecting it to the valve knuckle. It puffed air when I pushed and pulled the slide.

Sure, I could have taken it in for repair and then had an argument with That Place In Detroit Whence It Came about how to pay for it. Instead, after blasting it with TF solvent (RIP), I mixed up a bit of clear five-minute epoxy, dabbed some on the offending opening, and pulled the tuning slide slowly to draw it in into the gap.

Two things are almost certainly true, 36 years later, assuming that instrument is still with us: 1.) no torch has ever been applied to that spot, and 2.) it still isn’t leaking.

And I was enjoying my new tuba again in ten minutes.

Rick “epoxy is as sensible as solder, but in some ways just as demanding” Denney

[timothy42b]

My mini pBone cracked the weird two piece tenon at the bell slide connection.

I'm not all that skilled at soldering so I used JBWeld. Just saying.

Oh, and it's no longer a two piece.

[toobagrowl]

Yeah, imo, epoxy is the next best thing to solder on a brass instrument to fix/bond parts. The good thing about epoxy besides it's strength is that you can file/sand/polish and paint - if desired - after it cures.
And like Donn said earlier, there are brass instruments that have epoxy-based lacquer on them. Those epoxy-based lacquers are "baked on"(I think), and are arguably the best, toughest lacquer available and can last decades with care. Yamaha and some others use this lacquer

As for superglue, I have used it on a couple of my cases/bags. If my face is close to it while still wet, it makes my eyes water. There are vapors coming from it. But the weird thing I've noticed with superglue is that it "fogs up" the section it is applied with a white film that you can partially wipe away.

[2ba4t]

I have actually soldered plenty of awkward sections together, adding valves and tackling nasty soldering near to valve blocks and at the back of compensators etc. Using damp rags and heat barriers, yards of wire, cool solder after hot solder etc seems to have worked but it was hard work. It generally has held, leakfree but obviously a real pro would probably not find it pretty. [Although a good polishing hides a lot!]

I found this - on Just for Copper - from a plumber:

The first thing to understand is that this is not a glue. There is an anaerobic chemical reaction between the two metals. This creates a very strong bond that is more consistent than Soldering joints in many cases. In addition you can get up to 200 uses out of a single bottle for about 1/3 the cost of silver solder. In addition you can join pipes together in tight places or in historic buildings, hospitals, schools and court houses and there is no need for a fire permit. Just For Copper if use properly is very reliable and efficient. Again, This is not a glue or epoxy. It is a solder-less bonding agent. and also
I've seen this glue before and I've seen two grown, big men with pliers trying to pull this pipe apart after the glue has set up but I'm willing to bet that you cant find a professional plumber out there who will use this stuff.

I do not think that a pro repairer should touch it unless he informs his client; this is because it is a departure from the industry convention. Using superglue and other non-bonding agents must be questionable in that they do not make a 'joint' at the molecular level. But if the result blows, saves costs and one is honest - why not?

[basslizard]

I need to take pictures, but lacking proper equipment and skills, first I put painter's tape around the third knuckle of my euphonium, and then got brave enough to hot glue. The repair tech suggested the hot glue or epoxy, but said he didn't think he could solder the knuckle without completely disassembling the horn.

I now have a few disposable brass horns to experiment on, so now I'm leaning towards getting a torch and learning. Might take a plumbing course at a tech school.

Added a picture of the knuckle pre-repair. It's not as bad as it looks - it fits flush if you push it together, and stays that way. My hot glue is easily removable. It was hard as heck to get it in that tiny space on the underside of that valve.