The Great Kurath Re-Tubing

[the elephant]

Getting there!

I have had a lot of issues with these beater French horn parts, to be sure. Now the low price is finally starting to be worth the effort. I might upgrade to Miraphone tenor tuba rotor paddles, but the junk I have is nice enough now that I am hoping this will be a permanent solution. I have wasted far too much time on getting these levers to work well and look decent. I am ready to move on to installing the stupid things!

[bloke]

Even though I have played a 6-valve F for forty years - and it’s the only F tuba I have ever owned, it still messes with my mind to play stuff like that nearly-repetitive low passage in the “Prologue” of that Empire Brass “West Side Story” suite.
I’m pretty sure that Pilafian always played it on a C - originally with one of those challenging-intonation “Bell“ models. (I always bring a C or - now - perhaps/probably B-flat instrument, when that “Prologue” is programmed on some quintet gig.)

[the elephant]

I worked out that accursed part years ago on a 5-valved F. It sucks mightily, but I always end up having more trouble with the arrangement of "America" from that suite. And yes, he recorded that on his Bell model CC. I think ML might own that tuba and that I might have looked it over.

At this point in my life, I'm not really sure whether I would bother with relearning that low lick in the "Prologue" with the extra valve.

Stranger things have happened, though. Why just the other day I farted a big cloud of daisies.

True story.

[bloke]

I (geez…sorry!!) keep changing the subject away from the subject at hand – “upgrades and enhancements to a Swiss-made F tuba” - but to the just-previous subtopic of “passages which are awkward when playing them on F tubas - and (perhaps) challenging to play in-tune-or-delicately on F tubas - as well as many large bore C tubas”, I continue to kick myself for not previously having rounded up for myself a plain old easily-played-in-tune medium large bore B-flat tuba. Hell…They’re probably not as good as what I ended up with, but a King or even an Olds I-99-4 (had I owned and used one - when appropriate - at many various opportunities over the last half-century of check-chasin’) would have auto-solved so many issues.
After sweating bullets so many times playing those flat-key chords in the Dvorak, I just felt so damn dumb playing them last week - and having them be so absurdly easy on (basically) a plain-ol’ “school“ tuba.

bloke “yeah… It has a fifth valve and really well-aligned slides, but I didn’t move any slides, and I didn’t mash the fifth button.“

[the elephant]

Frozen, wet, pissed off, but at the same time happy that *most* of this tedious work is not out of the way, I sat outside in the wet, at 42º F, for five hours. I had a minor tragedy, too: the hose on my torch snapped off when the tank fell over. Idiot move. I was very fast and turned off the tank within a few seconds. I also removed the torch altogether and tested the three joints on the tanks with soapy water for leaks. It is fine. My regulator is toast. I need a new hose and gauge, too. The handle is fine though. I have a Uniweld torch (better, but with too large of a tip) to use until I can replace the parts. (BTW — Uniweld torches are MUCH better than Goss torches, despite being half the price. Just sayin'…)

I made all eight detachable brace assemblies today. This involved marking, masking off, hand-cutting, then deburring eight flanges from some junk tube of the correct ID, then silver soldering the eight new flanges to the threaded sockets I am using. After all that had soaked in some pickle to remove the "glass" from the silver soldering paste flux, I dragged the buffer outside and did all the PITA detail work to prep little bitty crap for assembly. (I the buffing.)

I also fixed/adjusted/corrected/whatever the hinge rod for the levers, using the new "Bach stop nut" knurled thumb nuts from McMaster-Carr.

Et voila…

All masked for DremelFest '22. I wanted the flanges on both sides to be the same size, and the leftover ones I made for the Holton were too large, so I decided to make new ones.


I have to cut these using my GI Mk1 Eyecrometer and a Dremel tool, so the edges come out UGLY and have to be deburred and "massaged" so they look decent.


There! The flanges have been cleaned up enough to be silver soldered to the threaded bosses. Before I did that I spent about 30 minutes with a sax tone hole file cleaning these up to look less homemade. They turned out pretty good, in the end.


Here is the complete set of parts for all eight braces. The little brass guys in the lower right are keepers for the ends of the brace rod.


Here are the uber-sexy hinge rod nuts on the lever set. It is almost done. I still have to shape and thread the lever arm "stumps" that will have Minibal joints on them.

[Tubajug]

Nice! So are you replacing all the removable hardware on this horn as you go?

[the elephant]

Yeah. I was using three different types of detachable braces, and of those one proved to be the best, so I am switching everything over to that type. As per my usual with all-brass horns (which I dislike, personally) I am using this as an opportunity to swap-in nickel silver parts. I prefer nickel silver for all bearing surfaces and stuff that is load-bearing, so valve bearings (if possible) slide tubes, and braces. I am sort of making this into something that looks like a nicely trimmed 186.

As a raw brass horn without a bit of silver to help bring out depth and color, it looked like a big, brown blob from a distance. So did my Holton, once I had all the silver plate off of it. I love brown, unlacquered horns, but you must have a LOT of nickel silver trim that is highly polished to offset the brown. By itself, the brown is pretty ugly. However, when it is set off by lots of adjoining silver stuff suddenly the brown looks quite beautiful to my eye.

My 186 is a lovely instrument, so I am modifying my two other work horns to have approximately the same overall look.

Anyway, as to the braces: What got me on this mad caper for removable valves was my old prototype Kalison DS. Being able to take the valves off for cleaning or polishing made everything so much easier and faster for me. I loved it!

I had never thought to do this to one of my own horns, though.

Then someone here, either Tabor or Brett or one of the guys posted a photo of a 5th valve section he had made detachable using parts for the original version of the "new" 2341 and it hit me like a bolt from the blue. I got all the part numbers and started ordering stuff and then this Kurath had removable valves. Of course, the King braces were not long enough for some things and were way too long for others, so I added in Edwards trombone braces and Yamaha sousaphone braces and everything worked out really well.

Over time I decided that I disliked the Yamaha braces. I had to modify them twice before I really felt they were what I needed.

The King braces, though, turned into a problem for me, at least in my head. There is a section that is *very* weak and is actually thinner than a trumpet MTS brace rod. I did not want my expensive Kurath to have the vale section accidentally pulled off because these braces failed.

After having built an Edwards brace that had been cut to the absolute minimum functional length (on the Holton) I realized that I could indeed fit them into the spaces occupied by the King stuff. The little Yamaha brace could not be replaced, however.

Since I decided to reroute the 4th slide I am no longer hampered by the Yamaha brace. I can account for the space needed for a super short trombone brace (a la my Holton) as I lay things out.

So the weak King braces are out. The Yamaha brace is out. Now I have a set of these nice, twist-barrel braces. And the added benefit is that I will no longer need tools to take down the horn. It is all finger assembly! I love that!

Note that the leadpipe has one of the King hex-headed screws at the mouthpiece, but that will be replaced sometime soon.

Thanks for asking. I'm sorry that my explanation was so long.

[York-aholic]

DremelFest '22.

[the elephant]

DremelFest '22.

Ah, someone feels my pain…

[the elephant]

Torch update…
[To be filed under "Who Gives AF?"]

So I had a minor disaster the other day that has totally stopped me from working. My B tank fell over. Okay, dipstick here knocked it over. You are not supposed to use an Acetylene tank that has fallen over, nor are you supposed to ever use it when it is on its side. This is because the acetone inside can start spraying out of the torch tip and cause all sorts of nasty fun. I think for the amount of time this one had been on its side it was safe to use again in about five minutes. Having many years ago been in a building where one of these tanks exploded I always ere on the side of "Don't incinerate me, bro." So I waited for about an hour to use it again. I know, I know… it normallyi is strapped to the workbench leg, but I failed to do so on that day, for whatever idiotic reason.

These tanks, when on solid concrete, fall over with a muted "clump" sound that frankly could have been any number of things… but it was the audible hiss of gas venting into my carport that caused me to click into crisis mode.

The hose had snapped off at the regulator! Not cool! Not cool! FML!!!

I turned off the tank using my "hunk of 2x4" as instructed by the idiot Counter Troll at the local AirGas outlet. ("Just whack that lever with a hunk of 2x4 and it'll be good.") I have complained to them about six times this past year that the valves leak on the B tanks I keep getting from them. Jerks.

Once turned off using the high-tech 2x4 whacking method I removed the broken regulator, the broken gauge, and the snapped off hose/handle. I then did the soapy water test to the valve stem, the seat in the tank, and the nozzle.

No bubbles anywhere.

Tank stored.

Elephant pissed.

Today I dug out my trusty Uniweld gear and the Goss "trash". I was told repeatedly by reps from BOTH Goss and Uniweld that the tips, hoses, regulators, etc. are NOT compatible. I only dropped the extra cost for the Goss ($300+ versus the $150 Uniweld kit) because NO ONE at Uniweld wanted to help me get the tips I needed. No help. No interest. I think they work on commission and don't G.A.S. about little shops with a single air-acetylene rig. All of them over the years tried to hard-sell me large oxy-acetylene rigs or welders.

F.U. Uniweld. Better, cheaper product, but craptacular customer service. I think all these guys must be related to Napoleon's Uncle Rico. Sheesh…



Of course, my twice-as-expensive Goss torch sort of sucks. I hate that regulator and I hate the valve on the handle.

Hate.

As in the opposite of love.

However, the Goss tips are easy to find, and that is why I have been using that overpriced, crappy torch.

Today I finally found the specific tip needed for my Uniweld handle. After I bought it I noted that the description says that it is compatible with my Goss handle. This is from a place that just sells torch tips. (I know, sort of a niche market, like a 24-hour wicker furniture store…) So they do not have a horse in this race.

WTF?

So does this mean that the Goss tips will work with the Uniweld handle? The fittings all match, the hoses are the same, made by the same company, and are rated the same. However, all the inside apertures and filters are different. Could it be that one handle can use both brands while the other can only use its own stuff? I have seen this in many items, where one has a specific fit and the other is a universal fit that fits that same item.

I hate having to take time out to research this sort of crap.

So, I spent the money on the Uniweld S22 Soft Flame tip, and I have my old Uniweld torch cleaned up and reassembled with the larger tip that I dislike for brass instrument work. I plan on trialing all the Goss tips on the Uniweld handle later tomorrow if I feel better. (I have the flu — No, not COVID; I was tested this morning.) If these dang components have always been compatible I will call up both companies and teat them new sphincters on the phone. I hate it when sales reps lie to me or are too lazy to check on specs.

Anyway, I have a torch again, dammit.

Lucy Van Pelt, Uniweld Sales Representative

[bloke]

btw...
My small/electric/wall-inserted/forced-air heater (in my well-insulated shop, a small heater which is quite adequate)...

Well (duh), it BLOWS AIR. I can't friggin' run the torch (solder, etc.) anywhere NEAR that blown air.
...I don't know how the hell you manage to solder in the wind.

The torch (unless doing plumbing crap, etc.) is the "paint brush" of soldering. The WIND completely goofs up the "brush".

[the elephant]

It is my cross to bear, heh, heh. It causes me to waste a lot of gas, use way too much heat, and makes a horrible mess. Post-soldering clean-up is half of what I do on these projects, which is why I am so friggin' slow. If I worked in a proper shop I could slam through most of this stuff very quickly and neatly. But in a previous life, I must have seriously pissed off the soldering gods…
______________________

And now, in other news…

I will be rerouting the 4th slide to work like that on the MW 45-SLP, which will involve me cutting off one of the 4th knuckles and turning it 180º to point upwards. I have looked at several routings that are possible, and the one I want to use will leave me with a very short upper slide. The point is to get most of the pull in the upper slide, as I never use the lower for anything.

Also, I will NOT be reusing ANY of the current 4th slide parts, and hope to chop off the valve knuckle in a way that allows me to put stuff back if I don't like the changes. So that is the first thing on the list: cut off the knuckle and reinstall it so that it can be turned either way. From that point all else becomes possible.

That is all.

Carry on.

[York-aholic]

which will involve me cutting off one of the 4th knuckles and turning it 180º to point upwards.

I will be looking for pictures.

[bloke]

This question isn’t worth its own thread, so I will continue to abuse Wade’s thread:

Am I the only person, or are there others who occasionally butt up ends of bent cylindrical tubing to where they meet perfectly, silver braze them together, and then file sand, and polish the silver braised joint in the tubing (in order to create compound bends - avoiding messy lead solder connections) ?

[the elephant]

I would love to do that, and perhaps one day I will give it a try. I can do that on large cracks and holes in branches where I can see inside, in case some of it globs up internally. (So far none has; it always lies very flat for me.)

I have so far been afraid of my jig (the none-too-swift Ferree's three-armed bandit) shifting while I am heating. I was excellent with brazing parts in this manner in the late 1990s, but since I started back doing repair work in 2013 I have successfully avoided having to do much work with hard solder. Firstly, I did not know I could use my B tank air-acetylene torch for that work. I was trained to use oxy-acetylene for silver soldering. I am already nervous enough with a B tank in my carport in the weather, so a pair of A tanks of O2 and acetylene would probably freak me out. The B tank is specifically not allowed under my homeowner policy, so that is a stupid-bad risk I am already taking.

Since I have been successfully silver soldering for the past three years now with the smaller torch that is no longer an obstacle. So that means I am not doing this because I am not in the habit of thinking this way.

I will give it a try soon. I need more than a few oddball tubing runners that I could make from existing junk parts. usually I ferrule them, but that is a lot of needless work if I could just braze them together without having to cut and dress a ferrule, too.

I'm getting off the pot. I promise.

[bloke]

Once you get indoors, you’ll find that it’s easy. The ends do need to really touch nicely.
The challenge to fixing nasty spider cracks is that usually their random edges are dirty and tarnished, and burning off the dirt and tarnish risks burning the metal up within the spider cracks. With newly trimmed and filed ends of tubes, they are hungry for silver solder to run between them.

Cleaning the burr off the inside (and even beveling the inside, so that any silver solder sort of ends up in the bevel - and not sticking into the bore) - but leaving a little bit of one on the outside - makes it a little bit easier.

[the elephant]

Yeah, I remember how to do it. I just have not applied this knowledge in some two decades now.

RRRRRRRRRUST! It's what muh mad skillz be covered in.

[the elephant]

I will be looking for pictures.

And I hope to provide some.

[the elephant]

Okay, so I ordered one of these from Grainger and get to pick it up at the local store on Wednesday.

I'm doing my Happy Dance…

[bloke]

Don't forget to leave them a tip.

Okay, so I ordered one of these from Grainger and get to pick it up at the local store on Wednesday.

I'm doing my Happy Dance…