Late 1960s tuning-in-the-playing-slide Conn bass trombone save

[bloke]

I'm already into this project. A couple of people have seen a little bit about it on the bass trombone page on Facebook, but I haven't posted much about it there. Tomorrow, I'll either flesh out this post or reply to this post if someone else decides to comment before tomorrow. This thing was quite distressed and was bought new by the parochial school (1969) that still owns it. I know who sold it to the school, and I know why (store owner was brother of the band director, who was a bass trombonist). It was made in Elkhart, Indiana which was the only year this model was made there, because the year after this model was released, the factory was moved to Texas and subsequent instruments were engraved USA rather than Elkhart indiana.

I did the best I possibly could of saving the slide-tuning playing slide. The outside slide tubes are now very straight, there are no slow spots or drags, but there are very "ticks" where epic dents formerly we're located. I really don't want to jack up those tubes with one of those slide expander things. I had to replace the top inside tube along with the hopelessly stuck venturi (mouthpipe). I happen to have those in stock. New production was very close to the same exact size...perhaps a thousandth of an inch larger. I spent several hours today on the solid non-tuning back bow of the bell section, which was beat to hell. I think I've got it shaped about as close as I can manage to get it to its original shape. It was all hand work. There are really no quickie machines that can help repair a part like that.

I judge this instrument as being too fragile to put back into service at that school. They own a much newer two rotor inline bass ("112H"...??) that only needed a couple hundred dollars of repair work (done), and I think they should only use that one.

This is officially the last instrument of the hundreds which were in the barn making up the up the huge pile of so-called "summer repairs". They were in no hurry to get it back, and I told them that I would get the other one taken care of and back in their hands quickly. I kept that promise, and they should have this one pretty soon, now that I've made a great deal of progress on the bell sections fully tapered hand-repaired back bow. Again, I hope that maybe only the current band director uses it or something like that, as he happens to also be a bass trombonist as was the band director who bought the thing well over a half century ago. The single rotor 60H and the dependent two rotor 62H were different from the 71/72/73H bass trombones of that era, in that the 6xH instruments featured a huge bell throat and were made of gold brass - including that back bow part that I've mentioned a couple of times.

[bloke]

Here (link) are some pictures of the model. I'm linking a website of one that was formerly for sale and ended up being sold. You will see the gold brass metal throughout (other than the F attachment yellow brass tubing), you will also see tuning in the playing slide, and the lack of a tuning slide in the bell section. This was sort of a reintroduction of an instrument from two or three decades earlier called the 70H - with some minor differences.


https://www.musicalinstrumentcity.com/p ... al-p23858/

[bloke]

after a whole bunch of hard burnishing...
light scratchy marks, even with grease and a pad (LOTS of pressure) and an inordinate amount of hammering required as well

It's not perfect (particularly when one sights down it towards a light source), but I'm not sure how much better I can get it.
Yes, I'll polish it purdy, but no filing nor sanding.

bloke "Hey...I didn't break it."

[bloke]

The outside tubes - soldered to the playing slide bow - are not stabilized.
Notice that the one (link: sold) has a brass aftermarket brace which functions to stabilize.
I'm going to go back (finding a narrow diameter NICKEL cross-tube which looks Conn-like) and do the same thing.
It will require me to remove a little adjustment screw-accepting appliance and - instead - drilling a hole in the new cross brace (just as with the one on the linked website).
ie. I'm going to do the same as they did, except
- nickel
- smaller gauge
(ie. lighter weight and better-lookin')

[bloke]

I decided that - without adding a brace to stabilize the outside slide assembly, this thing wouldn't be long for this world (particularly not put back into a school environment). Even gently polishing the insides of the outside tubes was causing them to twist within the tuning appliance, so...

I removed the little dinky "Connstellation trumpet 1st slide-lookin' appliance, installed a brace (nickel/narrow/Conn-made - harvested from a Director trombone main slide), drilled a hole to accomodate the tuning screw, cut it down, and installed it.

Yes, that brace (as small as I could manage) adds weight...big whoop.

You'll also see where I UN-trashed the playing slide bow and UN-trashed its water key as well.

Also (again), I could not salvage the upper-inside slide tube, so you'll see where I heated the inside slide hardware, extracted the bad one, and installed a new one (along with a new venturi. I also ran a Jarno reamer into the venturi to assure the solid fit of a bass trombone shank mouthpiece.

These tuning-in-the-slide playing slides (particularly when one needs a part that the factory didn't put on there - as well as beat to hell) are sorta complicated...

...yeah...I'll shine up and shoot the areas that I uglied up, but not the entire playing slide assembly.




This slide lock ring is out of my (USA) Blessing B-88 parts drawer:


goofy-lookin', yes...??

[bloke]

I went back and added about .005" width to that new brace, and the whole thing measures really consistently all the way up and down. When installing braces, they tend to shrink when they're cooling (duh).

I also went back over the worst dent in one of the outside tubes, grimaced a little bit, and went ahead and used the expander tool on that dent. It was a good decision.

[bloke]

Jeff Reynolds is a friendly-acquaintance, and told me that the added brace (for good stability) would have an affect on the resonance.

I don't necessarily doubt him, but "a young scholar twisting it and destroying" it would surely have an even more detrimental effect.

It will stay.

[bloke]

I polished and lacquered (only) the areas of the playing slide which were subjected to soldering.

again: This entire instrument was trashed. I had to remove both the F-attachment dogleg/slide tube AND the rotor-with-lever in order to remove severe dents from the horizontal portion of the F-attachment circuit.

The 1969 factory epoxy lacquer was/is very resistant to stripping. I've given up on a small portion of it, which will be buffed off.

The bell (itself) is roughed out, but all the huge dents are still small dents.





I'm not thrilled that I had to pull this apart this far...

[bloke]

I finally managed to get all the lacquer off the bell.
I had to surrender and buff some of it off, but - prior to surrendering - I did get the stubborn spots down to smaller spots.
I did get all the lacquer CHEMICALLY stripped off the engraving.

I'm fantasizing about getting the bell smoothed out, getting this bell section stuck back together, and getting this thing (the parts that are stripped) polished and lacquered today. again: fantasizing

Then again, it's just a trombone...not some Yamaha YBB-321 nightmare, or anything close.

[2nd tenor]

I’m maybe a little slow and a little confused, sorry but I am trying to keep up.

I think you’re doing work on a Conn 60H. Single rotor Bass Trombone and tuning in the main slide.

I think that this is as they were built … seems a flawed design to me, but I’m not clever enough to work for Conn.
https://swisstbone.com/conn-60h-bass-tr ... age_1%5D/4

As per your link above what you’ve done has been done by others: https://www.musicalinstrumentcity.com/p ... al-p23858/

There’s a fancier (better?) way to do similar but you’re working to a limited budget. https://brassark.com/sale_horns/conn-60 ... lds-slide/

I think it daft to put such fragile and valuable instruments in the hands of youngsters. Maybe the school should sell it and buy something more durable.

[bloke]

The assistant band director is a bass trombone player, and the instrument has belonged to the school since it was new, so I don't think it's going to be traded away. I've seen what you showed me in your pictures before, but it involves even more additional weight and doesn't do anything different. I believe the earlier model 70H - which tuned in the playing slide - may have actually had a tuning wheel built into that cross brace and surely weighed even more. Doing it the way that I did it allowed the threaded stop rod to stay where it originally was. At least I fished through enough parts to find a brace assembly that was nickel and also Elkhart/Conn-made.

The tricky thing about an intermediate brace is that - when any brace assembly contracts - it cools, so I had to install it and then go back, heat it again, and tease it back out to the correct spacing - so that the slide assembly wouldn't be hourglass-shaped.

I may have already posted this observation - and I apologize if I have, but when I got it to the point to where it could be played, I was surprised at how barky it sounded - rather than mellow. I expected the opposite with the huge bell throat.

[bloke]

I got this bell section ready to color buff today before I had to go play somewhere. I'm leaving a lot of the factory lacquer on the F attachment circuit, as well as the rotor casing, because - again - this lacquer is so very difficult to strip, and those areas are so very tedious. The small stripped/re-polished parts of the areas immediately described above were so stubborn that I ended up sanding off the burned lacquer and then hand polishing out the sandpaper scratches. I never do that, but I had to this time. I hope this thing finds Its way into the case and ends up being latched by me for the last time tomorrow. I have other stuff to do - the next being another one of those wonderful all smashed up Yamaha BB-321 tubas.

The trumpet player I worked with this afternoon never ceases to amaze me as to how much talent they possess. A couple of days ago they had two tooth extractions. They were a couple of side by side molars. Not only did that person play beautifully today, but it was 98 in the shade at 4:00, 95° by the time we started at 5:30, and he held his pitch at reference 440 and - as always - played like an angel. This person also has a chronic life-threatening health issue which I'm not going to go into, but no one would ever know it from their playing. Thankfully, I was using the old B&S F tuba which - as others know - requires being pushed in most of the way at normal operating temperature, so I was able to pull and match his 440 reference pitch. Even though it was hot, we had a little roof over us, the roof was actually in the shade already, and they had set a 42 inch fan facing towards us about 20 ft away, so it really wasn't that bad, with the final positive factor being that the humidity was only 65%, today.
I played this event last year and it took me until this year to figure out that (as we were playing at a highfalutin assisted living/nursing home place) a lot of those people donate a lot of money to the arts, and it was an annual sort of "look at all these people that you've been supporting, thank you so much, and - by the way - here's some liquor, some nice food, and a party for you" thing.

[bloke]

I'm sort of proud of a case adaptation I just made. A generous person (right here on this site) donated a nice Italian made hard case to this school to house this instrument. The playing slide fits into the slot as long as the tuning mechanism is completely retracted, but - at least, for me - it needs to be pulled out about 3/4 of an inch for A=440 tuning, and it just won't fit unless it's retracted. I managed to pull a couple of pieces out of the interior, glue everything down, and adapted it to accommodate the longer playing slide without having to retract it each time, and I'm also sort of proud of the fact that it doesn't look like I tore a bunch of stuff out of the case; it actually still looks nice inside.