AdminConn made as their original 6D model a modified Schmidt model horn with a piston change valve. In 1935 the 6D was updated into the familiar model with 4 rotary valves, but the Schmidt model double horn was produced for several more years under the Pan American name, which was a sub-brand of Conn. Most likely, I’d guess, to use up the existing stock of valve clusters.
I had a King Schmidt model horn for a few years, but, honestly, it did not play all that well and there was not a project there for me to improve it. But this Pan American came up on eBay and kind of spoke to me as an interesting project. It is much closer to the classic Schmidt design (with a modified F slide setup) and has an improved thumb valve setup. But it had many problems to address.
First steps
I was working on it by early 2024 and I’ve done a lot of work off and on. My first steps involved fixing the bell which was a big problem. It was crushed to less than 50% open in the area of the left hand. It took a lot of dent work and adding a hand guard (from a parts 8D) that covered a patch. But also I had to bend the bell tighter, filling a large section with Cerrobend, as all the dent work opened up the overall wrap of the bell.
The bell, by the way, has a second big patch but also has the feel of being a really nice bell. The horn should produce a nice, classic sound.
Another big problem to fix was the main tuning slide. It was clearly not original to the horn, with a strangely placed water key (as if from an alto or baritone horn). When I got to looking at it I also realized that the slide was of a larger bore than the horn — it was not from any French horn for sure. Just happend to be a bow of the correct width. I found a King bow (from a parts single horn) that would work much better, and used my lathe and parts to make a brace that matched the horn. It’s almost done in the photo below. I used the slide tubes that were with the oddball slide; they are close to matching the horn, but a bit different. My guess is the original main slide went completely missing at some prior point in time.
(In the photo on the right is a device — I’ll come back to that.)
The next big problem to address was the valve section. There was a huge leak at the tube that goes into the 3rd valve from the change valve. I did clean it in the ultrasonic as a preparation for this, it all had to be super clean. But as it was a big job and I had other projects to finish, the horn sat for a good while.
Valve section work
Fast forward to now. To fix this issue I had to tear down the horn further, and then there was a lot of dent work to deal with (but made easier with the horn torn down as it was). I don’t over-repair, but try to get things roughly 90% out on a horn of this vintage.
The photo above shows the soldering underway at the big leak. I think this is the biggest reason the horn didn’t play very well, besides the roached lead pipe. I think the valves are fairly good, I’m hopeful!
The other big thing I pondered and pondered was the valve section bracing. In the first photo there is a “comb” device. That was the bracing in the valve section, probably used as a cost-cutting measure by Conn/Pan American. I wanted a more traditional valve section bracing, and I found parts to make it happen. Oh, and 3 of the valve tubes were loose. In the last photo below, I have things very nearly ready to start putting everything back together. With some luck I’ll have a playable Conn/Pan American Schmidt in a month or so.
At that point I’ll again have big decisions, as it does need a new leadpipe. But I’ll deal with that after the body is together and playable; I do have one I bent for the King Schmidt that will work in a pinch. Working on this horn has been very enjoyable, and I’m hopeful it comes out as being worth all the effort.