Thursday, January 19, 2012

More on the bass trumpet

I began soldering the valve slides on to the valve block, but in the process of aligning the third valve slide, part of the tubing split in three spots and broke into pieces... Not too happy now.

There should be enough tubing to rework the slide configuration, but it may point down like a marching trombone or mellophone, unless I can find another main tuning tube.

Then I worked on a customer's 100 year old trombone, rolled out the bell throat (was crushed) and fixed the brace... Only when I was looking at the main tuning slide, did I notice that all of the braces were pitched at an angle - meaning that the customer attempted to pull out the slide, yet since the slide was stuck (a newer slide meant to bring the pitch down to modern 440), he pulled and pulled until he pulled the large end out about an inch and pulling the bell back an inch, everything else stayed where it was. Now I need to lightly and slowly hammer all of the braces back to parallel and lap the main slide to make it a bit more free.

Monday, January 9, 2012

Update on the Bass Trumpet

Found a block of valve casings in the back that are slightly larger than the King 600 - about .470" maybe a little larger. No pistons anywhere though, and I don't feel like digging through a drawer to find them.

Finished the first valve tubing and I'm pretty sure I have the correct length for the second valve. The third slide is giving me issues. I need to find one piece of tubing that is about 6.5" long and .517" OD, essentially the outer slide on the casing side of the main slide in the leadpipe of a King 600 trumpet. I found all the other parts from other King 600 blocks, but one of them didn't have this part. A search through the back came up with nothing, I may have to dig around for some larger tubing - or if I can find all three of those valves....

Then I just need to cut the tuning slide by about 3 inches so that I can remove it. Brace everything after that and then it should be done!

Friday, January 6, 2012

Bass Trumpet / Valve Sackbut

Spent some more time on this project...

The main problem I ran into was figuring out the correct open bugle length and trimming the slides down. It's a lot of work; Back and forth between the grinder, de-burrer, grinder, pipe cutter, grinder de-burrer ... and so on until I had reached a main tuning slide length of about 7 inches on each end. This put me into about a sharp Ab (A flat).

Uploaded from the Photobucket Android App

A little more cutting on some of the straight tubing between the valve section and the leadpipe brought me to a couple inches of Bb. Took some of my left over tubing and spliced it into a section of longer tubing, replacing it, and I came to Bb with the tuning slide pulled out about an inch.

Uploaded from the Photobucket Android App

I was worried that the small bore of the trumpet section would hinder the airflow and somehow make for a stuffy or pinched sound. The way it was setup with the trumpet lengths, yes, it was incredibly stuffy. Found a couple other King 600 blocks with parts of tubing on them and proceeded to measure the ~13" I needed for the first valve slide loop.

Silly me! In the process of soldering the first valve tubing, I placed it on the third valve and convinced myself that I was right. Of course once I tried tuning it to the ~19" that the third valve should be, I discovered my error... so now I had first valve in third valve - in tune, but wrong side of the valve block.

Anyway, had some trouble removing the ferrule on the first valve, so I soldered an inner slide from the second valve and then soldered on the outer slides from the third valve (which came from I think the leadpipe main slide outer slides). Still need to address the total removable slide length, as I have to take off the outer slides from the crook, then solder them to the first valve crook.

As for the second and third valve slides, I might make a double slide for the second valve to keep the side width the same, and leave some room for my hands, and for the third valve I might have a slide within a slide - sort of an extension - as I'm using whatever tubing is available from the parts bin.

With a 12D trombone mouthpiece it sounds a bit like a trombone, but with the Conn mouthpiece that was included with the G/F bugle, it sounds a bit more like trumpet. If I could find an actual bass trumpet mouthpiece, and maybe an actual leadpipe/main-tuning-slide, it might sound better. For my purposes, it should work fine. Still a little wary on valve combinations... If the leadpipe was a little smaller, yet still accepted a larger mouthpiece shank, the tuning and sound might be better off. I considered using a trumpet leadpipe, but wanted a larger mouthpiece - I guess I could always turn down the shank on one of the trombone mouthpiece or maybe cut the leadpipe (!!!!) to the smaller diameter - we'll see how it all works once I've added the bracing and whatnot.

Tuesday, January 3, 2012

Bass Trumpet

(Random picture from 'bass trumpet' search)

Ahh, the bass trumpet... should be a valve trombone, but should be a large trumpet an octave lower than the standard C/Bb trumpet that everyone seems to start out on in grade school. The name sounds cool, just as all bass and contrabass instruments are, yet it seems to be just a valve trombone with smaller bell.

I found a CG Conn bugle in the key of G/F (the main tuning slide allows for enough pull to drop the pitch to F and then be able to tune the bugle in F as well (there's a little line to show where F is)) and while I considered having some sort of contra-alto or contrabass trumpet in G/F, it seemed more appropriate to have it in tenor range like a trombone - lot's of trial and error here, I'll explain:

I took a trombone bell from the scrapheap and burnished all the dents and deformities out as possible, soldered it on to a trumpet tail crook, and then attached it all to a King 600 trumpet block. Strangely enough, this dropped the pitch to Ab from Bb. It worked and had enough pull in the valve slides to play in Ab, but I wasn't real happy learning a new fingering set or transposing. So I went back to the bass bugle (something like 12-13 feet) and cut one of the tubes in half and placed the King 600 valve block into it.... BAD IDEA!

It played awful! The leadpipe and tuning slide made up the first 6 feet or so of .48x" bore then dropped to a .46x" for about 4 inches then back to the .48x". Very stuffy, very unhappy.

Scrounging for a .480" section was impossible, so I decided to cut down the total length. To bring it from G/F to Bb (in the tenor range), I needed to remove 4 or 5 feet - easy enough, it's all cylindrical bore tubing before the bell tail. So removing most of the tubing, without drastically cutting anything as it may not work, I came down to a trumpet pitched in flat C, not Cb (C flat), but a C that was flat. Great! Knowing some C tuba fingerings, Bb had to be first valve.

Not in this case. Since the valve section is still in trumpet Bb, all the tuning slides mean SQUAT. After a bit of playing with different fingerings, I figure out that 1-2 or 3 would give me Bb - granted it was a stuffy Bb because of the small loop of small bore tubing, but I was at least heading in the right direction. The main issue was placing the MAIN tuning slide.

I couldn't place the main slide where a normal trumpet slide is, otherwise it would run into the bell or not have enough pull to tune it in all types of weather. So looking at the parts I had in front of me, I removed the tuning slide from the leadpipe and measure from the tail to the valves. Asking a few trumpet and horn players about tuning helped figure out that about 3-4 inches were needed, just about what I had for clearance in that area.

Not knowing exactly how much I needed for bass Bb, I taped down the third valve and pulled the slide out to where Bb should be. A little tuning hear, a little organ drone there, I came up with about the proper length I needed for the main tuning slide. The original tuning slide was about 13 inches long on each end, so I need to take off about 5 or so inches from each tube, well one side is a little longer than the other to make up for the placement of the valves.

At the moment I have things tacked on just enough for me to play it. It looks like a long trumpet - slightly larger bell and an obviously larger mouthpiece, but to me it sound like a dark trumpet, almost a trombone. The bell is, if my memory serves me, 7 inches maybe 6.5 inches wide. It's like a trombone bell that had the rim cut back, kind of like when people modify modern trombones to resemble the sackbut. The taper of the bell and throat is similar to the sackbut second from the left in this video.

I think that's what I've made - a valve sackbut. Which might be where the bass trumpet really is, somewhere between the trombone and the trumpet, not quite a valve trombone, but not really marching variation of the trombone/baritone.

Here's what I have left:
  • Find longer tuning slides from the scrap trumpets, even if that means putting a slide within a slide
  • Fix the clanking valves that are bottoming out on the casings (regulation)
  • Cut the tuning slide and solder it into place, check tuning and adjust pitch, then repeat this until I find the bass Bb
  • Tape up some braces for placement or tack them on
  • Unsolder everything, clean, buff, then solder it all back together
If given the time and training, I would modify the leadpipe to give me a more even transition into the valve section. Or better yet find a .480" valve block and splice that in. I'm thinking the leadpipe might be the bad bit, it uses a small trombone receiver, so there is a bit of a bore jump. If I could locate the parts for an alto horn or an actual bass trumpet leadpipe, that would be great. For a project though, and something I could maybe play in the community band or at least loan out, it'll have to do. The mouthpiece I'm using is the one that was stuck in the bugle, it works better than my baritone/trombone testing mouthpiece - which is great for those instruments, but give me a bit too much of a trombone sound, when I'm looking for something a little darker yet with that bright trumpet sound.