How to make a valve? and a bell?

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Elow
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How to make a valve? and a bell?

Post by Elow » Mon Jun 29, 2020 8:34 pm

Hi, this might not be the right place to put this so move me where you think it should go. A couple years ago i bought a pretty mint condition beuscher mellophone from i think 1907. It was pretty cheap and i really like it, only problem was the first valve. It looked like it had been best to hell and back, literally. It had so many dents in it. I took it to my local repair shop and they gave me two options, to have a third party make a new valve, or a cheaper option that might not work, which it did btw. So i had that all taken care of, but i’m curious as to how someone would make a whole new valve. It’s a piston so i imagine the cylinder could be spun up in a lathe, but then what? I’d really love to know. Also what’s the process of making a bell? Are there specialized people for this, or is it a big shop that would make a custom valve?
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BGuttman
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Re: How to make a valve? and a bell?

Post by BGuttman » Mon Jun 29, 2020 11:00 pm

Making a bell is not for the faint of heart. There is a Mirafone video on YouTube showing how a tuba is made and there are all the steps in bell making. It's a VERY skilled trade.

Look for a trumpet making video on YouTube. I think one of them shows how a valve is made. Its more than spinning one on a lathe.

For 3 valve instruments often the best option is to graft in a new full cluster (all 3 valves with casings). Many makers used to do this. Blessing had a reputation for making valve clusters for other makers.

Just replacing one valve in a cluster can have serious soldering problems.
Bruce Guttman
Merrimack Valley Philharmonic Orchestra
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harrisonreed
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Re: How to make a valve? and a bell?

Post by harrisonreed » Mon Jun 29, 2020 11:41 pm



Step 1: acquire $70,000+ worth of tooling
Step 2: learn how to not cut your hand open while cutting sheet brass with scissors
Step 3: learn how to not burn your house down while torching the seam
Step 4: learn how to safely operate the lathe and not maim yourself while spinning a brass buzzsaw that will become the flare.
Step 5: learn how to not burn yourself while torching the flare.
Step 5.5: practice making bells until they aren't just bell shaped objects. This may involve learning buffing techniques and other treatments that are a huge part of what makes bells respond the way they do.
Step 6: acquire another $50-100k worth of CNC machines.
Step 7: learn CAD
Step 8: learn how to CNC a rotor core
Step 9: ...

You know who knows how to do all these things is Christan Griego. The staff at SE Shires also know how to these things. If you are interested in instrument building, these are the guys to try to work for.
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JohnL
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Re: How to make a valve? and a bell?

Post by JohnL » Tue Jun 30, 2020 8:05 am

Elow wrote:
Mon Jun 29, 2020 8:34 pm
So i had that all taken care of, but i’m curious as to how someone would make a whole new valve.
Here's some basic info from Yamaha:
https://www.yamaha.com/en/musical_instr ... ng002.html
https://www.yamaha.com/en/musical_instr ... ng003.html
There's several more processes involved that they don't get into. The valve guide and valve guide slots. Making the ends of the piston. Fitting everything up. Top and bottom caps for the casing. The spring carrier, if it's a top-sprung valve. Fitting it all together so it works. Plating the piston (not all pistons are plated, but most are).

Repair shops, even big ones, don't usually make valves. It's fairly common for small manufacturers to buy their valve clusters from someone else; as mentioned earlier, E. K. Blessing used to make clusters for a lot of people. Kanstul used to supply valves to several small custom builders, which put them in a bad spot when Kanstul shut down.

If you have an otherwise nice instrument with a munched valve, the normal repair process is to try to find a replacement from a donor instrument (preferably the same make & model). That's why a lot of techs have big boneyeards. If you're lucky, the piston will just drop in and work, but it'll probably need some fitting.
Elow
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Re: How to make a valve? and a bell?

Post by Elow » Tue Jun 30, 2020 8:46 pm

Lots of cool resources here. Thanks!
Amconk
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Re: How to make a valve? and a bell?

Post by Amconk » Wed Jul 01, 2020 3:06 pm

I’m curious how the factories overseas make bells. Do they actually have people on a lathe spinning out a bell? Or are they machine spun? For the thousands of the stencil trombone shaped objects that they turn out, I have to suspect it’s automated.
Michael Conkey
Southern Oregon Trombonist
-Shires Tenor, SS1 bell, TW47 slide, German Brass Seamed tuning slide, standard rotor
-Modified Schiller 7B clone
-King 4B with custom bell
-Yamaha 446G
-Jin Bao Alto
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BGuttman
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Re: How to make a valve? and a bell?

Post by BGuttman » Wed Jul 01, 2020 4:51 pm

The video from Yamaha shows a person spinning the bell.

The video from Rath shows a person spinning the bell'

I haven't seen any videos from Chinese factories.
Bruce Guttman
Merrimack Valley Philharmonic Orchestra
"Almost Professional"
Elow
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Re: How to make a valve? and a bell?

Post by Elow » Wed Jul 01, 2020 7:03 pm

harrisonreed wrote:
Mon Jun 29, 2020 11:41 pm


Step 1: acquire $70,000+ worth of tooling
Step 2: learn how to not cut your hand open while cutting sheet brass with scissors
Step 3: learn how to not burn your house down while torching the seam
Step 4: learn how to safely operate the lathe and not maim yourself while spinning a brass buzzsaw that will become the flare.
Step 5: learn how to not burn yourself while torching the flare.
Step 5.5: practice making bells until they aren't just bell shaped objects. This may involve learning buffing techniques and other treatments that are a huge part of what makes bells respond the way they do.
Step 6: acquire another $50-100k worth of CNC machines.
Step 7: learn CAD
Step 8: learn how to CNC a rotor core
Step 9: ...

You know who knows how to do all these things is Christan Griego. The staff at SE Shires also know how to these things. If you are interested in instrument building, these are the guys to try to work for.
Just watched the video again and something stuck out to me. When i was at an all state convention i talked to a bassoon salesman and tried a bunch of super expensive bocals (the metal tube that connects reed to instrument) and he was talking about the differences of each one and somehow we got into how they were made. He said after the tube is made they melt a pretty soft metal into it so that it doesn’t crack when bent, which is what that video showed but instead to metal it’s ice. I’m sure they both work, but i would assume ice works better. I just thought that was something to point out.
brassmedic
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Re: How to make a valve? and a bell?

Post by brassmedic » Wed Jul 01, 2020 7:34 pm

Amconk wrote:
Wed Jul 01, 2020 3:06 pm
I’m curious how the factories overseas make bells. Do they actually have people on a lathe spinning out a bell? Or are they machine spun? For the thousands of the stencil trombone shaped objects that they turn out, I have to suspect it’s automated.
I've never seen a machine spinning a bell. Maybe it's done, but I haven't heard of it. It takes a pretty sensitive touch to spin a bell correctly. I think labor is pretty cheap in the countries that are making cheap trombones, so it wouldn't be particularly expensive to hand spin them all. I just googled what a machinist makes in India and it said 15000 rupees per month average, which is about $200. I also don't know if stamping a whole bell on a machine is done. I know some factories stamp out the bell stem at least.
Brad Close Brass Instruments - brassmedic.com
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BGuttman
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Re: How to make a valve? and a bell?

Post by BGuttman » Wed Jul 01, 2020 7:59 pm

Elow wrote:
Wed Jul 01, 2020 7:03 pm
...
Just watched the video again and something stuck out to me. When i was at an all state convention i talked to a bassoon salesman and tried a bunch of super expensive bocals (the metal tube that connects reed to instrument) and he was talking about the differences of each one and somehow we got into how they were made. He said after the tube is made they melt a pretty soft metal into it so that it doesn’t crack when bent, which is what that video showed but instead to metal it’s ice. I’m sure they both work, but i would assume ice works better. I just thought that was something to point out.
Before the use of ice or bending metal they used pitch to prevent tubes from collapsing. Mainly because in the era before mechanical refrigeration and before the low melting alloy was invented that was the best available.
Bruce Guttman
Merrimack Valley Philharmonic Orchestra
"Almost Professional"
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paulyg
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Re: How to make a valve? and a bell?

Post by paulyg » Wed Jul 01, 2020 8:45 pm

Your best bet for that mellophone is probably to get a donor valve block (probably any student trumpet will be fine) and just work with the bell you have.

Forget about making a valve from scratch- that's a $500,000 solution to a $100 problem.
Paul Gilles
Aerospace Engineer & Trombone Player
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JohnL
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Re: How to make a valve? and a bell?

Post by JohnL » Wed Jul 01, 2020 9:09 pm

paulyg wrote:
Wed Jul 01, 2020 8:45 pm
Your best bet for that mellophone is probably to get a donor valve block (probably any student trumpet will be fine) and just work with the bell you have.
If you're lucky, you might actually end up with a better set of valves than when it was new. Mellos were generally built to student instrument standards.
Elow wrote:
Wed Jul 01, 2020 7:03 pm
i would assume ice works better.
I don't know if it necessarily works better, but the cleanup is sure a lot easier.
timothy42b
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Re: How to make a valve? and a bell?

Post by timothy42b » Thu Jul 02, 2020 7:06 am

BGuttman wrote:
Mon Jun 29, 2020 11:00 pm

For 3 valve instruments often the best option is to graft in a new full cluster (all 3 valves with casings). Many makers used to do this. Blessing had a reputation for making valve clusters for other makers.
This.

IMO spinning a bell, particularly of that size, is not within amateur abilities or equipment.
Smaller bells are sometimes hand hammered successfully, but now you need to make a solid mandrel, and you'll be repeatedly annealing as brass work hardens.

If I had my heart set on a bell replacement, I would do a wet layup fiberglas bell. You will need a form to lay up on, but it doesn't have to withstand hammering. Auto designers do it with plywood and clay for prototypes. Some time ago I made a trombone bell form with styrofoam and masking tape. That first attempt was not very good, but with some practice and experimentation you could probably make one. If you had access to a lathe you could "turn" one easily out of soft wood or one of the harder waxes.

Then before using fiberglas, do a test run with papier mache. That was where I stopped. I did get a bell but it was frustratingly difficult to cover a flare. It's not a cone that flat pieces can "tile" to. Anyway, I would do a test layup with papier mache then proceed to a fiberglas construction. Caution: auto body repair kits are cheap but they use polyester resin instead of epoxy. That's not as strong and it is more of a health risk because of vapors. If I were ready to make a keeper I'd use one of the epoxy resins like boat builders and gliders use, like a West System.
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