TromboneChat

Just an idea came up, is it possible to replace the Hagmann valve rotor with a carbon machined or printed one? Does somebody have an idea or is it just impossible?

Just ask at Lätzsch for proper valves on your Theins

Well, I had once Lätzsch valves on one of my horns. They were very good, but the Hagmann is the better choice for me. I don‘t know if Lätzsch can make Hagmann rotors, but I could ask

The Hagmann valve is made by hard-soldering bent tubes inside the inner casing. I don't see how you could machine that. For printing I don't know, but I would think this would rather tricky.

Why do you want it out of carbon?

LeTromboniste wrote: ↑Thu Jan 12, 2023 8:20 pm

Why do you want it out of carbon?

I can see why you'd want it- the Laetzsch carbon valves are lube-free, super duper light (very little rotating mass to move), durable, and play well. A hagmann style valve would benefit from all of those aspects, since they are so fragile and finicky.

Burgerbob got it. It‘s not necessary to have the rotor in carbon, but it could improve the action of the valve. And that would be cool

The Lätzsch Full Flow valves have been around for at least 10 years, so the tech isn't exactly new. However the core of the René Hagmann valves is definitely more complex than a standard rotary valve, which is what the Lätzsch core is closest to. I don't know if it would be possible to machine the passages. Though, the design would at least give a chance to get a second bearing on the bottom of the Hagmann valve, which would definitely solve some issues.

I phoned today to Lätzsch and as I thought having a carbon fibre Hagmann rotor will be difficult, not impossible, but could be risky. First there would be necessary to find out how to programm a CNC to can make the rotor. But during the machining the carbon material will get warm and expand too much to fit after a Hagmann casing. The risk to get a to big or too small rotor is very high. Plus the costs of all will kill the project right from the start.

However, it would be funny to habe a carbon Hagmann rotor, but I‘m not certain if it makes sense.

I wonder if Hagmann has ever considered making them from heavily anodized machined aluminum, like the Thayer Axial Flow valves were towards the end. That might prove to be a bit lighter than the brass, though the sound would be a bit different.

tbonesullivan wrote: ↑Fri Jan 13, 2023 10:43 am I wonder if Hagmann has ever considered making them from heavily anodized machined aluminum, like the Thayer Axial Flow valves were towards the end. That might prove to be a bit lighter than the brass, though the sound would be a bit different.

The anodized Thayer option is still available. Being made in Minnesota.

dwn8ve wrote: ↑Fri Jan 13, 2023 12:31 pmThe anodized Thayer option is still available. Being made in Minnesota.

I have heard that, but there is not much information out there on the internet about how to get them. I assume they are mostly supplying OEM makers. Are they selling just valves. or the whole kit like OE THayer used to?

tbonesullivan wrote: ↑Fri Jan 13, 2023 12:48 pm

dwn8ve wrote: ↑Fri Jan 13, 2023 12:31 pmThe anodized Thayer option is still available. Being made in Minnesota.

I have heard that, but there is not much information out there on the internet about how to get them. I assume they are mostly supplying OEM makers. Are they selling just valves. or the whole kit like OE THayer used to?

I am trying to help him on an updated website at the moment. It has just been word of mouth and emailing him to get info and start something. He can do either valves alone, or a whole section.

Burgerbob wrote: ↑Thu Jan 12, 2023 8:26 pm

LeTromboniste wrote: ↑Thu Jan 12, 2023 8:20 pm

Why do you want it out of carbon?

I can see why you'd want it- the Laetzsch carbon valves are lube-free, super duper light (very little rotating mass to move), durable, and play well. A hagmann style valve would benefit from all of those aspects, since they are so fragile and finicky.

I'm not convinced that they are finicky because they are heavy; the core is actually pretty light since it is so skeletonized. The difficulty is there's just too much surface area. It does not spin on a bearing alone, as conventional valves do; it is held against the rear flat surface of the casing by a spring, so it is rubbing against that entire surface PLUS the entire inside surface of the oversize diameter of the casing, PLUS the surface of the spindle inside the spindle hole. And then there is a rather thin casing that is completely unsupported on one side. (The valve cap isn't really structural; it functions essentially as a dust cover.) They are prone to warping when installed, and tend to need re-lapping. These things are inherent in the design, and I am skeptical that simply making the core out of a different material would solve all those challenges.

brassmedic wrote: ↑Fri Jan 13, 2023 2:19 pm
I'm not convinced that they are finicky because they are heavy;

I don't think Hagmanns are heavy- something like an axial or Trubore would benefit more from the lightness. But they sure are finicky!

All this discussion makes me happy (relieved?) that I've stuck with mostly standard, robust rotary valves (except for my Conn 88CL which has also been trouble-free). I have no desire to become a rotor mechanic!

Posaunus wrote: ↑Fri Jan 13, 2023 2:37 pm All this discussion makes me happy (relieved?) that I've stuck with mostly standard, robust rotary valves (except for my Conn 88CL which has also been trouble-free). I have no desire to become a rotor mechanic!

Yeah... I feel this. I have a friend who is obsessed with putting Hagmann valves on everything. I dealt with enough issues with my Thayer Valve to never want to really deal with a "finicky" valve again. I don't feel massively restricted by conventional rotors.

Posaunus wrote: ↑Fri Jan 13, 2023 2:37 pm All this discussion makes me happy (relieved?) that I've stuck with mostly standard, robust rotary valves (except for my Conn 88CL which has also been trouble-free). I have no desire to become a rotor mechanic!

FWIW I have played mainly on Hagmanns for something like 20 years. Never had a problem nor do I find them finicky. And they are easy to maintain. Never understood why people had issues with them.

Maybe a Hagmann carbon rotod would make no sense. In this forum the Butler handslide is discussed quite a but and if it really is that the action is slowed down by moisture I guess the Hagmann carbon rotor will not work as hoped. At least in my horns the rotors are all wet and contain a small amount of water. Having a large surface the rotor will be slowed down too much? Maybe.

I don't find hagmanns finicky either, but for some reason that's their reputation. I actually find Thayers to be terrible in comparison.

In terms of maintenance the Hagmann is super easy. Oil it once a week and if you have to clean it, open the cap, open the screw to dissasemble the valve just as much as needed in order to reassemble it afterwards easier. Thayers need much more work.

Thayers are pretty idiot-proof. Easier to take apart than a standard rotor. Just take off the stop arm (normal flat blade screwdriver), unscrew the ring and it's apart. Hagmann valves, on the other hand, are a bit more complicated. You need the correct size allen key to loosen the set screw (and it's a bit challenging to get the key in there with tubing and levers in the way). Then pull off the stop arm (if you disconnect the linkage from the stop arm, remember which way it goes, because sometimes they connect at the inside surface and sometimes at the outside). Don't let the little spring fall on the floor; you'll never find it. Putting it back together, you have to get that little spring in the right position, which is not intuitively obvious. If you don't, the valve won't work. Then index the stop arm correctly on the spindle so the set screw lines up with the flat part. If you don't, the valve won't work. Tighten the set screw, but make sure the stop arm is the correct distance from the valve casing, or the valve won't work. It's not particularly difficult, but definitely requires a higher skill level than a Thayer valve.

What he said!!

And compare all of the above to a rotor that you can oil once a year (if you feel like it) and it will work fine for decades…. That’s how you get the label of ‘finicky’.

Personally, I’m starting to think that all valves that require sealing on two surfaces are more complicated than necessary.

Cheers,
Andy