Locomotive horn air consumption tests

[@geohig01]

Just starting in Train Horns - thank you for an excellent primer that answered a lot of questions I didn't even know I had! Very nice video.

[@JakeWolf00]

The P5A almost sounds like an RS5T

[@mafarnz]

Interesting, how so?

[@JakeWolf00]

+mafarnz The bells are probably just a little out of tune. Maybe it's just me, but they sound like a Leslie

[@mafarnz]

They are p-laying their advertised notes, C#, E, G, A#, C#.

[@JakeWolf00]

+mafarnz Ok.

[@thelightninghunter23]

Greetings from 6 years into the future. That's actually the same chord as the S5T series.

[@jacobtompke8677]

Can you please do part two with the 3 chime horns you have??? Thnx

[@mafarnz]

I might eventually do that. Generally speaking a three chime will use less air (so longer times) than a 5 chime. (Feel like I have said that before lol). This video took about two weeks of filming and editing to make, so I want to take a break before I do another big video project.

[@flattrain5834]

Do you think you could get 20 sec of honk time with a m3? I might buy one and would like to know how air it takes. Thanks!

[@mafarnz]

The M5 was 12 seconds, and the most air efficient horn the P5 was 25 seconds. An M3 in the same test would probably get about 14-15 seconds.

[@flattrain5834]

Thank you! Sorry for all the questions!

[@mafarnz]

No problem, happy to answer them.

[@campodasvertentesdetectori8635]

Where can I get the pdf diagram of the Wabco E2 horn?

[@terrellshadow2420]

Very nice video matt, good to see somebody schooling the rookies on the air horns basics lol.

[@campodasvertentesdetectori8635]

How many PSI are needed to blow the horn?

[@mafarnz]

Locomotive horns run on 140 PSI, though I run all mine on 120 and they do fine. Go to my channel, I have a few ways to contact me there, I can email you the PDF.

[@midwestmodelrailroadworkshop]

I have a very late 80s K5LA and all the bells except 5 have a bigger inlet hole. With it being as late as it is the 5 is not a big bore. Do you know if it would ruin the tone of the 5 to in large the inlet to match the others or would it just make it louder? I've been wanting to experiment with my spare 90s bells to see if making the inlet as big as 80s ones would work or ruin the tone. Any thoughts would be really appreciated!

[@mafarnz]

Drilling out the inlet will also raise the pitch slightly. What you could do is make a choke just in case enlarging the inlet changes the pitch too much. A 1/4 hex key set screw drilled out the the original inlet size can be installed in the four of the bell. Similar to the chokes used on the large bore 5 bells.

[@midwestmodelrailroadworkshop]

@@mafarnz Good to know! Thank you very much for the information!

[@thegameofhearts]

what diameter airline and valve do you use for your horns?

[@mafarnz]

+thegameofhearts the tank port, hoses valves and fittings are all 1/2".

[@thegameofhearts]

mafarnz I figured. I'm assuming a 3/8 I'D valve wouldn't make all the bells open correctly?

[@mafarnz]

That would work ok for a P horn if it were a short run of air line, but for most horns that won't be sufficient. The fact that the inlet on the horn is 1/2" should be a big clue.

[@thegameofhearts]

mafarnz thanks for the reply. looks like I'm going to have to upgrade my valve before the horns get here

[@RailfanDaniel]

This is what I got from a CFM calculator app I have based on the 20 gallon tank and the air time added in the description. Wabco E2: 29CFM Nathan M5 3/16": 73CFM Leslie S5T: 35CFM Nathan K5LA: 54CFM Nathan P5A: 35CFM A 5/16" M5 is around 90CFM I believe. Just some info for those that want to have an air compressor keep up with their horns. From most videos I've seen, honk time is normally about half of the video. That being said for a 5/16" M5, with 40 gallons of air starting at 175psi (regulated down obviously), a compressor capable of producing 35CFM is needed if two minutes of honk time in a four minute video is required without the air pressure dropping below 120psi. Then again, that's assuming the horn is not being quilled at all, so 30CFM may suffice.

[@mafarnz]

Awesome info, thank you! Is it ok if I add this info to the video description, with credit to you?

[@RailfanDaniel]

Go ahead, no credit needed. I got it all from here, though the app only works for Android unfortunately. play.google.com/store/apps/details?id=cfmcalc.igpf&hl=en I tested my Viloco valve today and it flows about 152CFM at 90psi and 225CFM at 140psi. I can't imagine the Graham White is that much different flow wise, despite what their website says. 70CFM at locomotive reservoir pressures or anything close to that I'm sure is a huge underestimation.

[@HybridBell]

I thought CFM only works if there is an infinite supply of air at the same pressure. e.g 60CFM at 100psi would only be accurate if there was an infinite supply of air at a non-changing pressure of 100psi. Because when air pressure lowers, air consumption lowers. I know for a fact, and according to the manufacturer specifications, at 100psi, a variable orifice Leslie 5T uses approximately 60CFM. Remember, this is only if the air supply is infinite and remains at 100psi the whole way.

[@mafarnz]

True, but it's a good enough approximation.

[@flattrain5834]

Do you guys know how air a m3 needs?

[@andrewwilson5631]

Do you know what notes are played by an M5 or an M3? I got an M3 that was missing the smallest trumpet (so I guess it's an M2) so I am curious.

[@HybridBell]

M5's were designed to play the chord of A 7th Major. An M3 is designed to play A Major Triad. It is very rare to hear an M5 or M3 playing their designated chords, though. The notes played by each M bell are as follows: M - #1: C# (277HZ) M - #2: E (330HZ) M - #3: G (392HZ) M - #4: A (440HZ) M - #5: C# (554HZ) < exactly one octave above the M - #1 bell

[@andrewwilson5631]

Richard Cai Thanks. I figured out that my M2 plays a slightly sharp C and a slightly flat E. That about comes out to a Minor 3rd, so it should sound good!

[@Viloco_Valve_Productions]

Very nice video! My question for you is what is the manufacturer of your horn valve?

[@mafarnz]

I use a Graham white 353 valve, which is an actual locomotive horn valve.

[@jacobtompke8677]

Kk thnx for letting me know!

[@truckstuffmore875]

Nice video ; )