I finally managed to collect enough old welding bottles to make a wind chime . Oddly one does not seem to have a good tone , so I will run one short until I find another bottle . I need some help as to the tube lengths . Has anyone got the lengths for 9 " bottles ? Or how to determine alternate lengths as I have a limited max length . Ken Cutt
Ken: I am not sure I understand the question. Do you mean what length gives the best tone(s)? I recently did a garden bell using a large oxy tank. It seems the longer the tank the deeper the sound. How are you suspending them? Try insulating the suspension with a rubber washer or gasket. It may be your suspension comprimises the vibration. Good luck.
Take a short chunk of ALM. pipe and hold it between your finger and thumb... Tap it with a screwdriver and move your hold lower on the pipe ... You will find a happy spot that make the pipe really ring... Thats where you need to drill the holding screws for mounting... Somehow you need to do this with your tanks to find the happy spot...
I am looking to find out what the different lengths should be in relation to each other . The sound of all but one is great , just the same . Now I need to get them to sound different from each other . So far all I have done it cut off the top and bottom . I would like to get the various lengths close on the first cut and then tweak if needed . The sustain on them is extremely long . Well all except one , I have no clue why it sounds flat . It is the tube itself . Suspension will be an internal bar with the ends tapped . An eye bolt in the middle to hang them and 3/8s bolts going through 1/2 holes in the tank walls . It all hanging from a square tube frame . I have not cut the frame sections yet though so I am open to any suggestions . Just that I have the square tubing in my scrap pile so figured to use it . Ken Cutt
Thanks for the site I have it bookmarked . This is looking a lot more technical then I first thought . I think time to get help from the kids to plug numbers into the formula . Ken Cutt
Thanks for this site also . I bookmarked it as well . The calculator is great only it tells me I would need a welding bottle 169 inches long . all the equations are a bit intimidating so I will have to get one of my kids to help me plug in the numbers . Hopefully I can get to the actual cutting this weekend . Great site well very helpful . Ken Cutt
I will get some pics for the dropbox as soon as I get a little further along . With luck this weekend . I am surprised as to the tone of these bottles . It is very bell like and a much higher octave then I was expecting . The sustain is amazing and I think it will even improve once I get rid of the 1/8 inch or so of paint on the outside . The insides have a black coating(some sort or rustproofing I expect) . There are a few rust pits inside of some and none at all in the others . Really a surprise to see so little rust as some bottles first date stamps are mid
60's . Which should mean they were produced in the 50's . Charlie emailed me to suggest that the one that will not ring may have a crack in it . I think once I investigate He will be proven correct . Ken Cutt
I know that tubular wind chimes use a suspension point at the sound "node", where the waves cancel out (22.4% of length from the end). If you are using a closed tube, if might be different, but once found this will permit you to use a solid mounting that does not dampen the wave.
As far as *one* sounding flat - it may have a flaw in it. Possibly a crack. Like ringing grinding wheels.... No ring = don't use. I think it may have been Ted Edwards posting a long time ago with some kind of dimensions for wind chime tubing - formulas for different notes, or
1/2 steps or something. Possibly google the newsgroup for windchimes. HTH. Ken.
I have read that if you set the tube horizontal and put some fine sawdust on it that the nodes will be apparent if you whack the tube a few times.
You are correct about Ted's post and some people don't clean out the in box very often. Havn't seen any posts from Ted for awhile.
Here is Ted's post on May 4, 2001
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I made a wind chime for my wife Christmas '99. The material was polished rigid 1/2" copper type L water pipe. I chose this material because it has a nice tone, it looks nice, is inexpensive and readily available. Harder metals give a harsher tone.
I've seen 22.5% and 22.42% of the length quoted as the correct suspension point. An interesting coincidence(?) is the fact that a uniformly loaded beam supported at points 22.315% from the ends will have the same deflection at the middle as at the ends. Whether this is more than coincidence, I have not investigated.
A pentatonic minor scale has the property that all combinations of notes are harmonious. One example of a pentatonic minor scale is the scale you get if you play only the black keys of the piano. Much Celtic music uses this scale. This is the reason that the drones of the bagpipes do not give a dischord with the notes of the chanter. This phenomenum, and its pleasant sound, also makes this an excellent choice for a set of windchimes. Let the wind blow and multiple notes ring out! You will get pleasant chords.
I have found three interesting references on the web at
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The first of these gives a formula for the frequency of a chime. Using this formula and sound velocity data from the Hanbook of Chemistry and Physics, I combined this with my own software for moments of inertia, etc. to come up with a function to find the lengths of the tubes and the suspension points.
Below is a table for two octaves of a pentatonic minor in D using the above mentioned copper pipe. The chime set I made for my wife uses six tubes tuned to the lower of the two octaves shown.
Length 19.261 18.18 16.671 15.735 14.852 13.619 in 489.22 461.77 423.44 399.68 377.24 345.93 mm
Support 4.318 4.076 3.738 3.528 3.33 3.053 in 109.68 103.53 94.94 89.61 84.58 77.56 mm
Length 13.619 12.855 11.788 11.127 10.502 9.63 in 345.93 326.52 299.42 282.61 266.75 244.61 mm
Support 3.053 2.882 2.643 2.495 2.355 2.159 in 77.56 73.21 67.13 63.36 59.81 54.84 mm
The relative frequencies are fine - no dischords. One of these days, I might just hook up a microphone and a scope and see how close the frequencies are in absolute terms.
ACK! Who SAYS pipes don't give dischordant sounds? "Pleasant sound..."?
ACK! My son is a piper; both Highland and Illean.
"Pipes are an ill wind that no one blows good." "Squeezin' cats to death again, are ye?" "Still wearin' that bag o' rot & phlegm?" "Repairing the tone of Highland pipes is simple; first, build a small bonfire...." "They're called 'The Ladies from Hell'".
A 'famous' Physics experiment is detailed here - just what you need. Keep the mind clean and pure - it is a 18,19 year old topic in school - I had it at 17. (when I couldn't spell all that well :-) )
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Waves - Kundt's Tube
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member
These are more like a traditional bell, with suspension at the neck. I think that *any* support point other than where the valve once screwed in will result in damping of at least some modes, and serious modification of the sound.
As for the lengths and the formulas telling him that he needs a longer cylinder than is physically possible -- I think that he needs to simply measure the pitch of the longest practical one, perhaps remove a bit of metal to tune it to a known standard pitch (if it is important that it play in tune with other instruments), and then shorten the remaining ones to produce a scale based on the longest (and thus lowest-pitched) one as a starting point.
I'm not sure that the formulas for normal wind chimes would be very useful with bells made from welding tanks anyway -- unless the top curve were cut off as well to make them into true cylinders. And typically, you need several diameters of cylinders to make good-sounding wind chimes over a full octave scale range -- which means several sizes of welding tanks -- perhaps down to the "MC" size.
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