What kind of aluminum would you use?

I came across a very nice wind chime recently. It was quite large and had a real nice sound. It looked to be made from aluminum tubes 2" in diameter with a 1/8" wall thickness. The tubes varied in length from about 4 feet to about 3 feet (6 in all).

The item was priced at $499. I figured I could make one for about $150, so I ordered a 4 foot sample tube made out of 6061 aluminum.

After suspending it on a wire, I gave it a try with a rawhide mallet. It sounded bad. The harmonics were clashing with each other.

Does tuning it simply involve machinging a little off the length or did I buy the wrong kind of aluminum?

Gary

Reply to
grice
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What grade of 6061 did you get?

The location of the support is extremely critical, get it wrong and you will supress some of the harmonics. Cutting length off will tune it up, but also move the critical suspension point.

Do a google search > I came across a very nice wind chime recently. It was quite large and

Reply to
RoyJ

Varying the length will vary its ferquency. Longer is lower. A better sound would come from a harder aluminum, and I'd be tempted to try 2011T3 or T8. I don't know if it's available in tube, but it could be bored. A thinner wall will give a much more pleasing sound, too: less thunky, more melodic, more sustain.

Dan

Reply to
Dan_Thomas_nospam

We have a short (aka normal size) and a long - deep tone wonderful one. It didn't cost us $500 by any means...

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

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Dan_Thomas snipped-for-privacy@yahoo.com wrote:

Reply to
Martin H. Eastburn

Another option; old scuba tanks. I've seen them in some stores, suitably disguised with fake verdegris paint jobs. Old tanks than won't pass hydro can be had for scrap. Then just cut off the bottoms and hang from the tank valve threads. I think the tanks I saw were aluminum 80's but they could have been steel.

Reply to
oldjag

The tube is marked as follows: ASTM B429 6061-T6

Does that tell you what the grade is?

Great tip! I found way more information than I need. Thanks.

Gary

Reply to
grice

You want 1" tubing. If you go larger - the formula change due to the volume...

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

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oldjag wrote:

Reply to
Martin H. Eastburn

Borrow an electronic digital instrument tuning device (commonly used with guitars). Tap the suspended tube and see if the tube is 'in tune'. If not, shorten until it is. Same with the others. Pick a group of the ones that sound best together (a friendly musician may help you with this -- I had my brother help me out here). You may have to shorten some to the next higher band range (sorry, I don't know the musical terms here). I did the same thing years ago using copper pipe.... still sounds beautiful, and the slightly weathered surface corrosion looks good too. Larger diameter pipe had the same sound but was just louder.

Reply to
Al MacDonald

According to Al MacDonald :

You do need to pick a note for the first tube and adjust the others to be in harmony with that first one. These are ratios of length which result in ratios of pitches.

It really does not matter whether it is truly a standard note to start with -- as long as the rest are in tune with *that* note. Most people don't have absolute pitch, so simply a nicely tuned ratio from whatever starting point will sound good. Probably a selection of a third and a fifth from the starting note (e.g. from 'C' as the starting note, an 'E' and a 'G' will produce a nice sounding major chord. For the same diameter, the lengths will probably be in ratios of 1.33:1 and

1.5:1 (if I have not messed up my calculations).
[ ... ]

This is a single tube? Probably your problems are from the harmonics from your choice of where to suspend it. Try holding the tube between thumb and index finger, and bashing the middle of the length, then sliding your fingers down a little way and trying again. Keep this up until you find the position with the minimum vibration felt in the fingers, and the clearest tone. Then drill the holes for your support wire through there. Attach the wire to two places separated enough so that the wires leave it at an angle (perhaps 30 degrees or more) so the wire won't touch areas other than where it passes through the tube.

This means that when you are tuning a second tube, you will need to remove from both above and below the support point, to keep that sweet spot for the support.

Tuning does involve changing the length (both above and below the sweet spot), but first you need to get a pure tone with no awkward harmonics by finding the sweet spot to support it.

Good Luck, DoN.

Reply to
DoN. Nichols

And with that particular tuning selection, you can be assured that you can talk your local NBC Affiliate station into doing a public interest story on homemade wind chimes.

Just grab a leather mallet and tap G - E - C in that order. ;-)

If I have to tell you who owns NBC...

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Reply to
Bruce L. Bergman

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