I found some diagrams in PDF format:
http://www.public.coe.edu/~jcotting/GP2000.pdf
You could make drone reeds out of the little balsa sticks model makers use. Arundo tongues are out, though; they don’t sell cane in hobby shops, and this project strictly must come from there, right?
Actually hobby shops aren’t necessarily very accesable. Why not outfit your customers from Fred Meyer or hardware stores? Or Home Cheapo?
Lorenzo, no I didn’t know that. This kind of assembly detail is not published anywhere. As I said, I understand the general concept of free reeds as described in the links Tony provided earlier, but I don’t know anything about the hands-on stuff that I would need to know for a DIY project. I’ve been able to pick up little snippets, like how sometimes the end of a free reed is bent to encourage it to sound easier, but the hows and wheres and whys are still unknown to me.
Tony, I am wading through that accoustical study link now, though I think the type of free reed, i.e. idioglottal, discussed in it is too dependent on the associated pipe for its resonance characteristics. I am guessing that the heteroglottal model would be more appropriate, but I’m still reading. Thanks for your help.
What I am thinking of is a). figure out how the damned things work, b). make some, c). do some sampling and sound analysis against a double reed UP reg, d). figure out how to adjust the tone and pitch of a free reed to match the UP double reed reg, e). figure out how to cram the whole thing into a working UP reg package that wouldn’t be too foreign to UPers.
Just one one of those Sunday afternoon projects, eh? 
djm
Now… where were we?
kevin…that was actually my first desire…the hardware store thing, but not one hardware store in my area carried brass tubing small enuff for most of the project. home depot i think had their smallest be 1/2" but that was copper tubing much thicker designed for plumbing.
i do have to get back to the hobby store for longer tubing. i have a working (with resurrected double reeds at the moment) tenor and bari drone. for the bass drone, mathematically, if i keep diameter and reed the same, but double the length it should sound an octave lower. all my drones are tuneable anyway.
anyway…when i go to the hobby store i will look for the balsa. i hadn’t thought of that. i tried making wooden tongues out of wood i had around, but could never get it thin enuff to vibrate with bag air (only mouth blown which i’ve learned has a much higher pressure than bag blown)
i tried a few thicknesses of plastic strips they had, but none were suitable. the balsa thing may be just the ticket, tho.
thanx
If you rule out arundo donax, how about a spruce tongue? I know that works well and I would imagine any wood used in soundboards would work. Just make the growth rings perpendicular to the lay.
Plant, or find, some Elder.
elder makes great drone reeds, especially in flat pitch sets. I first came across them in the museum in keighley in a coyne set. dont know how old they were but they looked ancient. After seeing these i tried some in my B set and the difference was amazing once i got the knack of making them
They have quite a beautiful sound in drones, and personally I enjoy them as chanter reeds. They’re generally a little softer than cane in a chanter and one Irish player I talked with asked me “now why would you do a thing like that” when I mentioned using Elder for a chanter reed. He’s a session player and said you likely wouldn’t be heard in a session. Depends on the session & reed, of course.
Anyhow. Elder’s wonderful for drones and certainly worth trying in your chanter. Remember that the berries are mild to dangerously poisonous. Which makes me wonder why the local grade school recently planted a large plant on their property.
Dionys
i’ve wanted to try elder for my good chanter. Where can i get some short of a nature walk?
won’t work for the brass project, tho…too specialized to work and too tuff to find.
Are elderberries poisonous?
Unripe elderberries contain cyanide and can cause severe diarrhea. The concentration is in the seeds rather than the fruit flesh. So, elderberries should probably never be eaten raw. The unripe black elderberry and the seeds contain the toxin hydrocyanic acid which is destroyed by cooking. Black elderberries are the only ones used for human consumption. Red elderberry (S. pubens) is considered poisonous and should not be used since cooking does not destroy enough of the toxin.