A 1/2" CPVC high D would have an I.D. of 0.469", which is an excellent bore size for that key.
1/2" schedule 40 PVC has an I.D. of 0.622", which is best suited for a Bb or low A whistle.
The acetal tubing you’re looking at has a wall thickness of 0.125", which is really too thick.
If you’re interested in an alternative to plastic, aluminum tubing is available in a nice variety of diameters and wall thickness… most whistle makers choose the 0.065" wall thickness variety.
Brass tubing is available in the widest variety of diameters and wall thickness, so you might want to consider it too.
I tried some of this, but with that I.D. the tubing would not fit onto my lathe arbor (0.5") so that I could turn the thick walls down to size. It would have required gundrilling, which is what I normally have to do anyway, so I’ve just stuck with rods. My gundrill makes a bore just the right size.
If you can mount the pre bored stuff on an arbor)make one yourself?), then it would be a good way to start–
I’ll bet they allow a few thousandths of an inch of extra material so that the bore can be machined finished without making it larger than 0.5".
I’ve never tried any prefab acetal tubing, but acetal rod is always a few thousandths of an inch larger in diameter than specified to allow for machining a smooth finish without having to turn it down smaller than its specified O.D.
You can put a glossy smooth finish on acetal, but it’s always a bit rough from the factory.
For sure, Delrin can give you a nice finish that you can’t get with PVC.
My bore on the Pro HiD is .500". We also use this size for the little fifes; in contrast, the piccolo version has a bore of .453", with a significant difference in playing characteristics. That’s about 10% difference in bores, so what I’m saying is that a change of 10% makes a BIG difference in how it plays.
If you’re not set up to cut your own bores from Delrin rod, the standard tubing may give you a disappointing whistle.
I may be slow , but I JUST figgered out that you can get a better finish sanding Delrin by sanding it wet. I just used 400 and 600 grit wet/dry sandpaper with lots of water and got a MUCH better surface than I’d previously gotten using the stuff dry.
I sand it wet, up to 1500 grit, then buff it with a Dremel. It comes out like glass. You have to use very little pressure with the Dremel buffer or it melts a little.
I’ve been using off the shelf PVC ‘plumber’s pipe’ to make flutes (schedule 40, the off-white stuff, 3/4"), and so far I’ve made one ‘G’ and one ‘D’ , and, as far as I’m able to play them, they sound o.k. (I’m a guitar player, remember–been playing woodwinds, oh, a whole week now ). I’ve since run out for a 1/2" length of the stuff, in order to try to make my own whistle.
Are we saying I won’t get a good ‘D’ whistle out of it? If not, is there anything my Dremel and I can do to make it better?
..you know, if I can’t make this work, I can open a pub out of my garage instead…maybe call it “The Hacksaw and Hammer” or more appropriately, “The Bloody Thumb”:lol:
[quote="jsluderBut I like the matte finish on my black Delrin Busman. I don’t think I’d want it any shinier. [/quote]
At 400 or 600 grit it’s still matte, but I’m able to get out some of the concentric toolmarks that I wasn’t able to previously. I’ve thought of getting it shinier, but I’m afraid it’ll show every tiny scratch that way. The matte has a nice grip too.
Yes, and a lot of plastic recorders are ABS. For those, they injection mold the plastic. For my purposes, I’d have to start with a solid rod and then machine the whole thing. It might well be a good alternative to Delrin, which is devilishly hard to glue. I look forward to trying some out on the lathe.
I did some Googling on “abs flute” and came up with the fact that Tony Dixon uses ABS for some of his heads. Not sure if they’re molded or machined.
That depends on the metal. Epoxy works with ABS, so do solvent based glues. Neither one seems to work with brass very well. (forget aluminum) In general, I have not been very satisfied with gluing metal to plastic. There are some acrylic 2 part glues that claim to work. I tried one, but one whiff of that stuff and I felt ill for 3 days. No kidding. That stuff is EVIL. It smells like silicon sealant, only 1000 times more intense. here is a link:http://www.gluguru.com/acrylic.htm
I plan to try ABS at some point. I will prolly start with a piece of bar and go from there. PVC is also relatively cheap and a lot easier to find. AFAIK, K-MAC is the only place to buy ABS on the web.
Where do you buy a gun drill? I usually buy tools from EMCO, but they do not seem to have them. Do your drills have the cooling channel? Can you buy them without it? Also, when you use a gun drill, you need a pilot hole, correct? Does that hole need to extend the length of the finished hole? Or, is it just to start the drill?
I wonder if anyone ever uses shell drills in plastic.
[quote="ctilbury
Where do you buy a gun drill? I usually buy tools from EMCO, but they do not seem to have them. Do your drills have the cooling channel? Can you buy them without it? Also, when you use a gun drill, you need a pilot hole, correct? Does that hole need to extend the length of the finished hole? Or, is it just to start the drill?
I wonder if anyone ever uses shell drills in plastic.[/quote]
I had my gundrill custom made by Danjon in CT. They gave it a specially configured tip for wood, as opposed to metal. It has the air cooling channel, which is terrific-- I hook it up to a cheap compressor and it continuously blows out the sawdust/chips while keeping everything cool. I’d hate to be without it.
The pilot has to be the exact diameter of the gundrill, but only needs to be 1/2" or so deep. The gundrill drills the rest of the hole blind. That pilot hole has to be drilled very carefully and accurately, or the bore will end up offcenter.