Delrin fipple plug?

GeoMan · Post by **GeoMan** » Mon Apr 05, 2004 12:48 pm

Hi, all. I've been making copper whistles for a little while now, and I'm ready to start experimenting. I've been using plain, unsealed oak for the fipple plugs (didn't bother putting a laquer or anything on them, since I was just trying to get a feel for how to get a good tone out of the mouthpiece -- nothing for serious use). I want something that won't clog easily, not absorb moisture, expand, etc., etc. Lots of whistles use Delrin for plugs and mouthpieces. Can anyone tell me anything about it? For example, how easy Delrin is to cut, sand, work with, how expensive...

I think the sound quality of my whistles is slowly but surely moving up-- as soon as I can make one that sounds that way I'd like it to, I'll post some MP3's, and y'all can set my delusions of grandeur straight.

Cheers,
GeoMan

Tony · Post by **Tony** » Mon Apr 05, 2004 1:34 pm

http://www.smallparts.com/

Tony · Post by **Tony** » Mon Apr 05, 2004 1:36 pm

http://www.smallparts.com/products/desc ... d-zrbd.cfm

Delrin is a brand name. The product is Acetal.

Loren · Post by **Loren** » Mon Apr 05, 2004 3:53 pm

Delrin is pretty easy to work with as long as you don't have to turn it by hand - cutting and sanding is not significantly difficult, but it is best turned on a metal lathe as hand held turning tools will tend to dig in.

Loren

billw · Post by **billw** » Mon Apr 05, 2004 10:51 pm

I use and like Delrin (Acetal) for my new model Village Smithy, as well as almost every other whistle I build now. That said, I still like plain red cedar heartwood for copper whistles. It doesn't swell or hold onto moisture (very little clog potential), and it looks great against the polished copper.

Loren't right on about turning Delrin. Metal lathe, definitely!

The real problem with Delrin has been finding a decent adhesive system for it. So far, best for me has been Apollo 2240 thixotropic gel.

Cheers,
Bill Whedon
Serpent Music

GeoMan · Post by **GeoMan** » Mon Apr 05, 2004 11:21 pm

Hmmm... looking around, I don't see any acetal rods for sale with a diameter that would be of any real use to me without working on it with a lathe (which I don't have access to at the moment). I'll probably look into that cedar heartwood. I've not gotten ahold of any photos of your copper whistles, Bill, but I can imagine what cedar would look like against bright copper.

Thanks, all!

GeoMan

Zubivka · Post by **Zubivka** » Tue Apr 06, 2004 2:34 am

billw wrote:The real problem with Delrin has been finding a decent adhesive system for it.

Why glue when you can pin?

McHaffie · Post by **McHaffie** » Tue Apr 06, 2004 12:33 pm

You should be able to find Delrin in dowel rods at least very close to what you need. look around for it. I'm fortunate enough to have a local plastics and materials company that keeps in stock and can actually fabricate it to whatever specs a customer wants. fortunately I am using a standard fitting size a standard dowel rod happens to work with quite well.

I use a 'dinking' method. that I use a special sharp angled and fluted punch and hammer (dink) into the fitting on each side into the plug on both sides (kind of leaves a pretty star pattern kink in the copper mouthpiece anyway). Once I've crimped and sanded the mouthpiece into shape, that puppy and budging... EVER.

I like this method because there's more surface area being grabbed, and the 'star' that's created from the fluted punch when it rotates and 'bites' into the delrin plug like a drill bit, it helps to keep it from ever rotating. I like this improvement over just using a regular punch which I used to do, and worked just fine, but I think this works even better.

Yet another design idea handed over to the public.

Take care,
John

Daniel_Bingamon · Post by **Daniel_Bingamon** » Tue Apr 06, 2004 3:56 pm

Actually Delrin and Acetal are not exactly the same.

Delrin is a Homopolymer
Acetal is a Copolymer

Acetal is a generic replacement for Delrin, Derlrin is from Dupont and they have a patent on it and it costs a bit more than plain Acetal.
In whistle playing, Delrin and Acetal have almost like properties at repelling moisture. The difference is very small. True Delrin machines better than Acetal does

A belt and disk sander works well with shaping it, as long as you don't let the buildup of matieral on the end of the piece get built up too much.

AngeloMeola · Post by **AngeloMeola** » Tue Apr 06, 2004 6:25 pm

billw wrote: That said, I still like plain red cedar heartwood for copper whistles.

If you use cedar, watch out for Western Red Cedar. It contains a chemical called plicatic acid that can cause severe allergic reactions. Incense Cedar and Cedar of Lebanon don't contain plicatic acid. Neither does the Eastern Red Cedar.

One company I did some safety work for ran short of the incense cedar they normally used and took in a shipment of western red cedar. They had a number of employees have reactions. Fortunately, no one went into shock.

Angelo

GeoMan · Post by **GeoMan** » Tue Apr 06, 2004 11:26 pm

Dangerous and complicated world, this fipple business...

Thanks for the heads up, Angelo.

For the type of copper pipe that I'm using, a 1/2" dowel is rather loose, but a 5/8" is too big. I think a 9/16" dowel would be the perfect size, but I've not been able to find that size dowel in Delrin (or any other material for that matter). With the oak I've been using for my current plugs I've resorted to cutting a length of 5/8" dowling and spending 15 minutes or so whittling it down to the correct diameter(since I don't have access to any other good way of doing the trick, like a lathe). It works quite well, but It's rather tedious.

I just need to find someone who'll sell me 9/16" dowels, or start looking for some pipe that will accept a more standard dowel diameter.

Here's to progress...

Cheers,
GeoMan

brewerpaul · Post by **brewerpaul** » Wed Apr 07, 2004 5:47 am

Do you have a drill press? You could chuck a piece of Delrin in there, spin it, and reduce the diameter with a handheld file. Actually, I do the final fine fitting of my fipples the same way, except chucking them in the lathe chuck. Leave it just a tad too tight, and finish it up with 400 grit wet/dry sandpaper for a smooth fipple surface.

GeoMan · Post by **GeoMan** » Wed Apr 07, 2004 10:46 am

Nope, no drill press... unfortunately, all I have at my command is an assortment of hand/power tools...which usually do the job nicely with some elbow grease and a little patience.

In the end, I'm sure I'll have a Rube Goldberg machine for spinning Delrin taking up the majority of my workspace. Necessity is the mother of invention, after all.

Cheers,
GeoMan

GeoMan · Post by **GeoMan** » Wed Apr 07, 2004 10:52 am

Nope, no drill press... unfortunately, all I have at my command is an assortment of hand/power tools...which usually do the job nicely with some elbow grease and a little patience.

In the end, I'm sure I'll have a Rube Goldberg machine for spinning Delrin taking up the majority of my workspace. Necessity is the mother of invention, after all.

Cheers,
GeoMan

glauber · Post by **glauber** » Wed Apr 07, 2004 11:00 am

GeoMan wrote:In the end, I'm sure I'll have a Rube Goldberg machine for spinning Delrin taking up the majority of my workspace. Necessity is the mother of invention, after all.

It's called a lathe. I hear they're pretty addictive. You'll soon be suffering from LOA.

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