Here is an article on the grades of Delrin including food grades. I wonder what grade is being used by the flutemakers who use it.
http://www.dupont.com/products-and-services/plastics-polymers-resins/thermoplastics/Articles/grades-of-delrin.html
I would feel cautious about anything with potentially transportable formaldehydes if one was chemically sensitive, which I am. But then I used a lot of plywood when I built my house in the 90s. Do your due diligence.
I do react badly to perfumes, tobacco smoke, musk, patouli oil, cleaning solvents, soaps, diesel exhaust, pot smoke, etc. I have to be somewhat careful out there. Plastic fumes from the heat generated by machining are really intolerable which is one reason why I won’t ever turn Delrin, and abandoned any idea of using other plastics such as cast acrylic resin. My tools are sharp enough for wood but need to be supersharp to turn Delrin and Acrylic. I’m too lazy and unwilling to keep them that sharp! Otherwise heat is generated and within seconds my workshop smells like the chemical factories of New Jersey back in the 70s (I remember this from hitchhiking from DC to the George Washington Bridge once in 1977).
I use a low viscosity superglue out in the workshop and vent it well when using epoxies (I glue my rings on with this) and occasionally use a polyurethane sealer, again with adequate ventilation. These don’t seem to affect me the way that list of other substances does.
I do turn the occasional ring for bagpipes from the cast GPS polyesters sold as “alternative ivory”. I turned a flute out of it once. One day the middle joint spontaneously broke into two pieces. It was probably just a bad piece. Otherwise its a fairly benign material to work especially if one can keep it cool and vacuum the chips away while machining. Rod Cameron has also made flutes out of it and none of these have spontaneously self destructed. I might have dropped the piece or it could have been cracked in transport. I used to buy it in about 20kg quantities and it was always mailed just wrapped up in paper and tied with string - all the way from Great Britain.
In terms of an end product such as a flute, I would request that it be made in a food grade delrin if possible and that is what the flute makers should be using hopefully. Most likely the chemicals in it are stable in any grade. However, there may be lingering dusts and volatiles resulting from the machining. Thus you might simply want to wash the flute in warm water or wipe it down with a mild solvent such as alcohol before use, so that you don’t ingest any of these dusts as a precaution. With wooden flutes the final step before final assembly is to oil the flute, then wipe off all of the oil which transports any machining dust away, or at least renders them less mobile. Since the Delrin flutes don’t need any oiling or finish, they may still have such particulate. I have seen this in Susato whistles.
I have had to narrow my wood choices down to the ones least toxic to me as well. Blackwood, Boxwood and Mopane are pretty benign. Other rosewoods especially Cocobolo, Bocote, Cocus, and others give me rashes. I can’t use them.
I am not totally anti-plastic. I bought C and D Susato whistles recently. Again, laziness is probably the primary reason why I don’t make flutes from it.
Speaking of plastic flutes, today I am working on a prototype for an Irish Bass Flute in D, one octave below our normal Irish flutes. I am simply testing some concepts and demonstrating the results to Grey Larsen when he comes over tomorrow to have me make a few minor adjustments to the tuning on his alto flute. In the image below, the flute on the top is one of my early D flutes (circa 1986) for scale. Next is the plastic plumbing that will be used as the body of this instrument. Wood will be added for embouchure height, as well as something of a tapered bore to the body. I’ll report back and maybe even have a video of us trying to play this thing (which will require 3 people).
Finally (from the images on the LOC website) a bass flute by Wigley and McGregor circa 1815 at the Dayton Miller Collection, #1239, printed to actual size. The view is about a meter wide and the sounding length of that flute is around 1100mm. I took measurements of this one when I was there recently. Peter Noy sells one very similar based on a flute by Delusse, circa 1750, pitched at A-415, for $4900. I am looking at some of the contrabass flutes and subcontrabass flutes and thinking of the usefulness of a simple system fingered version of these. It could be fun…
http://www.caseyburnsflutes.com/ibs.jpg
Casey
[ Oversized photo changed to link. -Mod ]
It is probably more dangerous in its raw state while being formulated or when heated in manufacturing processes - like turning and boring flute bodies. But in its finished state I have no evidence of it being a hazard. But who knows for sure.