Well, I may be in for it this time…
Just took delivery of a 25lb sack of cement…don’t ask…
(just look up some of those old threads)
cool!!! 
I’m very curious…
–James
Can’t wait to hear it…
Have you built the stand to hold it yet?
You don’t know maybe he is making a concrete Bodhran! 
Ya, dat’s what I know! I know that I don’t know…
Still gonna need a stand. 
Could it be you are going to test the old concrete flute theory… they say it makes no difference what the tootler is made of but my pastry flute sounds awful- tastes delicious though.
Rob
If you are going to make flutes at about 1/3rd lb each you have enough for about 60-70 flutes allowing for wastage.
You could ask Terry McGee to lend you a set of his Pratten reamers to help with the bore.
Ok.
I admit that I might be pouring solidly into this project headfirst, and that the going could easily get rocky, but I really don’t think it will be boring.
It’s still an open question as to weather I’ll be able to stand such a weighty discussion.
Probably just end up in a barrel somewhere as a footnote !
What a punny guy. 
Concrete flutes?!?!?
How…how…Soviet.
Not so viet after avile…48 days to dry completely if you beleif da specs.
You know, this is an interesting project.
I wonder how the concrete’s dimensions will change and how it will affect the flute; also, you have the unique opportunity that woodworkers don’t get: you can start with the bore and then pour the flute around it, rather than having to ream it out.
In a similar vein, I wonder what you’d get if you used a clay-type substance to build a flute around a bore last?
–James
I did pick up a couple of bricks of that stuff…but its still sitting there…its expensive and I’m chicken… 
I read somewhere that flutemakers were making Fajardo wedges out of Portland Cement and a water/glue mixture. The only cement that I could find that came in a small bag was already mixed with sand. The instructions said to use pure Portland cement, the kind that only comes in 100 lb. bags in the stores that I frequent, so that is what I bought. I wasn’t able to lift the 100 lb. bag into the trunk of my car, so I had to split it up in buckets in the store parking lot (I was a Boy Scout, and scouts are supposed to be prepared). The wind was blowing that day, and I remember getting cement all over my clothes. Unfortunately my experiments with cement wedges were a big failure. Of course I didn’t follow the instructions exactly, so my wedges wouldn’t come out of the mould without cracking. I gave up and dumped the whole bag of cement into the trash, which made for one heavy trash container.
Ya…I’m really afraid of that kind of experience…I don’t want to use any fillers at first…in theory, the “perfect” material should behave reasonably enough, but it may be very critical and will certainly take a long time to cure properly…
Anybody else have any “real world” experience with this stuff ???
As an impecunious sculpture student I cast a fair bit of my work in concrete using rubber moulds. It takes a long time to cure and must be kept very wet while it does so. Once your proto flute has set you could immerse it completely for a few weeks at least.
The other thing you will need is some sort of vibrator - such as the edge of an orbital sander to compact it and remove the air.
Again as a student I visited the Portland Cement Association research establishment in Dorset where they had been curing cement blocks for thirty years in tanks and every year they got stronger. Also I was amazed at how they could cast it to a mirrror finish.
The other thing that you need to consider is what aggregate to use, the romans used pumice.
Here’s a link to The Portland Cement Association.
http://www.cement.org/basics/index.asp
If you contacted them I dare say they would advise.
Rob
I’ve had success using loose nylon (santa’s beard chopped up) as an aggregate for small concrete pieces. It doesn’t settle out if you over-vibrate.