Hi
just for the fun of it (and my ignorance of the physics) what would be the argument against shortening the foot slightly to temper a bit of ‘flat footedness’? Did I perhaps remember Jon saying he’d done this?
PS. should have checked the archive first, as there are a few relevant comments
https://forums.chiffandfipple.com/t/new-flutes-old-flutes/62693/32
https://forums.chiffandfipple.com/t/polish-flute-renovations/66779/2
https://forums.chiffandfipple.com/t/historical-flute-syndromes/55655/14
Hey,
Since the New Year’s Eve I have become the proud owner of a beautiful Thibouville flute, of which I will report in more thorough detail later.
One of the first things that occured to me, was that the F sharp was very flat – indeed almost back down to F. My first reaction was to find someone with a dremel 
But then I realized that I would be the first one since 1870 to think this was necessary – this didn’t sound realistic to me, too.
A little research later I found out that the F# is flattened in order to obtain an acceptable F through xxx xox . This actually makes a lot of sense on the instrument. Likewise, as Terry McGee suggests on his webpage on the topic, the flat foot was there for a similar reason, although it is not further specified. But since Terry wrote comments are welcome, and you’re asking, here goes:
It is my personal guess that the flat foot was introduced for exactly this same reason as the flat F#: the fingering of xxx xox . Without any kind of compromise, this fingering would always remain sharp because the tone is so close to the end of the instrument. On more “modern” large holed instruments the effect would be annulled due to the large F# hole pulling the tone upwards, but on a French instrument (and AFAIK also on a Baroque) this hole is almost as small as the other holes.
I can attest that I already employed the cross fingering mentioned above with good results; if your only alternative is a short F key, it is a very useful fingering indeed. Concerning the F#, I can easily “lip” this tone back up.
So coming back to your original question: myself, I wouldn’t dare to drill into this beautiful and well-thought through instrument from 1870. Would you? 
no, I think it’s unlikely that I’d get out the hacksaw simply for the sake of experiment 
.
Then again, I am interested in best solutions for ITM playing. I was looking at modern makers who base their designs on old Rudall measurements and I wasn’t sure who kept to the flat foot (and key venting) measurements and who made deliberate adjustments. e.g. reading various websites, some like Geert (Lejeune) make it clear that the model does replicate the R&R, including flat foot etc, but others like Terry (Mcgee) emphasise re-engineering for 440 tuning and ‘whistle’ fingering, so I was wondering about others like Michael (Grinter) and Chris (Wilkes) - I’d be interested to know which makers scale their R&R copies ‘old’ style or ITM style.
PS. contradicting myself there a bit as Irish trad style might imply the sound of old flute scaling, but you know what I mean
Just don’t shorten the foot from the nether end if there are eight keys! Ditto for a vented, long foot. This, among other conceptual breakdowns, is what got the former owner of my dear, mistreated old Wylde into trouble; when I got it, it had two C# keys on the foot, thanks to the backroom circumcision.
Rob
Oy vay 
And without even a Moyle 
Bob
In that case I think it is worth to question wether the abovementioned fingering would work at all on a large holed instrument. It is my guess it doesn’t (see also the R&R M&E fingering chart), but maybe someone else can confirm this. If it doesn’t, or you don’t plan to use natural f cross fingering anyway (not in Irish trad I guess, but again, please confirm), then I see no reason for having a flat foot myself (apart from the obvious having your feet run over by a truck, of course).
I have DREMELed two antique flutes with excellent results. also one of them had the foot shortened with, again, sucess.
and a third one will go the same routine. 
I like 440 and whistle fingering. I’m not a yougster to learn new tricks.
Getting the flute up into the air column, particularly the close edge, may reveal that the foot isn’t as flat as you think. It always does for me + produces a clearer more focused tone.
Regards
H
Well, right, I suspect that’s what was taught to people back in the day: you would simply change your embouchure towards the lowest notes. Once it’s a habit it works like a charm, and the alternative fingerings still work as well.
That also seems the reason to me why the foot was still flat on lower instruments: people were still taught the habit, so they would feel that large holed flutes were out of tune if they didn’t have a flat foot! Then it gradually disappeared as soon as everyone got used to it.
@BullFighter: whatever works. A lot of antique flutes will probably come to you in such a state that most people would just use it as firewood, in which case restoring and re-drilling it is a very graceful thing to do 
Mine came to me in such an appreciable state, that it would seem like a sin; also, I have good use for its fine ability to play in different keys.
My limited experience leads me towards the same observation, a tight covered embouchure, keeping the flute up, paying attention, listening, playing in front of the mirror. Works well on a D arpeggio type tune, but I still have difficulty moving between the (b)D and the (#)E or playing a more E/A based tune. I can drop the Es and As a bit but then the F#, D, C start to sound really flat in the context of the tune. Practice, practice.