Overtons do,Hardy’s dont…claims have been made that chamfered holes allow for a more precise seal and others claim the opposite.So, who is right and is this an option when ordering?My personal choice is for non-chamfered holes.Mike 
Just for your information all Kerry Pro’s have chamfered holes and have donefor more than 2 years.
Also they all come tuneable as standard and anodised on request.
Phil.
Phil,I have one of your pre-chamfered low pro F whistles which is my favourite whistle and your low D will be my next.Chamfered or not, yours are the best on the planet although I would still lean towards your older ones if you still have any.Thanks,Mike
So Phil, what is your reasoning behind choosing one over the other?
Erik
Seems not even the Whistle-smiths have an answer to this one…perhaps a mandolin maker would know.
Mike
Sorry guys,was busy editing Jonjo Kellys’ Bodhran solo.
Well in my humble opinion the feel of the chamfer gives the whistle a more organic feel rather like wood and if you own an old Overton which I do the feel after many year is of a chamfered style.Thats why I went for that feel on new whistles,why wait 20 years when you can have that played in feel straight away.Anyone who has played the pipes will know that the chanter has the same yet more chamfer.
Anyway back to editing the next batch of video clips.
All the best guys
Phil.
What’s “chamfer” mean?
Brent
Hi Brent,chamfering is the removal and smoothing of the sharp edges around the parimeter of the holes usually at a 45° angle.What do you think,chamfer or not to chamfer.Mike
Does it change the sound? Does it change anything? Or is it just a opinion thing? That sounded kind of rude…please nobody take it as that way…Bye!
Brent
Chamfering, or “radiusing” if the edge of a hole is rounded rather than bevelled, will affect the flow of fluid – in this case air – through the hole. Because air does flow through the tone holes of a whistle during play, chamfering will improve the efficiency of that flow. There will, therefore, be an interaction between hole diameter, thickness of the whistle body, and whether or not the hole is chamfered, in determining the tone actually produced. We all know that “shading” a hole affects tone, and chamfering should have a similar effect.
For years I played a wooden fife, a Stony Creek Model from Cooperman, that when new had razor-sharp edges on the embouchere and tone holes. I noticed that the fife had good tone, but the “sweet spot” with respect to the embouchere was very small and the fife was therefore difficult to play. After three years things had gotten easier, and I thought I’d just got the knack of it. Then the instrument cracked, and I replaced it with an identical model – complete with sharp edges to the holes – and found myself back at square one. I realized that my habit of rubbing almond oil into the exterior surface of the instrument had over time radiussed the tone holes and the embouchere, and that this had made the instrument easier to play. When I changed to a Model F fife, from Leo Brennan, I found that the maker had already radiussed the holes and that the fife came easy to play.
Offered for what it’s worth.
Thanks Neil,your description and distinction between shamfering and radiusing is extremely enlightening and significant and puts a new light on this subject as the differences between `radiused and non-radiused´holes would be less dramatic as far as sealing the holes go, and unless this topic wanders off topic,puts a nice seal on it. Thanks everyone. Mike:)
Just a thought, but would radiusing a hole underneath or inside the tube make any tonal differences…I’ve read somewhere that wooden flute holes are undercut.Sorry,I think too much. Mike:)
No apologies needed, Mike!
What chamfering and radiusing do is reduce turbulent flow at the entrance to and exit from an opening. Laminar flow, characterized by parallel streamlines, is more efficient and moves more fluid faster, reducing the “friction” between the moving air and the body of the whistle. The airflow in the tone holes of a pennywhistle is both in and out because the air column inside the whistle is vibrating. Treating the inside of a tone hole would have an effect, but would be a bit more difficult for the whistlesmith to accomplish.
The far side of the embouchere of a fife is analogous to the knife in the mouthpiece of a pennywhistle; one’s lips form the windway. Exactly why a slightly rounded “knife” on a fife would play better than a sharp one is not something I understand, but I know it does.
Thanks again Neil,you are a storehouse of usefull information and a treasure to this forum. Cheers, Mike
You’re most welcome, Mike! Glad to help.
Chamfering the inside of the fingerholes can indeed alter tone and possibly pitch. It is also somewhat difficult to do. Best to leave this to the maker, especially if it’s a pricey whistle
I agree with you Paul but it could be a worthy tweak for some lower priced PVC whistles as I doubt this would be an option and I must confess to already doing this last night on my Susato A after reading Neil’s guided tour of the inner workings of his fife and sensed a more pleasing tone afterwards with no change to the intonation.Cheers 
Mike
I tried a PVC Silkstone once which has quite deep chamfers.
I found rapid hole closer more difficult and a tendancy to slur between notes.
I wonder if any one else has noticed this effect.
Joe
i’ve found that the sickle shaped"exacto"knife blade works really well for getting down in there and under cutting a tone hole on wood and plastic pipes and whistles.you can grind down the back side of the blade to 1/2 its thickness to really be able to have the room needed to work in there.i have had success sharpening tone holes using this blade-watch your fingers though,its a scary tool.
Tansy,thats a good tip,thanks.Joe, I havent tried this whistle but seems to me chamfering to enable better slurring at the expense of a good seal is counter productive…a sharp or a very slight radius must make it more playable. Mike