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Hi, Cranberry.
It looks like you have a Waltons (formerly Soodlums) Mellow D there. It’s exactly like my favorite (after tweaking) whistle d’jour. I just recorded a clip on it that will hopefully be of adequate sound quality for Tony to post on Snips 'N Clips.
My Gen Bb is 13 3/4 inches long. I use my right pinky to play the bottom hole. It took some practice, but it’s much easier for me than trying to stretch it with the third finger.
Best wishes,
Jerry
P.S. Is that one on the left the one you started to tweak? It looks like it could use a blade lamination tweak, as we discussed earlier. Some people use guitar picks but others, including me, use soda bottle plastic. I get mine from a two liter bottle because it is less curved and easier to stick to the mouthpiece ramp. I would suggest that you try it. If you can get it to work, you’ll probably be impressed with how good you can get that whistle to sound.
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Not dead, Cranberry.
That whistle’s just the way I would have it before laminating a blade to it. I would recommend that you get some double-faced tape. It’s available at many stores in the office supplies section. It’s also available from hardware stores and home centers for keeping rugs in place. Either kind will work.
I would also recommend that you use soda bottle plastic, primarily because I’ve used it and know it works great, and because it’s readily available.
The important thing is that tiny adjustments to the position of the blade lamination can make a big difference. Take another whistle for an example and estimate where the cutting edge of the blade lamination should end up in the window.
Stick a suitably trimmed piece of soda bottle plastic to the mouthpiece ramp, and look through the mouth end of the windway against a bright background to see where the end of your new blade edge aligns with the height of the windway. It should be about halfway up or a little less, from the floor of the windway.
Make sure the lamination is firmly stuck with the double-faced tape and try out the whistle. Make adjustments to the position of the lamination and to the blade edge until you’re happy with the result.
Hint: moving the blade edge closer to the mouth end tends to strengthen the upper register, while moving the blade edge further away from the mouth end tends to strengthen the lower register. Sharpening the blade edge tends to strengthen the upper register, while dulling the blade edge tends to strengthen the lower register.
After you’re happy with the result, keep it for a day or two and keep playing to make sure you’re still satisfied. When you’re sure, carefully lift the end of the lamination furthest from the window, without releasing the area closest to the window, and put a drop of superglue under the lamination. Press it back down until the superglue sets and try it out. If it hasn’t shifted, you’ll have a permanent lamination. If it’s shifted, you’ll have to pry the lamination off and try again, which isn’t a problem and is just part of the process for some whistles.
Best wishes,
Jerry
Oh, I forgot.
I wasn’t able to play my Gen Bb until I got a thumbrest for it from the Whistle Shoppe. I also have a Susato Dublin low G whistle that I couldn’t play until I got a thumbrest. I play both whistles using the pinky of my right hand, which took some practice to get the hang of, but works fine and is easy enough now.
Best wishes,
Jerry
I just checked the distance on the two Bb whistles I’ve got-
now these are not EXACT measurements- my tape measure is pretty worn-
the Dixon is about 3/4 " between the last two holes
the Generation is 1" between the last two holes
What part of the finger are you using to cover the holes- I’ve got small, narrow fingers but have never had any problem , but as a piper too, I use a piper’s grip on all my whistles.
Cranberry you might try that if you are having trouble with covering the Bb.
The bottom two holes on the small bore Susato Bb are spaced 1-1/16" between the holes (1-3/8" center-to-center).
The Hohner Bb is gorgeous! I don’t think I’ve ever seen a Hohner before.
Thanks for the picture and impressions.
Makes me wonder if Hohner invented this cylindrical metal whistle with head hammered square… what I tend to refer to as “Overton designs”.
Second wonder is who at Hohner’s, or subcontracting for Hohner? They seem to market more than produce many of their instruments, except their harmonicas and squeezeboxes.
Jerry
I’ve got a walton’s Mello D that I tried to salvage after buying it at a garage sale and seem to have screwed up further. I didn’t cut the blade as much as the one Cranberry pictures, but it has a funny echoing or bubbling sound - like I was blowing the through a water pipe - and that peobably makes no sense at all. Funny thing is, the tone isn’t unpleasant except for the effect above and a serious lack of volume. I almost threw it away (I only paid a quarter for it anyway) but I’d hate to do so if it can be salvaged.
Do you think the same fix would work with this one?
I think you should try it.
Now, there’s something I do that’s a little more advanced. Most people don’t do this, and they get good results, but for the sake of completeness, I’ll describe it here.
I bought a triangular file at a hardware store. Then I carefully broke off about a third from the end of the file so that there would be cutting surface right to the end of the file. I use this file to carefully file off some of the surface of the windcutter blade ramp before I do the lamination tweak. This allows the windcutter blade edge to align in the original position where the factory blade edge was. Obviously, the amount to be filed off the windcutter blade ramp needs to be approximately the same as the thickness of the plastic to be laminated. It needs to be done carefully to create a flat surface, using uniform level strokes, without rocking the file.
Best wishes,
Jerry
P.S. Many describe good results without filing down the blade ramp. As I said, this is just how I do it, so I thought I should report on it.
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Cranberry, you don’t have to let go of a whistle to get a sharpened 7th. Here is one possibility: OOOOXX --it shouldn’t affect the note much if at all, and you get to keep a grip in the whistle. And you don’t want to be chomping down on a metal mouthpiece—save your dentist some heartache! 
As you progress, you’ll start discovering a number of such grips depending on where you’re going in a tune. One of the first things I do when I get a new flute is to check out all the possibilities where I can leave fingers down and not affect ( or in some cases, least affect) the note I’m checking out. I think a common term for this is ‘covering’.
Best,
N
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Hi Cranberry,
Are all Bb whistles that far spaced with hole spacing? I’d kind of like to get another one, but if all of them are like that, there’s no hope for me with a low whistle or anything below Bb, which I can barley manage.
I think it’s all a matter of getting your fingers used to stretching like that, kinda like with chords on guitar. I have TINY hands–and I mean tiny.. they’re the size of my 8-year-old cousin’s–and short fingers, and after practicing lots on my Gen Bb, I can handle it fine. I don’t use piper’s grip either. It’s really weird and uncomfortable at first, but you’ll adjust. If I with my abnormally small hands can do it, you can too! 
Good luck!
As for notes being ‘true’ or not, sometimes it depends on the key you’re playing in. Trust your ears, Cranberry. 