Dunhill Red Bark strange filter?

[vlodko]

Recently renewed 1975 Red Bark. Quite an unusual and confusing construction: the tennon looks like made for a filter but the hole diameter is only 5.8 mm (0.23"). Thus both 9 mm and 6 mm filters won't fit there. Does anyone has an idea what it could mean?

 

[owen]

A lovely pipe and my birth year.

 

[jerwynn]

It might be a Great Mystery... but it IS a lovely pipe for sure!

 

[georged]

The hugely funneled tenon found on some Dunhill bents is a mystery that's never been explained. (As far as I know, anyway.)
There's recognizable pattern to it, either. Some just do and others just don't, dating back to the 1920's.

 

[xrundog]

I have a Dunhill and a Parker like that. Here's what I think: The shank is drilled with a slight well. Then the draft hole is far forward in the mortise. Usually one sees that on full bents, but I've seen it in other brands partial bents too. To compensate for the off center draft hole, the tenon is extra wide. Peterson does the same thing. It's also common on old Wellingtons. Another solution some makers use is to make the tenon short. The wider tenon hole smokes drier than the short tenon.

The main problem with the wide tenon, in my opinion, is that the open area collects crud and affects tobacco taste. Keep it clean. Once the wide tenon and or hollow stem gets fouled it can be hard to get it clean and tasting neutral.

It's the main reason I seldom buy old well pipes.

 

[doctorbob]

I'll take a stab at this, I only see the big funnel tenon on bent Dunhill (or associated acts like Parker) is to accommodate the inner tube which is placed in the shank draught, not the stem. The funnel allows the inner tube to extend into the mouth of the tenon off axis from the centerline. On of the patent drawings shows this better than I can explain.
Doc

 

[georged]

There's recognizable pattern to it, either. Some just do and others just don't, dating back to the 1920's.

I just caught this.
It should be, "There's NO recognizable pattern..." of course.
(Ten minute bank-vault edit lockouts are a Crime Against Humanity. Where is the ACLU when you need them?)

 

[vlodko]

The hugely funneled tenon found on some Dunhill bents is a mystery that's never been explained. (As far as I know, anyway.)
There's recognizable pattern to it, either. Some just do and others just don't, dating back to the 1920's.

Thank you for the attention to this topic and for the comments. It would be very boring if everything can be expained

 

[vlodko]

A lovely pipe and my birth year.

You won! I am 3 years elder and my year's pipe looks a bit more straightforward.

 

[vlodko]

I have a Dunhill and a Parker like that. Here's what I think: The shank is drilled with a slight well. Then the draft hole is far forward in the mortise. Usually one sees that on full bents, but I've seen it in other brands partial bents too. To compensate for the off center draft hole, the tenon is extra wide. Peterson does the same thing. It's also common on old Wellingtons. Another solution some makers use is to make the tenon short. The wider tenon hole smokes drier than the short tenon.

Thank you! That sounds reasonable!

 

[vlodko]

I'll take a stab at this, I only see the big funnel tenon on bent Dunhill (or associated acts like Parker) is to accommodate the inner tube which is placed in the shank draught, not the stem. The funnel allows the inner tube to extend into the mouth of the tenon off axis from the centerline. On of the patent drawings shows this better than I can explain.

Thank you, Doc. I'll try to find some more details.

 

[vlodko]

Didn't want you to think people were ignoring you.

Thanks! Even if people can ignore me, they probably won't ignore such keywords as Dunhill
Speaking honestly it was already the late night in Kyiv when I created this topic and and I went to bed almost immediately. Thus I was sleeping while you all were responding to my question. Pardon

 

[doctorbob]

This patent image retrieved from Google shows how a inner tube requires a wide, funneled tenon on a bent pipe to accommodate the off axis misalignment between stem bore and shank draught. The patent shows the inner tube extending past the bend, which can't really happen, but the concept as it relates to the tenon remains the same.

Doc

 

[vlodko]

Doc,
I tip my hat to you! That's exact explanation!
Thank you very much! :clap: :clap: :clap: :clap: :clap:

 

[xrundog]

Ooooooh, now I get it. :idea:

 

[fishnbanjo]

Awesome find! You can still buy the innertube inserts for around $6.95 for a pack of 3 I believe but they only come in one length and it is straight. Don't know if one of the current straight ones would be long enough, or if you could bend one without kinking it, but it would make a great straight shot with a pipe cleaner.

banjo

 

[xrundog]

I tried fitting a standard (readily available) inner tube to the two bent pipes I have with the wide tenons. They do not fit. As banjo suggests, they would need to be bent. And I don't think I could do it without a bender of some sort without kinking them. Too bad as I think I'd enjoy these pipes more with inner tubes. (shrug) Not much to be done besides smoking them as is.

 

[fishnbanjo]

The alternative would be to get some of the automotive tubing sold which is softer and easier to reform but you would need the correct O.D. to fit the I.D. of the hole in the stem, cutting the angle is easy.

banjo

 

[daveinlax]

It's probably drilled for Dunhill's Denicotea crystal filters. 8O

 

[doctorbob]

My inner tube for the 1923 is very short, I have inner tubes still in a 1920's packet for a shape 59. Both styles are different in diameter and length from the current style inner tubes. I don't think you can do an apples to apples.
Doc