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Re: PAPER HORN "BALMAIN"

Posted: Fri Sep 10, 2021 6:40 am
by IainW
Wonderful to see it all together Alastair. Well done to you and Adrian. Interested to know what sort of weight there is on the needle and is there much difference between the start and finish of a record?
Iain

Re: PAPER HORN "BALMAIN"

Posted: Fri Sep 10, 2021 3:15 pm
by old country chemist
Hello again to you all. Iain-Now this is an interesting one, the weight on the soundbox. This is something that can be critical. To be honest, the horn, with a no 4 soundbox, ( weights 144 grams), gives no weight to a record. I have used a clamp weighing 72 grams, or a piece of lead, weighing 52 grams. I think the 72 gram weight on the soundbox gave a better performance, and I noticed no change in the reproduction throughout, but of course Adrian and I have not tried many records to date. I hope that Roger Mackey will bring some good operatics to the house when he comes to hear the machine in due course. Today, and for the last few days we have been discussing the small problems that I am having with the machine, which I will mention later if they continue. The Watt linkages seem to be doing their job well by guiding the soundbox and the horn in a straight line across the record. I am using a 60 degree needle angle.
I know that a lot of you like as little a weight on the needle as possible, and you are probably right, but I have never really followed that path,and found that the weight can be critical sometimes.
George Overstall once showed me his gramophone playing with a weight of one gram On the bamboo needle point, and he went ahead to play a long playing 33rrpm record quite successfully!-but I never saw him play a 78 that way!
As a footnote: I have weighed every part of this machine (my wife calls it a "contraption!") and the total weight is nearly 30 kilograms.
I also toted up about every costing for the machine, and to date it has come to around £235 I have yet to purchase two strong trestles and a heavy table top to place the machine on. That should be around another £50. I must add that Adrian has only taken a small amount for materials, and has charged nothing for all the many hours of thought and manufacture of the various parts, using his marvellous "Harrison" lathe.

Re: PAPER HORN "BALMAIN"

Posted: Sat Sep 11, 2021 7:04 am
by Inigo
I'm with you, Alastair, regarding the weight on the needle. For steel needles, there is a minimum weight needed for the soundbox to be able to track the groove with no distortion. It is, the needlebar+diaphragm have a certain stiffness that the groove must move through the needle. If the weight is under that minimum, the groove cannot move the needlebar and diaphragm and the needle will skip. Depending on the volume of the music recorded; with soft recordings that limit would be smaller, but with strong passages, or that single strong note seen sometimes, the weight must be greater.
With bamboo needles (I tell about them because are the ones that I know better) there is the added problem of the friction of the bamboo point on the groove. With a much light weight a properly pointed bamboo works well, but in strong passages, it tends to skip. With greater weight it tracks better. And with more weight, the needle point starts to be grinded and burnt by the shellac groove, and this produces two good effects (intuitively and apparently, I have no microscope to actually watch what's happening) that seem to improve the bamboo performance: the needle point starts to be grinded to the shape of the groove, and secondly, and not less important, I've observed on some records and some bamboos that the point gets burnt and seems to be hardened by this effect. When this happens, the bamboo needle can be used several sides without repointing, and works marvelously. I've played as much as ten 12" sides with the same bamboo point with great performance. But this happens only with 'certain' shellac compositions andd 'certain' bamboos.
My source of bamboo is erratic, just pieces or sticks found here and there, so the quality of the needdles I'm using is not sistematically the same. Besides this, I'm using needles mixed from several different sticks. But I've noticed that good hard black bamboo sticks produce needles that work marvelously, and also, the inner parts of certain dry, straight, and hard bamboo sticks, when the fibres are parallel and hard, produce a good sound and last very long without repointing. I'm saying 'inner parts' referring to the parts we usually discard when cutting bamboo needles, because they have no share of the external hard skin of the bamboo. Those inner parts, if have hard straight bamboo fibers, work very well.
Another 'non professional' approach is that I test the bamboo needle by pressing my fingernail against the fibres: if they leave a mark, I discard the needle.
This said, it confirms that there is an optimum weight also for bamboos, maybe a bit higher than for steel needles. At a certain point I made a counterweight and started to use it with several records and types of needles in my 5a soundbox. And finally discovered that with bamboo needles, it was better to use the full soundbox weight (no counterweight), i.e., a hundred plus something grams.
Incidentally, I've found the best needles to be the steel soft size sold by our colleague soundgen, and my own made bamboos of the hardest bamboo parts, both with outer hard skin or without it.

Re: PAPER HORN "BALMAIN"

Posted: Sat Sep 11, 2021 9:33 am
by Ahmed
That's absolutely magnificent! Beautiful result, congratulations!

Look forward to seeing videos of it in action :)

Re: PAPER HORN "BALMAIN"

Posted: Sat Sep 11, 2021 6:06 pm
by Curt A
Alastair,
It's almost a year since you originally posted about this project and now it has come to fruition... Congratulations. I love the design inside your horn and the clever use of the Watts Linkage to accomplish the straight line movement of the horn and reproducer. Your project inspired me to build my Palmodian replica phonograph - thanks for the inspiration.

Curt

Re: PAPER HORN "BALMAIN"

Posted: Mon Sep 13, 2021 1:32 pm
by old country chemist
Thank you all for your kind words regarding the "Neo-Balmain" machine.
As I have to be honest, Adrian Tuddenham with, sometimes an over fertile mind, has come up with something different. When he suggested this type of design I was not quite sure, of it, and I was more interested in another design that he had suggested that was not so unusual, but her managed to persuade me. As I said the other day, there are still a few little bits to sort before we feel it is fit for public consumption!
Some of you are interested in seeing a video of the machine in action. Sorry to say, I would hardly know the front end of a video camera from the rear! Just give me a "Brownie 127" box camera! I will look into getting someone to video the machine when we feel it is running as it should, and will, of course, let you all know.
Until then, it is back to the sorting of different weights for the soundboxes, and a few fiddly items.
Alastair Murray.

Re: PAPER HORN "BALMAIN"

Posted: Mon Sep 13, 2021 1:36 pm
by Inigo
Anyone can assist you recording it with the mobile phone camera. I do my youtube videos with it...

Re: PAPER HORN "BALMAIN"

Posted: Tue Sep 14, 2021 3:22 pm
by old country chemist
Hi All, it seems that Adrian has a camera that will video the machine playing, so may be able in a week or two, to sort that , and then maybe you will hear how good (or not so good) the "Neo-Balmain" is!
Now working on sorting the table for the whole machine to be place upon. 30 kilos will certainly need a sturdy one!
I forgot to mention that when I tried the machine last week, I used 2 or 3 soundboxes. When trying each one, they were connected to the horn with an "Orchorsol" lifebelt which seemed to work quite well. I recently bought a new "Lifebelt" for £15, and the old one that I removed from the "Orchorsol" soundbox was in better condition that I thought, so I decided to use that. I do have a couple of other rubber connectors that I will try as well to see what difference they make to the reproduction.

Re: PAPER HORN "BALMAIN"

Posted: Wed Sep 15, 2021 6:04 am
by jboger
Dear Old Country Chemist:

May I ask a personal question? Are you a Country Chemist who is Old? Or are you a Chemist from the Old Country? Possibly both?

I have not gone through all 20 pages of this thread, but I did read your first post. My grandmother, a Macleod, was born in Manchester and came to the US as a little girl. So being part Scottish I'd like to say we are not cheap but frugal.

By the way, nice looking horn and very interesting project.

Regards,

John

Re: PAPER HORN "BALMAIN"

Posted: Wed Sep 15, 2021 8:20 am
by neilmack
@Gramophoneshane has posted a rather fine picture of a Balmain gramophone on another thread.
Daboll Fog Signal 1 balmain.jpg